1

July 2001

100MDHSMethods for the Determination of

Hazardous SubstancesHealth and Safety Laboratory

Surveying, sampling

and assessment of

asbestos-containing

materials

CONTENTS

Introduction 2

Overview of requirements for surveying andsampling 3

Aim, purpose and type of survey 3

Survey planning 5

Health and safety risks 7

Surveying 7

Bulk sampling strategy 9

Bulk sampling procedures 15

Assessment 17

Documentation 19

Quality assurance procedures 20

References 20

Acknowledgements 21

Annex 1: What ACMs look like and where to findthem 24

Annex 2: Example of a survey and samplingequipment checklist 43

Annex 3: Asbestos warning label 44

INTRODUCTION

1 This MDHS sets out how to survey workplacepremises for asbestos-containing materials (ACMs)and how to record the results in a usable form. Italso gives advice on how to recognise and samplesuspected ACMs. The MDHS has been produced aspart of guidance issued by the Health and SafetyExecutive for people carrying out surveys. It will alsobe of interest to those who commission surveys.

Regulations

2 The Health and Safety at Work etc Act 19741

requires an employer to provide a safe workplace.Work with asbestos is covered by its own set ofregulations – the Control of Asbestos at WorkRegulations (CAWR).2 There are duties to prepare arisk assessment and to make written arrangementsto protect those at risk in the Management of Healthand Safety at Work Regulations 1999,3 and tomaintain workplace buildings/premises to protectoccupants and workers under the Workplace(Health, Safety and Welfare) Regulations 1992.4

Arrangements to deal with asbestos duringrefurbishment may also be required by theConstruction (Design and Management) Regulations1994.5 It is intended that CAWR6 be amended byintroducing a specific duty to manage the risk fromasbestos-containing materials in premises. Thisspecific duty will be supported by an approved codeof practice (ACOP) and associated guidance.

Managing asbestos

3 The new regulation will create an explicit duty toassess and manage the risks from asbestos inpremises. The risks will vary with circumstances,ranging from normal occupation of a building to therepair, refurbishment and demolition of thepremises, and they will each need to be assessed.This assessment will be used to produce amanagement plan which details and records theactions to be undertaken to manage and reduce therisks from asbestos. The broad requirements onemployers are to:

■ take reasonable steps to determine the locationof materials likely to contain asbestos;

■ presume materials to contain asbestos, unlessthere are good reasons not to do so;

■ make and maintain a written record of thelocation of the asbestos and presumedasbestos materials;

■ monitor the condition of asbestos andpresumed asbestos materials;

■ assess the risk of exposure from the asbestosand presumed asbestos materials anddocument the actions necessary to manage therisk; and

■ take steps to see that the actions above arecarried out.

To manage the risk from asbestos-containingmaterials you will need to:

■ keep and maintain an up-to-date record of thelocation, condition, maintenance and removal ofall asbestos-containing materials on thepremises;

■ repair, seal or remove, if there is a risk ofexposure due to its condition or location;

■ maintain it in a good state of repair andregularly monitor the condition;

■ inform anyone who is likely to disturb it aboutthe location and condition of the material;

■ have arrangements and procedures in place, sothat work which may disturb the materialscomplies with CAWR; and

■ review the plan at regular intervals and makechanges to the plan and arrangements ifcircumstances change.

Health and safety issues

4 Surveying and sampling ACMs can give rise toexposure to asbestos and is covered by CAWR,which require an assessment and plan of work to bemade, setting out the control measures andpersonal protective equipment (PPE) to be used. Italso requires that adequate information, training andrefresher training have been given to the samplingpersonnel. Sampling ACMs is, however, exemptfrom the Asbestos (Licensing) Regulations (1983) asamended,7 but is covered by the CAWR ACOP onunlicensed work.8 As other hazards may be present,such as working at heights and electrical hazards, arisk assessment will need to be carried out beforecommencing work on site (see paragraph 25). Itshould include any safety aspects and record anysafety protocol to be observed on site. Firealarm/evacuation procedures should be included.

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OVERVIEW OF REQUIREMENTS FORSURVEYING AND SAMPLING

5 Anyone undertaking surveys or samplingshould:

■ have appropriate training and experience;

■ be able to demonstrate independence,impartiality and integrity; and

■ have an adequate quality assurance procedure(see paragraphs 67-69).

Appropriate training, for example, is provided bycourses organised through the British Institute ofOccupational Hygiene (BIOH) (see paragraph 67 forcontact information).

Asbestos management programmes

6 In order to have an effective asbestosmanagement programme, it is necessary toestablish clear lines of responsibility for theprogramme’s management and implementation. Asurvey of the premises must be undertaken to locateand assess the ACMs. The results of the surveymust be recorded in an easily retrievable form,which can then be used to make a risk assessmentand draw up a management plan. The managementplan may include some or all of the followingoptions:

■ clean up debris;

■ repair;

■ encapsulate (paint or seal);

■ enclose;

■ remove;

■ maintain and update log of ACMs;

■ monitor condition (applies to all presumed oridentified ACMs);

■ restrict access/isolate;

■ label or colour code;

■ inform;

■ train;

■ define and use safe systems of work;

■ operate a permit-to-work system.

Several of the management options apply to allACMs and are required by CAWR. Others areappropriate for ACMs which have a high material orrisk assessment score. Guidance on riskassessment and the management of asbestos willbe available from HSE. Advice from the Departmentof the Environment, Transport and the Regions(DETR) is also available.9

Asbestos surveys

7 An asbestos survey has three main elements:

■ firstly, it must as far as reasonably practicablelocate and record the location, extent andproduct type of any presumed or known ACMs;

■ secondly, it must inspect and recordinformation on the accessibility, condition andsurface treatment of any presumed or knownACMs;

■ thirdly, it should determine and record theasbestos type, either by collectingrepresentative samples of suspect materials forlaboratory identification, or by making apresumption based on the product type and itsappearance etc.

This information must be held in a suitable(upgradable) form and should be accessible to andunderstandable by all relevant personnel.

Material assessment

8 The purpose of the material assessment is toestablish the relative ability of various types ofACMs to release fibres into the air, should they bedisturbed. The type of fibre is also taken intoaccount. This assessment can be carried out as anintegral part of the survey, as it requires noknowledge about the building use etc. A simple fourparameter additive algorithm is used to assess thelikely magnitude of release from the material, givena standard disturbance. This is evaluated using fourcategories: high, medium, low and very low.

AIM, PURPOSE AND TYPE OF SURVEY

Aim and purpose

9 The type of survey undertaken may vary,depending on the aim and purpose for which it is tobe used. Surveys before demolition andrefurbishment will continue to be required underCAWR and the CDM regulations.5 However, it isanticipated that most surveys will be undertakeninitially to comply with the duty to manage asbestos

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in premises. In these cases, the aim of an asbestossurvey is, as far as reasonably practicable, to locateand assess all the ACMs present in the building andits purpose is to present the information collected ina way which allows the employer to manage therisk. In situations where a surveyor is used, the aim,purpose, type of survey and report format requiredshould be clearly established in the original invitationto tender, or agreed with the client at a preliminarymeeting or site visit before starting the survey. Oneof the main issues is to decide when samples shouldbe taken to prove that ACMs are not present.

Presumption or identification of ACMs

10 An experienced, well-trained surveyor, familiarwith the range of asbestos products, can usually, byinspection alone, say that a material can be‘presumed’ to contain asbestos. This presumptioncan only be tested by laboratory analysis ofrepresentative samples of the material. A low-magnification stereo microscope examination of thesample followed by polarised light microscopy (PLM)of selected fibres, as outlined in MDHS 77,10 is themost widely used and cost-effective method incurrent use. In the absence of analytical evidence,many non-asbestos materials will also be presumedto contain asbestos, unless there is other strongevidence to support a reasoned argument that theyare highly unlikely to contain asbestos.

11 This therefore creates two levels ofpresumption: one where there is a 'strongpresumption' that the material does containasbestos but a laboratory identification has not beenundertaken to confirm this; and a default situationwhere it must be 'presumed' to contain asbestosbecause there is insufficient evidence to suggestthat it is not an ACM. An example of a 'strongpresumption' would be thermal insulation on a pipewhere fibres are clearly visible and have theappearance of asbestos but no sample analysis hasbeen undertaken. Where similar construction existsand laboratory analysis of one of the materials hasconfirmed the presence of asbestos, there is astrong presumption that the other similar materialsalso contain asbestos. Materials where no asbestosfibres are visible but asbestos is known to havebeen commonly used in the manufactured productat the time of installation (eg floor tiles, ceiling tilesand insulating boards) will be presumed to containasbestos. A reasoned argument to suggest that amaterial does not contain asbestos would be:

■ non-asbestos substitute materials werespecified in the original architect's/quantitysurveyor’s plans or in subsequentrefurbishments;

■ the product was very unlikely to containasbestos or have asbestos added (egwallpaper, plasterboard etc);

■ post-1985 construction (for amphiboleasbestos-containing materials such as asbestosinsulation board, see Table 1);

■ post-1999 construction (some chrysotileproducts were prohibited in 1993 and nearly allwere prohibited in 1999).

12 The conclusion that ACMs are not presentcannot always be easily reached. The regulationsrequire that reasonable steps are taken. It may insome circumstances not be reasonable to decidewholly on age and/or original specifications, whichmay have been circumvented during theconstruction of the building. There are alsoexamples of poor removal practice leavingasbestos-containing debris and residues, and areaswhere asbestos has been removed previously willneed to be inspected.

Type of survey

There are three types of survey referred to in thisMDHS.

Type 1: Location and assessment survey(presumptive survey)

13 The purpose of the survey is to locate, as far asreasonably practicable, the presence and extent ofany suspect ACMs in the building and assess theircondition. This survey essentially defers the need tosample and analyse for asbestos (or the absencethereof) until a later time (eg prior to demolition ormajor refurbishment). The duty holder bearspotential additional costs of management for somenon-asbestos-containing materials. All areas shouldbe accessed and inspected as far as reasonablypracticable (eg above false ceilings and insiderisers, service ducts, lift shafts, etc) or must bepresumed to contain asbestos. Any material whichcan reasonably be expected to contain asbestosmust be presumed to contain asbestos, and where itappears highly likely to contain asbestos, thereshould be a strong presumption that it does. Allmaterials which are presumed to contain asbestosmust be assessed.

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Type 2: Standard sampling, identification andassessment survey (sampling survey)

14 The purpose and procedures used in thissurvey are the same as for Type 1, except thatrepresentative samples are collected and analysedfor the presence of asbestos. Samples from eachtype of suspect ACM found are collected andanalysed to confirm or refute the surveyor’sjudgement. If the material sampled is found tocontain asbestos, other similar homogeneousmaterials used in the same way in the building canbe strongly presumed to contain asbestos. Lesshomogeneous materials will require a greaternumber of samples. The number should be sufficientfor the surveyor to make an assessment of whetherasbestos is or is not present. Sampling may takeplace simultaneously with the survey, or as in thecase of some larger surveys, can be carried out as aseparate exercise, after the Type 1 survey iscomplete.

Type 3: Full access sampling and identificationsurvey (pre-demolition/major refurbishmentsurveys)

15 This type of survey is used to locate anddescribe, as far as reasonably practicable, all ACMsin the building and may involve destructiveinspection, as necessary, to gain access to allareas, including those that may be difficult to reach.A full sampling programme is undertaken to identifypossible ACMs and estimates of the volume andsurface area of ACMs made. The survey is designedto be used as a basis for tendering the removal ofACMs from the building prior to demolition or majorrefurbishment so the survey does not assess thecondition of the asbestos, other than to note areasof damage or where additional asbestos debris maybe expected to be present.

16 Although different types of survey can bespecified and used depending on the circumstances,it is important that the building owner, employer andthe surveyor know exactly what type of survey is tobe carried out, what the specifications for each typeare, and in which areas they are to be used. It isrecommended that the type of survey usedconforms to a standard (eg this MDHS), otherwiseinterpretation of the survey reports will be difficultand the management plan produced may notadequately minimise the risks involved. It is possiblethat at larger premises a mixture of survey types willbe appropriate – eg a boiler house due fordemolition will require a Type 3 pre-demolitionsurvey, while offices at the site may only have aType 1 presumptive survey. Similarly, a system-builtproperty may start with several Type 2 surveys, butother similar premises may be evaluated using a

Type 1 survey. Therefore it is important that there isa clear statement and record of the type of surveysthat are to be carried out, including the reasons fortype selected, where they are to be carried out, andan estimate of the number of samples to becollected.

SURVEY PLANNING

Procedure

17 Once the type of survey has been established,it is important to gather information and plan thesurvey. Survey planning should include the followingfive steps:

■ preliminary site meeting and walk-through;

■ desk-top study to plan survey;

■ survey plan (including details of samplingstrategy, if appropriate);

■ risk assessment for the conduct of the survey;and

■ specification of the method for recording andpresenting data.

At some sites it may not be necessary or possible toinclude all of these steps (eg small premises, firedamaged premises and pre-purchase surveys etc).

Preliminary site meeting and walk-through

18 If a third party is carrying out a survey for theemployer, a preliminary meeting is important toestablish how to record and use the results of thesurvey, so the employer can manage the risk. It isalso an opportunity to explain further the type ofsurvey and assessments which will be undertaken.Every site will have its own specific problemsrelating to safety issues and hazards, the availabilityof original and up-to-date plans, entry limitations tocertain areas etc. Whenever possible, currentaccurate plans of the building and the floor layoutshould be made available at an early stage. Ifcurrent or older plans are not available, a sketchplan will need to be made. All plans should bechecked for accuracy. These plans will be used torefer to and record the whereabouts of any suspectmaterial and the location of any samples taken foridentification. They should also be used to locateand record any sensitive or restricted areas andhazards.

19 A walk through the site should be made with aperson who knows the premises which are to besurveyed. The purpose is to get a better overall

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picture of the site and the problems involved. Thewalk-through can be used to check that any siteplans are up-to-date and room numbering/coding isadequate. It also allows any specific hazards whichthe survey personnel may encounter to berecognised and discussed to minimise any risks.Potential problems for access to ceiling voids andcrawl spaces can also be assessed, along with otherpotential sampling problems (eg sampling only whenthe area is otherwise unoccupied, materials ordecorations which cannot be disturbed, labelling ofsample locations, future placement of asbestoswarning labels, measures used to reduce dustrelease and clean-up, etc).

Desk-top study to plan survey

20 The aim of the desk-top study is to gatherinformation on the types, construction and ages ofpremises to be surveyed and current or formerequipment and types of processes carried out inthem (eg buildings constructed after 1974 areunlikely to contain sprayed asbestos fireproofing).Architects’ original plans and specifications andsubsequent plans for major changes orrefurbishment should also record where ACMs wereinstalled for fire protection, heat insulation ordecorative purposes. Previous plans, as well ascurrent plans, should be obtained where possible.

21 However, low density insulating board and otherasbestos-containing products are often used to giveincreased fire protection to structural beams andpillars, fire doors, risers, service ducts, stairwells,ceilings, lift shafts and also around heaters. Theseboards may not be readily observable as they maybe concealed or over-clad with other materials. Anyequipment requiring heat insulation such as boilers,furnaces, ovens, fires, storage radiators, heatexchangers, calorifiers as well as any connectingpipes, are the obvious places where asbestosinsulation is likely to have been used. Also, largemachinery may have asbestos-containing frictioncomponents such as clutches and brakes. Some ofthe products and product names of ACMs are listedin Table 1.

22 The current plans can be used to refer to andrecord the whereabouts of any suspect material andthe location of any samples taken for identification.The plans should also be used to locate and recordany sensitive or restricted areas. If no plans areavailable, additional work will be necessary to recordthe survey information accurately. There will also bea need for information on any previous asbestosremoval.

Survey plan and sampling strategy

23 After the preliminary site visit and desk studyhave been completed, a written plan for the mainsurvey can be produced. The plan will normallyspecify the following:

■ the buildings and areas to be included in thesurvey and any areas to be excluded;

■ the type of survey to be used (and where othertypes may be applicable);

■ any possible or known ACMs not to be includedin the survey;

■ the survey procedure;

■ the assessment method and the parameters tobe assessed (eg product type, location, extent,condition and accessibility of ACMs);

■ the information to be recorded and the methodand format to be used;

■ the quality assurance checks and procedures tobe undertaken;

■ any area where access was not possible; and

■ sampling method, number of samples andagreed arrangements for making good.

Specification of the method for recording andpresenting data

24 Both the form of the survey records and finalreport format should be documented and agreedwith the client before starting the survey.Consideration should be given to:

■ what data will be reported;

■ how they will be presented;

■ the way the survey data will be stored,accessed and updated (eg a paper copy in thesite manager’s office or a computer databaseaccessible on a network or the Internet);

■ the way photographic or video records andmarked-up plans will be stored and reported;

■ whether each room/area inspected should beindividually recorded; and

■ whether asbestos lookalike materials should berecorded.

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The survey report or abstracts from it should bepresented in a form that can be used as the basisfor an updatable register or log of ACMs. This logwill need to be readily accessible (eg in the estatesor building manager’s office) so it can be consultedprior to the authorisation of maintenance or remedialwork. A register or log can be more easily accessedand updated if it is stored electronically.

HEALTH AND SAFETY RISKS

Risk assessment for conduct of survey

25 Before carrying out a site survey, it is importantthat an assessment of the risks to the health andsafety of surveyors, sampling personnel and otheroccupants is carried out. Risk assessments shouldbe documented and must be available to the sitesurveyors. Often surveyors will be seeing the site forthe first time so will have little chance to evaluate thesite-specific hazards that are involved and will relyon the risk assessment made based on informationgathered during the preliminary site meeting andwalk-through. The client should be asked to provideinformation relating to any hazards specific to thesite. In addition to the hazards of asbestos, hazardswhich may be associated with asbestos surveyinginclude:

■ working at heights, in ceiling voids or on fragileroofs;11, 12

■ working on operable machinery or plant;

■ working in confined spaces;13

■ chemical hazards;14

■ electrical hazards;

■ biological hazards;14

■ noise hazards;15 and

■ lone working.

The risks to surveyors, sampling personnel andother occupants should be reduced to as low asreasonably practicable. In assessing the risks, theappropriate HSE guidance should be consulted.

Safe work procedures

26 Ideally a survey should be conducted withteam(s) of two persons. This has a number ofadvantages, for example, in assisting with carryingequipment such as step ladders, labelling of samplebags and documentation. In cases of remote or

dangerous locations (eg derelict buildings or itemsidentified in paragraph 25), a team of two should bespecified as a safety requirement. Teamworkingalso allows field training of new surveyors to becarried out in a supervised practical environmentand gives a better chance of finding ACMs. Furtherinformation on safe working procedures can befound in paragraphs 44-45.

Personal protective equipment

27 Disposable overalls, overshoes and glovesshould be worn when there is a likelihood ofasbestos contaminating the surveyor's clothing andduring bulk sampling. The overalls should be of thetype normally used for asbestos work and shouldhave a hood and elasticated cuffs and ankles. Theycan be worn over normal clothing but should becarefully removed after use by turning inside out,and be disposed of as asbestos waste. Care shouldbe taken to prevent the spread of asbestos. Forsome dirty or contaminated sites, Wellington bootswill be required, and these should be wiped orwashed clean if they become contaminated and/orafter sampling is completed. For some sites, morestringent decontamination procedures may benecessary (see paragraph 29).

28 Appropriate respiratory protective equipment(RPE) should be worn during sampling or whensurveying areas where the asbestos is likely to bedisturbed during the inspection (eg crawl tunnelsand above false ceilings). The survey and samplingpersonnel must have been properly trained in theselection, use and maintenance of respiratoryprotective equipment and follow the guidance givenin INDG288.11

Decontamination and disposal arrangements

29 If the surveyor has to enter areas where thereis a lot of contamination (eg thermal insulation incrawl tunnels, spray insulation in ceiling voids),clothing is likely to be particularly contaminated, soadditional safety precautions and decontaminationprocedures will be necessary. This may involve theuse of positive pressure respirators, transitprocedures and a hygiene facility, and theserequirements should be identified in the initial walk-round of the site. Alternatively, the area should bepresumed to be heavily contaminated with asbestos.

SURVEYING

Requirements

30 The success and usefulness of a survey isdependent on the specification and planning

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carried out and the training, experience anddiligence of the surveyor. When an area is notinspected, this must be recorded and presumed tocontain asbestos until it can be proven that ACMsare not present. It is important that the surveyor hasa good understanding of which products andmaterials are likely to contain asbestos and whereACMs are likely to be located. Experiencedsurveyors may discriminate between potentialasbestos and non-asbestos-containing materials insitu. This initial judgement will be tested by samplingand analysis in a Type 2 survey, but previousexperience is used to make a presumption in a Type1 survey. The surveyor should have strongevidence to support a reasoned argument forpresuming a material does not contain asbestos.The surveyor must also look out for evidence ofasbestos debris released by previous work, or evenduring installation or removal work (eg over-sprayfrom sprayed asbestos applications).

31 The survey will need to be carried out in amethodical and systematic way to ensure that allvisible or accessible areas are inspected. This willusually involve using either a top-down or bottom-upapproach for surveying the building and eachindividual area or room for ACMs. The outside of thebuilding should also be inspected. Larger premiseswill require more detailed survey procedures,particularly if there are several surveyors at work. Itmay also be appropriate to carry out a separatesurvey on the building services, machinery and anylarge floor and ceiling voids.

Types, location and appearance of asbestos-containing building products

32 Table 1 and Figure 1 summarise the main typesand uses of ACMs in the fabric of a building and infixed installations such as heating, water andelectrical systems. The table lists the main producttypes, their location and use, asbestos content, datelast used and common trade or product names. Theproduct types are listed approximately in order oftheir ability to release fibres assuming no surfacetreatments have been applied. The appearance ofthese products and where and how they are likely toappear in situ in buildings have been given in anillustrated annex (Annex 1) as an aid to identifyingpotential asbestos-containing materials.

Other products containing asbestos

33 Older consumer electrical products may alsocontain some ACMs (eg hairdryers, irons, toasters,washing machines, dishwashers, tumble dryers), butthe asbestos is not readily accessible and it is notpractical to inspect or sample for such asbestoswhich would constitute a very low risk. However,

products which are used for or require significantheat insulation should be considered during thesurvey. This will include simmering mats, ironstands, fire curtains and blankets, catalytic gasheaters, gas coal or log effect fires, all types ofwarm air, storage or radiant heaters, and cookerdoor seals. Older industrial machines and plant aremore likely to contain asbestos owing to their age orhigher performance requirements and are morelikely be serviced and subject to maintenance.Therefore, parts of machinery or plant which provideheat and electrical insulation, high performanceseals and frictional performance (driving belts,clutches, brakes and bearings) should be inspectedif readily accessible. It is not recommended that thesurveyor should sample or work on any machinery,unless qualified to do so. If sampling is not carriedout, they should be presumed to contain asbestosunless there is evidence to suggest they are non-asbestos materials.

What to assess and record

34 A Type 1 and 2 survey must assess and recordthe following, for each suspect or presumedasbestos material found:

■ product type;

■ location;

■ extent (or quantity);

■ asbestos type;

■ accessibility;

■ amount of damage or deterioration; and

■ surface treatment (if any).

The last three will not usually be required for a Type3 pre-demolition survey.

Presumed ACMs

35 If a sample is not taken, there must also be apresumption made whether the material is asbestosor non-asbestos. Surveyors may visually assess theedges and damaged areas of suspect materials andrecord the following:

■ whether visible fibres are present on closeinspection (see MDHS 7710);

■ the colour of the fibres, if visible; and

■ whether fibres are visually consistent withasbestos (eg form bundles with splayed ends).

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Some materials like textured plasters, paints andvinyl floor tiles may contain very fine dispersedchrysotile asbestos which may not be seen by eyeor with a magnifying glass, and these materials (ifold) will have to be presumed to contain asbestosunless they are sampled and carefully analysed by acompetent laboratory. As imported materials mayhave contained chrysotile asbestos until 1999 andlaboratories often miss the fine asbestos, someadditional checks may be necessary with thesetypes of materials. Other useful characteristics (egsurface texture, sound when knocked, warmth totouch, surface hardness/deformation with a probe)may also be used by experienced surveyors to helpcompare the material to other materials they havepreviously encountered and had samples identified.Unless the surveyor is convinced that there isadequate evidence to support a reasonedargument that the material is non-asbestos-containing (eg plaster, plasterboard, wood etc), apresumption or strong presumption is made that it isan ACM.

Asbestos type

36 It is also necessary to decide which types ofasbestos are present for the material assessment. Ifa material is not sampled and a similar product hasnot been identified in the survey, the most likelyasbestos type must be allocated based on theproduct types and age in Table 1. Close inspectionof the fibres, if visible in the product, will give someadditional clues to the type of asbestos (see MDHS7710). In general, there should be a reasonedargument for it not being crocidolite or anotheramphibole asbestos.

BULK SAMPLING STRATEGY

37 Bulk sampling may be carried outsimultaneously with the survey or carried out later asa separate sampling exercise. Often for smallsurveys it is convenient to take samples whilesurveying, while for larger buildings sampling maybe carried out as a separate exercise when thebuilding is empty. After a visual examination toassess any apparent areas of different material,samples of about 3-5 cm2 area and through theentire depth of the ACM should normally be takenwith the aim of collecting one or more sampleswhich are representative of the whole material.Sampling should not be carried out where there isan electrical hazard or if it will damage the criticalintegrity of a roof, gutter, pipe etc. An equipment listis given in Annex 2.

38 The sampling strategy (see paragraphs 39-43)will be based on the types of ACMs present, and for

larger premises there is often an advantage insampling after a Type 1 survey has been completed,so the numbers and locations of the samplesrequired can be specified. In general, forhomogeneous manufactured products containingasbestos, it can be assumed that the asbestos isuniformly distributed throughout the material, andone or two samples will suffice, eg boards, sheets,cement pipes, textiles, ropes, friction products,plastics and vinyls, mastics, sealant, bitumen roofingfelt and gaskets. Insulation materials are generallyless homogeneous as they were applied on site andtheir composition depended on the availability ofsupply. Subsequent repairs and patching may addto this variability and increase the number ofsamples required. In addition, substantial over-spraycontamination and debris may have been produced.Often a single sample may be all that is required toconfirm the suspicion that a homogeneous materialis asbestos and to make a presumption that itapplies to other material of the same type. However,for non-homogeneous materials and for somepresumed non-asbestos materials, additionalsampling may often be needed, to reduce thepossibility of false negatives which may lead touncontrolled exposures. The following samplenumbers are suggested, but may be adapteddepending on the site and the circumstancesprevailing.

Spray coatings, encapsulated sprays and bulkmaterials

39 These are usually, but not always,homogeneous (under any encapsulate) and usuallytwo samples should be sufficient if taken at eitherend of the sprayed surface, unless the installation isparticularly large or there are areas of repairs oralterations.

Pipe/thermal insulation

40 Pipe insulation is often highly variable incomposition, especially where there is a change incolour, size and texture or there is evidence ofrepairs or modifications. The number of samplescollected will be dictated by the planned andsubsequent activities. If a plant room is due forcomplete refurbishment, a few samples of provenasbestos materials may be sufficient to condemn theentire plant room to be stripped as asbestos. If,however, most of the insulation is apparently non-asbestos, it may require more than a few samples to‘prove’ that all the insulation is asbestos-free. Forindividual pipe runs or boilers needing repair orreplacement, two samples may be sufficient,provided that there is no sign of earlier repairs orchanges to the insulation.

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leas

e if

unse

aled

, par

ticul

arly

if k

nock

ed o

r th

esu

rfac

e is

abr

aded

or

dela

min

ates

from

the

unde

rlyin

g su

rfac

e. D

ust r

elea

sed

may

then

accu

mul

ate

on fa

lse

ceili

ngs,

wiri

ng a

ndve

ntila

tion

syst

ems.

'Lim

pet'

(als

o us

ed fo

r no

n-as

best

ossp

rays

).

The

eas

e of

fibr

e re

leas

e of

ten

depe

nds

onth

e ty

pe o

f lag

ging

use

d an

d th

e su

rfac

etr

eatm

ent.

Ofte

n w

ill b

e en

caps

ulat

ed w

ithca

lico

and

pain

ted

(eg

PV

A, E

VA

, Lat

ex,

bitu

men

or

prop

riety

pol

ymer

em

ulsi

ons

orP

VC

, Neo

pren

e so

lutio

ns),

eg

'Dec

adex

'fin

ish

is a

pro

prie

ty p

olym

er e

mul

sion

. Aha

rder

che

mic

al-/

wea

ther

-res

ista

nt fi

nish

iskn

own

as 'B

ulld

og'.

Tab

le 1

:A

sbes

tos-

cont

aini

ng m

ater

ials

in b

uild

ings

(lis

ted

in a

ppro

xim

ate

orde

r of

eas

e of

fibr

e re

leas

e)

Asb

esto

s co

nte

nt

and

typ

e/d

ate

last

use

d

Usu

ally

pur

e as

best

os e

xcep

t for

lini

ng/b

ag.

Mat

tres

ses

and

quilt

s w

ere

usua

lly fi

lled

croc

idol

ite o

r ch

ryso

tile.

Aco

ustic

insu

latio

nm

ay c

onta

in c

roci

dolit

e or

chr

ysot

ile.

Spr

ayed

coa

tings

usu

ally

55%

-85%

asbe

stos

with

a P

ortla

nd c

emen

t bin

der.

Cro

cido

lite

was

the

maj

or ty

pe u

ntil

1962

. M

ixtu

re o

f typ

es in

clud

ing

croc

idol

ite u

ntil

mid

-197

1. A

sbes

tos

spra

y ap

plic

atio

ns w

ere

used

up

to 1

974.

All

type

s of

asb

esto

s ha

ve b

een

used

.C

roci

dolit

e us

ed in

lagg

ing

until

197

0.A

mos

ite w

as p

hase

d ou

t by

the

man

ufac

ture

rs d

urin

g th

e 19

70s.

Con

tent

varie

s 6-

85%

. Var

ious

ad

hoc

mix

ture

s w

ere

hand

-app

lied

on jo

ints

and

ben

ds a

nd p

ipe

runs

. Pre

-for

med

sec

tions

wer

e w

idel

y us

ed,

eg '8

5% m

agne

sia'

con

tain

ed 1

5% a

mos

ite,

'Cap

osil'

cal

cium

sili

cate

sla

bs a

nd b

lock

sco

ntai

ned

8-30

% a

mos

ite w

hile

'Cap

osite

'se

ctio

ns c

onta

ined

~85

% a

mos

ite. B

lank

ets,

felts

, pap

ers,

tape

s an

d ro

pes

wer

e us

ually

~10

0% c

hrys

otile

.

Lo

cati

on

/use

Bul

k lo

ose

fill i

nsul

atio

n is

now

rar

ely

foun

d bu

t may

be

enco

unte

red

unex

pect

edly

, eg

DIY

loft

insu

latio

nan

d fir

e-st

op p

acki

ng a

roun

d ca

bles

betw

een

floor

s. M

attr

esse

s an

d qu

ilts

used

for

ther

mal

insu

latio

n of

indu

stria

l boi

lers

wer

e fil

led

with

loos

e as

best

os. P

aper

bag

s/sa

cks

wer

e al

so lo

ose-

fille

d an

d us

ed fo

rso

und

insu

latio

n un

der

floor

s an

d in

wal

ls.

The

rmal

and

ant

i-con

dens

atio

nin

sula

tion

on u

nder

side

of r

oofs

and

som

etim

es s

ides

of i

ndus

tria

lbu

ildin

gs a

nd w

areh

ouse

s.A

cous

tic in

sula

tion

in th

eatr

es, h

alls

etc.

Fire

pro

tect

ion

on s

teel

and

rein

forc

ed c

oncr

ete

beam

s/co

lum

nsan

d on

und

ersi

de o

f flo

ors.

Ove

r-sp

ray

of ta

rget

are

as is

com

mon

.

The

rmal

insu

latio

n of

pip

es, b

oile

rs,

pres

sure

ves

sels

, cal

orifi

ers

etc.

11

Asb

esto

s b

oar

ds

'Mill

boar

d'

Insu

latin

g bo

ard

Insu

latin

g bo

ard

in c

ores

and

linin

gs o

f com

posi

tepr

oduc

ts

Pap

er, f

elt

and

card

bo

ard

Asb

esto

s 'M

illbo

ard'

has

a h

igh

asbe

stos

cont

ent a

nd lo

w d

ensi

ty s

o is

qui

te e

asy

tobr

eak

and

the

surf

ace

is s

ubje

ct to

abr

asio

nan

d w

ear.

'Mill

boar

d'.

AIB

can

be

read

ily b

roke

n, g

ivin

g si

gnifi

cant

fibre

rel

ease

. Als

o si

gnifi

cant

sur

face

rele

ase

is p

ossi

ble

by a

bras

ion,

but

sur

face

is u

sual

ly p

aint

ed o

r pl

aste

red.

S

awin

g an

d dr

illin

g w

ill a

lso

give

sig

nific

ant

rele

ases

.

'Asb

esto

lux'

, 'T

urna

sbes

tos'

, 'LD

R',

'asb

esto

s w

allb

oard

', 'in

sula

tion

boar

d'.

Mar

ine

boar

ds k

now

n as

'Mar

inite

' or

'Shi

pboa

rd'.

Can

be

brok

en b

y im

pact

; sig

nific

ant

surf

ace

rele

ase

poss

ible

by

abra

sion

, but

usua

lly p

aint

ed o

r pl

aste

red.

Saw

ing

and

drill

ing

will

als

o gi

ve s

igni

fican

t rel

ease

s.

'Asb

esto

lux'

.

Pap

er m

ater

ials

, if n

oten

caps

ulat

ed/c

ombi

ned

with

in v

inyl

,bi

tum

en, o

r bo

nded

in s

ome

way

, can

easi

ly b

e da

mag

ed a

nd r

elea

se fi

bres

whe

nsu

bjec

t to

abra

sion

or

wea

r (e

g w

orn

floor

ing

surf

ace

with

pap

er b

acki

ng).

Asb

esto

s pa

per,

asb

esto

s fe

lt, ‘N

ovilo

n’flo

orin

g, D

uras

teel

lam

inat

es, v

inyl

asb

esto

stil

e, r

oofin

g fe

lt an

d da

mp-

proo

f cou

rse

etc.

'Pax

felt'

. 'V

icer

oy' (

foil-

coat

ed p

aper

).'S

erva

l'.

Cro

cido

lite

was

use

d in

som

e m

illbo

ard

man

ufac

ture

bet

wee

n 18

96 a

nd 1

965;

usua

lly c

hrys

otile

. Mill

boar

ds m

ay c

onta

in37

-97%

asb

esto

s, w

ith a

mat

rix o

f cla

y an

dst

arch

.

Cro

cido

lite

used

for

som

e bo

ards

up

to19

65, a

mos

ite u

p to

198

0, w

hen

man

ufac

ture

cea

sed.

Usu

ally

15-

25%

am

osite

or

a m

ixtu

re o

fam

osite

and

chr

ysot

ile in

cal

cium

sili

cate

.O

lder

boa

rds

and

som

e m

arin

e bo

ards

cont

ain

up to

40%

asb

esto

s.

Cro

cido

lite

used

for

som

e bo

ards

up

to19

65, a

mos

ite u

p to

198

0, w

hen

man

ufac

ture

cea

sed.

16-4

0% a

mos

ite o

r a

mix

ture

of a

mos

ite a

ndch

ryso

tile.

Asb

esto

s pa

per

can

cont

ain

~10

0%ch

ryso

tile

asbe

stos

but

may

be

inco

rpor

ated

as a

lini

ng, f

acin

g or

rei

nfor

cem

ent f

or o

ther

prod

ucts

, eg

roof

ing

felt

and

dam

p-pr

oof

cour

ses,

ste

el c

ompo

site

wal

l cla

ddin

g an

dro

ofin

g (s

ee a

sbes

tos

bitu

men

pro

duct

sbe

low

), v

inyl

floo

ring.

Asb

esto

s pa

per

is a

lso

som

etim

es fo

und

unde

r M

MM

F in

sula

tion

on s

team

pip

es.

'Mill

boar

d' w

as u

sed

for

gene

ral h

eat

insu

latio

n an

d fir

e pr

otec

tion.

Als

ous

ed fo

r in

sula

tion

of e

lect

rical

equi

pmen

t and

pla

nt.

Use

d fo

r fir

e pr

otec

tion,

ther

mal

and

acou

stic

insu

latio

n, r

esis

tanc

e to

moi

stur

e m

ovem

ent a

nd g

ener

albu

ildin

g bo

ard.

Fou

nd in

ser

vice

duct

s, fi

rebr

eaks

, inf

ill p

anel

s,pa

rtiti

ons

and

ceili

ngs

(incl

udin

gce

iling

tile

s), r

oof u

nder

lay,

wal

llin

ings

,ext

erna

l can

opie

s an

d po

rch

linin

gs.

Fou

nd in

fire

doo

rs, c

ladd

ing

infil

lpa

nels

, dom

estic

boi

ler

casi

ngs,

part

ition

and

cei

ling

pane

ls, o

ven

linin

gs a

nd s

uspe

nded

floo

r sy

stem

s.U

sed

as th

erm

al in

sula

tion

and

som

etim

es a

s ac

oust

ic a

ttenu

ator

s.

Use

d fo

r el

ectr

ical

/hea

t ins

ulat

ion

ofel

ectr

ical

equ

ipm

ent,

wiri

ng a

ndpl

ant.

Als

o us

ed in

som

e ai

rco

nditi

onin

g sy

stem

s as

insu

latio

nan

d ac

oust

ic li

ning

.A

sbes

tos

pape

r ha

s al

so b

een

used

to r

einf

orce

bitu

men

and

oth

erpr

oduc

ts a

nd a

s a

faci

ng/li

ning

toflo

orin

g pr

oduc

ts, c

ombu

stib

lebo

ards

, fla

me-

resi

stan

t lam

inat

e.C

orru

gate

d ca

rdbo

ard

has

been

used

for

duct

and

pip

e in

sula

tion.

12

Asb

esto

s p

rod

uct

Tex

tile

sR

opes

and

yar

ns

Clo

th

Gas

kets

and

was

hers

Str

ings

Fri

ctio

n p

rod

uct

s

Res

in-b

ased

mat

eria

ls

Driv

e be

lts/c

onve

yor

belts

Eas

e o

f fi

bre

rel

ease

an

d p

rod

uct

nam

es

Wea

ving

red

uces

fibr

e re

leas

e fr

ompr

oduc

ts, b

ut a

brad

ing

or c

uttin

g th

em

ater

ials

will

rel

ease

fibr

es, l

ikel

y to

degr

ade

if ex

pose

d, b

ecom

ing

mor

e fr

iabl

ew

ith a

ge. I

f use

d w

ith c

aulk

ing,

fibr

es w

ill b

een

caps

ulat

ed a

nd le

ss li

kely

to b

e re

leas

ed.

Fib

res

may

be

rele

ased

if m

ater

ial i

sab

rade

d.

May

be

dry

and

dam

age

easi

ly w

hen

rem

oved

. Mai

nly

a pr

oble

m fo

rm

aint

enan

ce w

orke

rs.

'Klin

gerit

', 'L

ion

join

ting'

, 'P

erm

anite

', 'C

AF

' -co

mpr

esse

d as

best

os fi

bre

or 'I

t' in

Ger

man

gask

ets.

Low

fria

bilit

y, d

ust m

ay b

uild

up

with

fric

tion

debr

is.

Low

fria

bilit

y, e

xcep

t whe

n w

orn

to e

xpos

ete

xtile

.

Asb

esto

s co

nte

nt

and

typ

e/d

ate

last

use

d

Cro

cido

lite

and

chry

sotil

e w

ere

wid

ely

used

due

to le

ngth

and

flex

ibili

ty o

f fib

res.

Oth

erty

pes

of a

sbes

tos

have

occ

asio

nally

bee

nus

ed in

the

past

. Chr

ysot

ile a

lone

sin

ce a

tle

ast 1

970.

Asb

esto

s co

nten

t app

roac

hing

100

% u

nles

sco

mbi

ned

with

oth

er fi

bres

.

All

type

s of

asb

esto

s ha

ve b

een

used

in th

epa

st.

Sin

ce th

e m

id-1

960s

the

vast

maj

ority

has

been

chr

ysot

ile.

Asb

esto

s co

nten

t app

roac

hing

100

%.

Var

iabl

e bu

t usu

ally

aro

und

90%

asb

esto

s,cr

ocid

olite

use

d fo

r ac

id r

esis

tanc

e an

dch

ryso

tile

for

chlo

r-al

kali.

Som

e ga

sket

mat

eria

ls w

ill c

ontin

ue to

be

used

afte

ras

best

os p

rohi

bitio

n ta

kes

effe

ct.

Str

ings

hav

e as

best

os c

onte

nts

appr

oach

ing

100%

.

30-7

0% c

hrys

otile

asb

esto

s bo

und

inph

enol

ic r

esin

s. U

sed

up to

Nov

embe

r 19

99.

Chr

ysot

ile te

xtile

s en

caps

ulat

ed in

rub

ber.

Lo

cati

on

/use

Use

d as

lagg

ing

on p

ipes

(se

eab

ove)

, joi

ntin

g an

d pa

ckin

gm

ater

ials

and

as

heat

-/fir

e-re

sist

ant

boile

r, o

ven

and

flue

seal

ing.

Cau

lkin

g in

bric

kwor

k.P

laite

d as

best

os tu

bing

in e

lect

ricca

ble.

The

rmal

insu

latio

n an

d la

ggin

g (s

eeab

ove)

, inc

ludi

ng fi

re-r

esis

ting

blan

kets

, mat

tres

ses,

and

pro

tect

ive

curt

ains

, glo

ves,

apr

ons,

ove

ralls

etc

. C

urta

ins,

glo

ves,

etc

wer

eso

met

imes

alu

min

ised

to r

efle

ct h

eat.

Use

d in

dom

estic

hot

wat

er b

oile

rs to

indu

stria

l pow

er a

nd c

hem

ical

pla

nt.

Use

d fo

r se

alin

g ho

t wat

er r

adia

tors

.

Tra

nspo

rt, m

achi

nery

and

lifts

, use

dfo

r br

akes

and

clu

tch

plat

es.

Eng

ines

, con

veyo

rs.

13

Cem

ent

pro

du

cts

Pro

filed

she

ets

Sem

i-com

pres

sed

flat

shee

t and

par

titio

n bo

ard

Ful

ly c

ompr

esse

d fla

tsh

eet u

sed

for

tiles

,sl

ates

, boa

rd

Pre

-for

med

mou

lded

prod

ucts

and

ext

rude

dpr

oduc

ts

Like

ly to

rel

ease

incr

easi

ng le

vels

of f

ibre

sif

abra

ded,

han

d sa

wn

or w

orke

d on

with

pow

er to

ols.

Exp

osed

sur

face

s an

d ac

idco

nditi

ons

will

rem

ove

cem

ent m

atrix

and

conc

entr

ate

unbo

und

fibre

s on

sur

face

and

shee

t lap

s. C

lean

ing

asbe

stos

-con

tain

ing

roof

s m

ay a

lso

rele

ase

fibre

s.

Asb

esto

s ce

men

t, T

raffo

rd ti

le, '

Big

six'

,'D

oubl

esix

', 'S

uper

six'

, 'T

win

twel

ve',

'Com

bine

d sh

eet',

'Gle

n si

x', '

3'' &

6''

corr

ugat

ed',

'For

t', 'M

onad

', 'T

roug

hsec

','M

ajor

tile

and

Can

ada

tile'

, 'P

anel

she

et',

'Cav

ity d

ecki

ng'.

Rel

ease

as

for

prof

iled

shee

ts.

Fla

t bui

ldin

g sh

eets

, par

titio

n bo

ard,

‘Poi

lite’

.

Rel

ease

as

for

prof

iled

shee

ts.

Asb

esto

s-co

ntai

ning

roo

fing

slat

e (e

g'E

tern

it', '

Tur

ners

', 'S

peak

ers'

), 'E

verit

e',

'Tur

nall'

, 'D

iam

ond

AC

', 'J

M s

late

', 'G

lasa

lA

C',

'Em

alie

, Efle

x', '

Col

ourg

laze

','T

hrut

one'

, 'W

eath

eral

l'.

Rel

ease

as

for

prof

iled

shee

ts.

'Eve

rite'

, 'T

urna

ll', '

Pro

men

ade

tiles

'.

10-1

5% a

sbes

tos

(som

e fle

xibl

e sh

eets

cont

ain

a pr

opor

tion

of c

ellu

lose

).C

roci

dolit

e (1

950-

1969

) an

d am

osite

(19

45-

1980

) ha

ve b

een

used

in th

e m

anuf

actu

re o

fas

best

os c

emen

t, al

thou

gh c

hrys

otile

(us

edun

til N

ovem

ber

1999

) is

by

far

the

mos

tco

mm

on ty

pe fo

und.

As

for

prof

iled

shee

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chr

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ome

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ood

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els

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for

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l cla

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erm

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ling

tow

er e

lem

ents

.

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titio

ning

in fa

rm b

uild

ings

and

infil

lpa

nels

for

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ing,

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g in

indu

stria

l bui

ldin

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ativ

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nels

for

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h pa

nels

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eath

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ger

mat

eria

ls a

re r

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ecki

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late

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gro

ller-

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ing

rinks

, lab

orat

ory

wor

ktop

s).

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le tr

ough

s an

d co

ndui

ts. C

iste

rns

and

tank

s. D

rain

s an

d se

wer

pres

sure

pip

es. F

enci

ng. F

lue

pipe

s.R

ainw

ater

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pone

nts

(fas

cias

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fits,

etc)

. Ven

tilat

ors

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eath

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indo

wsi

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oxes

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th p

anel

s, d

rain

ing

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ds,

extr

actio

n ho

ods,

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ings

,pr

omen

ade

tiles

etc

.

14

Asb

esto

s p

rod

uct

Oth

er e

nca

psu

late

dm

ater

ials

Tex

ture

d co

atin

gs

Bitu

men

pro

duct

s

Flo

orin

g

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nfor

ced

PV

C

Rei

nfor

ced

plas

tic a

ndre

sin

com

posi

tes

Eas

e o

f fi

bre

rel

ease

an

d p

rod

uct

nam

es

Gen

eral

ly fi

bres

are

wel

l con

tain

ed in

the

mat

rix b

ut m

ay b

e re

leas

ed w

hen

old

coat

ing

is s

ande

d do

wn

or s

crap

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ff.'A

rtex

', 'W

onde

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', 'S

uret

ex',

'New

tex'

,'P

ebbl

ecoa

t', 'M

arbl

ecoa

t'.

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re r

elea

se u

nlik

ely

durin

g no

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use

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oofin

g fe

lts, d

pc a

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ased

seal

ants

mus

t not

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burn

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mov

al.

See

felts

and

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ers.

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re r

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se is

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ikel

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zard

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r no

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con

ditio

ns. F

ibre

may

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elea

sed

whe

n m

ater

ial i

s cu

t, an

d th

ere

may

be

subs

tant

ial r

elea

se w

here

floo

ring

resi

due,

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ticul

arly

pap

er b

acki

ng, i

spo

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-san

ded.

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ilon'

, 'S

erva

l asb

esto

s'.

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y ha

rd, f

ibre

rel

ease

unl

ikel

y.

Fib

re r

elea

se is

unl

ikel

y.

Fib

res

unlik

ely

to b

e re

leas

ed, l

imite

dem

issi

ons

durin

g cu

tting

.'S

inda

nyo'

, 'S

ilum

inite

', 'F

eroa

sbes

tos'

.

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or e

mis

sion

s w

hen

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ing,

mos

tas

best

os d

egra

des

with

fric

tiona

l hea

t.

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esto

s co

nte

nt

and

typ

e/d

ate

last

use

d

3-5%

chr

ysot

ile a

sbes

tos.

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ysot

ile a

dded

up

to 1

984

but n

on-

asbe

stos

ver

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ere

avai

labl

e fr

om th

em

id-1

970s

.

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ysot

ile fi

bre

or a

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tos

pape

r(a

ppro

xim

atel

y 10

0% a

sbes

tos)

in b

itum

enm

atrix

, usu

ally

8%

chr

ysot

ile.

Use

d up

to 1

992.

Adh

esiv

es m

ay c

onta

in u

p to

a fe

w p

er c

ent

chry

sotil

e as

best

os. U

sed

up to

199

2.

Up

to 2

5% a

sbes

tos.

Nor

mal

ly 7

% c

hrys

otile

.

Pap

er b

acki

ng a

ppro

xim

atel

y 10

0%ch

ryso

tile

asbe

stos

. Use

d up

to 1

992.

Abo

ut 2

% a

sbes

tos.

1-10

% c

hrys

otile

asb

esto

s.

Pla

stic

s us

ually

con

tain

1-1

0% c

hrys

otile

asbe

stos

. Som

e am

phib

oles

wer

e us

ed to

give

impr

oved

aci

d re

sist

ance

, eg

car

batte

ries.

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ins

wer

e re

info

rced

with

wov

ench

ryso

tile

clot

h, u

sual

ly c

onta

in 2

0-50

%as

best

os.

Lo

cati

on

/use

Dec

orat

ive/

flexi

ble

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ings

on

wal

lsan

d ce

iling

s.

Roo

fing

felts

and

shi

ngle

s, s

emi-r

igid

asbe

stos

bitu

men

roo

fing.

G

utte

r lin

ings

and

flas

hing

s.B

itum

en d

amp-

proo

f cou

rses

(dp

c).

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esto

s/bi

tum

en c

oatin

gs o

nm

etal

s. [C

ar b

ody

unde

rsea

ls.]

Bitu

men

mas

tics

and

adhe

sive

s(u

sed

for

floor

tile

s an

d w

all

cove

rings

).

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rmop

last

ic fl

oor

tiles

.

PV

C v

inyl

floo

r til

es a

nd u

nbac

ked

PV

C fl

oorin

g.

Asb

esto

s pa

per-

back

ed P

VC

floo

rs.

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nesi

um o

xych

lorid

e flo

orin

g us

edin

WC

s, s

tairc

ases

and

indu

stria

lflo

orin

g.

Pan

els

and

clad

ding

.

Use

d fo

r to

ilet c

iste

rns,

sea

ts,

bani

ster

s, w

indo

w s

eals

, lab

ben

chto

ps.

Bra

kes

and

clut

ches

in m

achi

nes.

Insulating board/ceiling tiles

41 Insulating board is usually homogeneous, butrepairs and replacement boards and tiles may havebeen fitted. One sample per room or every 25 m2 isusually adequate. If there is evidently more than onetype of panel, then representative samples of eachshould be taken. Larger installations completed atthe same time may require only a few tile samples tobe taken. Some replacement panels may look thesame. Inspection of the hidden side of the board ortile may, where access permits, reveal the tradename of the materials and/or differences in colourwhich indicate variations in the material.

Asbestos cement materials

42 These are homogeneous materials which arecommonly encountered as corrugated and flatsheets or as various moulded products. In olderbuildings, most pre-formed exterior cement sheetscan be strongly presumed to be asbestos, and onlylimited sampling is needed to confirm thepresumption. The risk from falls through asbestoscement roofs usually means that sampling isrestricted. If sampling is required, one sample ofeach type of sheet or product (eg gutters, down-pipes, etc) should be taken. Repeated sampling isnot usually necessary unless areas of replacedsheets are found. Asbestos cement (A/C) sheets arevisually very similar to their non-asbestos (fibre-cement) replacement. Fibre-cement replacementsheets are identifiable by a code ‘NT’ placed nearthe edge of the sheet, where they overlap. Somenewer asbestos sheets have the code ‘AT’ in asimilar position.

Other materials

43 Where there are distinct types of materials, thenone or two samples from each separate source willusually be adequate. Two samples arerecommended if there is more than a few squaremetres of material.

BULK SAMPLING PROCEDURES

Safe systems of work

44 All work to be carried out must have anadequate risk assessment of the survey site (seeparagraph 25) and the work must be carried outaccording to the procedures defined in the riskassessment. The work should minimise thedisruption to the client’s operations and must protectthe health and safety of all persons who may be atrisk (see CAWR). Sampling personnel must wearadequate personal protective equipment (PPE), as

determined by the risk assessment under CAWR(eg disposable overalls, overshoes/Wellington bootsand a suitable respirator). The type of materialsampled and the amount of disturbance of asbestosmaterial will dictate the type of respirator. Airborneemissions should normally be controlled by pre-wetting the material to be sampled, with waterand/or a suitable wetting agent. This may involvespraying the surface (eg boards and sheets) orinjecting (eg lagging and sprays). Shadowvacuuming (holding the suction inlet close to thearea where dust is being produced) with a Type H(BS 5415) vacuum cleaner should be used if wettingis likely to be incomplete (eg A/C, AIB boards, ropesand gaskets) or if it is not safe to do so (eg it maydrip into electrical installations). Special samplingprecautions are used for pipe lagging (see below).

45 The areas to be sampled inside buildingsshould as far as possible be unoccupied. Samplingshould not be undertaken in normally occupiedareas, but if in constant use, periods of minimaloccupation should be chosen. The nature of thearea, the likely release of dust and the proximity andnature of future work will dictate the precautionsrequired to prevent the spread of asbestos. Entry ofother people to any sampling area should berestricted or suitable warnings posted (eg a noticewith wording such as ‘Asbestos sampling inprogress – keep out’). Care should be taken tominimise the disturbance to the ACMs and any dustor debris that might be present. Surfaces onto whichasbestos debris may fall should be protected with asheet of impervious material such as polythenewhich can be easily cleaned by wet-wiping or usinga suitable type 'H' vacuum cleaner. All samples mustbe individually sealed in their own container or asealable polythene bag which is then sealed in asecond container or polythene bag. The samplearea should be left clean with no evidence of debrisfrom the sampling operation and any samplingpoints sealed to prevent the release of fibres. Avariety of methods are used to reseal the samplingpoint (eg tapes and fillers).

Sample and site labelling

46 Whenever a sample is collected, it should belabelled with a unique identifier that is also recordedin the survey documentation, records and site plansso that the sample origin can be traced at a laterdate. The sampling position at the site may also belabelled with the same identifier. Visual records suchas marked-up plans and/or photographic recordsshowing the location and extent of the sample arealso effective ways of recording the samplingposition and the location of the ACMs.

15

Bulk sampling

Spray coatings and bulk materials

47 If the coating is encapsulated, it can be pre-injected with liquid around the sampling area thencarefully cut with a sharp knife or scalpel in order tolift a small flap to retrieve a sample. If the spray isuncovered, both wetting (spraying surface andinjection) and shadow vacuuming may be necessaryto reduce airborne emissions. As sprays aregenerally homogeneous, a surface sample whichwill cause only a small disturbance should suffice.

Pipe insulation

48 The area to be sampled should be fully wettedfirst; injection techniques are recommended.Samples are taken with a core sampler whichshould penetrate to the full depth of the pipeinsulation. Proprietary types are available, butlaboratory cork borers are also suitable. It shouldinclude a plunger to remove the sample from theborer. The sample point hole should be made safeafter sampling (eg covered with tape or filled with asuitable inert filler), if the pipe is to remain in placeand the surface was originally intact. This helps tokeep the insulation in good condition and to preventdispersal of asbestos. The borer should have a ‘wet-wipe’ pushed down to form a plug inside the borerand another wrapped around the outside. The boreris then used to take a full-depth sample of theinsulation. The inner wet-wipe is used to seal thesurface of the insulation where the borer enters anddisturbs the insulation. The outer wet-wipe is used toclean the outside of the borer as it is withdrawn, andthe contaminated wet-wipe can be placed in thesample bag. The sample is removed by using aplunger to push the sample out into the polythenebag, complete with the wet-wipe. Further cleaningwill be required to completely clean the samplingequipment between sampling.

49 An alternative approach is to use core samplingtubes in which the sample is retained. Again thecore tube can be withdrawn through a wet-wipe andthen capped both ends and placed in a bag until itreaches the laboratory. Chicken-wire was oftenincluded within pipe insulation. This may hampersampling, and a thin core sample may need to betaken. Where there is pipe insulation which isobviously new and non-asbestos, the possibility ofdebris from an earlier asbestos strip beneath thenew insulation should be investigated.

Insulating board

50 Materials such as ceiling tiles or wall panels

should be inspected for areas of existing damage,where a sample can be collected more easily.Otherwise, a small sample should be taken from adiscrete location at the corner or edge of the panel,with a sharp knife or chisel blade to lever off asample.

Asbestos cement

51 Asbestos cement is usually very hard and it ispreferable to seek a damaged portion where it willbe easier to remove a small sample. The samplesize should be about 5 cm2 as it will be necessary tosearch for traces of amphibole asbestos such ascrocidolite. The sample should be obtained usingthe pliers or a screwdriver blade to remove a smallsection from an edge or corner. (Samples shouldnot be collected from roofs without specialsafety precautions to prevent falls through thefragile sheets.)

Gaskets, rope, seals, paper, felts and textiles

52 Samples can be taken using a sharp knife to cuta representative portion from the material.

Floor and wall coverings

53 Samples should be cut out with a sharp knife,usually taking one sample from tiles of each type orcolour present. The area should be cleaned aftersampling but the fibre release is likely to be verylow, unless the asbestos is present as a lining orbacking material.

Textured coatings

54 Samples should be obtained by carefullyscraping the coating with a screwdriver, directing thematerial into the sample container held below thesampling point.

Air sampling

55 Personal air sampling can be carried out tomeasure the exposures of survey and samplingpersonnel. Occasionally there may be a request forair sampling if the ACMs are a matter of sensitivityto the occupants. Such requests need carefulappraisal, as the area may already be contaminated,even before the bulk sampling is carried out. Theprocedures for reassurance air sampling asdescribed in MDHS 39/417 should be used.

Sample analysis and reporting

56 Analysis of the samples collected should becarried out and reported in accordance with the

16

method given in MDHS 7710 or an equivalentmethod. The laboratory report should for eachsample give a clear statement of whether asbestoswas found and the types of asbestos identified.

Survey report format

57 There are a number of ways the survey resultsmay be reported and presented. However, the reportmust clearly identify the:

■ location (eg building identifier, floor number orlevel, room identifier and position);

■ extent (area, length, thickness and volume, asappropriate);

■ product type (see Table 1);

■ level of identification (presumed, stronglypresumed or identified); and

■ asbestos type (chrysotile, amosite, crocidoliteetc).

If an assessment is carried out for a Type 1 or Type2 survey, the following will also be recorded:

■ accessibility;

■ amount of damage or deterioration; and

■ surface treatment (if any).

Laboratory results should be appended. Materialswhich have been sampled and found not to containasbestos after analysis also need recording as‘ASBESTOS NOT DETECTED’, as the asbestoscontent of these materials may be questioned infuture and it will save a great deal of time and cost ifthis has been clearly recorded in the first instance.The survey report or abstracts from it should bepresented in a form that can be used as the basis ofa register or log of ACMs and therefore should beboth accessible and updatable.

ASSESSMENT

58 The new duty to manage under CAWR willrequire a written plan to be produced, specifying themeasures to be taken to control and manage therisk from identified and presumed ACMs. Animportant stage of this process is to assess thepotential for fibre release of each ACM found. Tohelp make the assessment, in a structured andrecordable way, various tools have been developed.Algorithms and decision diagrams (decisiontrees/flow charts) have been widely used withvarious degrees of success. A standardised

assessment approach suitable for a Type 1 or Type2 survey is given below, based on a simplifiedadditive algorithm. For pre-demolition Type 3surveys, no assessment is necessary.

Material assessment algorithm

59 The four main parameters which will determinethe amount of fibre release from an ACM whensubject to a standard disturbance are:

■ product type;

■ extent of damage or deterioration;

■ surface treatment; and

■ asbestos type.

Each parameter is scored as: high = 3, medium = 2or low = 1; two categories also allow a nil score. Thevalue assigned to each of the four parameters isadded together to give a total score of between 2and 12. Presumed or strongly presumed asbestos-containing materials are scored as crocidolite (3),unless analysis of similar samples from the buildingshows a different asbestos type, or if there is areasoned argument that another type of asbestoswas almost always used (see paragraph 30 andTable 1). Examples of scoring for each parameterare given in Table 2.

60 Materials with assessment scores of 10 or moreare regarded as having a high potential to releasefibres, if disturbed. Scores of between 7 and 9 areregarded as having a medium potential, andbetween 5 and 6 a low potential. Scores of 4 or lesshave a very low potential to release fibres. Non-asbestos materials are not scored. The materialassessment score should be calculated andrecorded as part of the survey.

Risk assessment and management plans

61 The material assessment identifies the high-riskmaterials, that is, those which will most readilyrelease airborne fibres if disturbed. It does notautomatically follow that those materials assignedthe highest score in the material assessment will bethe materials that should be given priority for aremedial action. Management priority must bedetermined by carrying out a risk assessment whichwill take into account factors such as:

■ the location of the material;

■ its extent;

■ the use to which the location is put;

17

18

Table 2: Material assessment algorithm

Sample variable Score Examples of scores (see notes for more detail)

Product type 1 Asbestos-reinforced composites (or debris from product) (plastics, resins, mastics, roofing

felts, vinyl floor tiles, semi-rigid paints or decorative finishes, asbestos cement etc).

2 Asbestos insulating board, mill boards, other low density insulation boards, asbestos textiles, gaskets, ropes and woven textiles, asbestos paper and felt.

3 Thermal insulation (eg pipe and boiler lagging), sprayed asbestos, loose asbestos, asbestos mattresses and packing.

Extent of damage/deterioration 0 Good condition: no visible damage.

1 Low damage: a few scratches or surface marks; broken edges on boards, tiles etc.

2 Medium damage: significant breakage of materials or several small areas where material has been damaged revealing loose asbestos fibres.

3 High damage or delamination of materials, sprays and thermal insulation. Visible asbestos debris.

Surface treatment 0 Composite materials containing asbestos: reinforced plastics, resins, vinyl tiles.

1 Enclosed sprays and lagging, AIB (with exposed face painted or encapsulated), asbestos cement sheets etc.

2 Unsealed AIB, or encapsulated lagging and sprays.

3 Unsealed lagging and sprays.

Asbestos type 1 Chrysotile.

2 Amphibole asbestos excluding crocidolite.

3 Crocidolite.

Total

■ the occupancy of the area;

■ the activities carried on in the area; and

■ the likelihood/frequency with whichmaintenance activities are likely to take place.

62 The risk assessment can only be carried outwith the detailed knowledge of all the above.Although a surveyor may have some of theinformation which will contribute to the riskassessment and may be part of an assessmentteam, the duty holder under CAWR is required tomake the risk assessment, using the informationgiven in the survey and their detailed knowledge ofthe activities carried out within the premises. Therisk assessment will form the basis of themanagement plan (see paragraph 6). Furtherinformation on risk assessments and managementof asbestos will be available as separate HSEguidance.

DOCUMENTATION

Presentation of results

63 The results must be recorded in a clear,comprehensible, readily accessible and usable form.For all but the simplest survey, a computer databaseof suitable form is useful, as it enables the recordsto be kept up-to-date and to be readily accessible byvarious means (eg intranets, the Internet and otherdata transfer technologies). A database can be usedto record all the remedial work carried out and toprompt the building manager to carry out and recordany further inspections which are required. Somedatabases can also link digital picture images of asample and CAD plans.

Reporting requirements

64 The final report, depending on the type ofsurvey undertaken, may contain the followingsections:

■ general site and survey information;

■ survey report;

■ bulk analysis report;

■ material assessment/report.

If it is to be used as an integral part of themanagement plan, it will also require sections forreview and update.

65 General site and survey information shouldinclude:

■ the name and address of the organisationcarrying out the survey;

■ the names of the surveyors;

■ the name and address of the person whocommissioned the survey;

■ the name and address of the premisessurveyed;

■ the date of the report;

■ the date of the survey;

■ the purpose, aims and objective of the survey;

■ a description of the areas included in thesurvey;

■ a description of any areas excluded from thesurvey;

■ the survey method used (this MDHS and/orother documented procedures);

■ the type of survey undertaken (Type 1, Type 2or Type 3) and, if more than one type is used,where they apply within the premises;

■ any variations or deviations from the method;and

■ agreed exclusions and inaccessible areas.

66 The survey report should include a set ofmarked-up plans (quality will depend on what wasavailable) and a table, spreadsheet or databasecontaining the following descriptors:

■ location (eg building identifier, floor number orlevel, room identifier and position);

■ extent (area, length, thickness and volume, asappropriate);

■ product type (see Table 1);

■ level of identification (presumed, stronglypresumed or identified); and

■ asbestos type (chrysotile, amosite, crocidoliteetc).

For a Type 1 or Type 2 survey, the followingdescriptors should also be used:

■ accessibility;

19

■ amount of damage or deterioration; and

■ surface treatment (if any);

and the material assessment score or category(high, medium, low or very low) given.

For Type 2 and 3 surveys, a bulk analysis reportshould also be attached and include:

■ the name and address of the laboratory carryingout the bulk identification;

■ a reference to the method used;

■ the laboratory’s current United KingdomAccreditation Service (UKAS) accreditation forbulk asbestos analysis/sampling andaccreditation number;

■ a table or appendix summarising the results ofthe bulk analysis, including asbestos found ornot found and types identified, by sampleidentifier;

■ dates the bulk analysis was carried out andreported by the laboratory; and

■ the names and signatures of the analyst andany countersigning person.

QUALITY ASSURANCE PROCEDURES

67 The person or persons responsible forsurveying the premises have to use a high level ofsubjective assessment, and need adequate training,experience and time to carry out the survey. It isimportant that procedures used for conducting thesurvey, assessing and documenting the findings areclearly recorded. Organisations offering an asbestossurvey service should be able to comply with thestandard set out in EN 45004 (General criteria forthe operation of various types of bodies performinginspection). Accreditation to EN 45004 fororganisations undertaking asbestos surveys will beavailable from UKAS. Accreditation to ISO 17025 fororganisations sampling and/or analysing asbestos-containing materials is currently available fromUKAS. Please address enquiries to UKAS, 21-47High Street, Feltham, Middlesex TW13 4UN (tel:020 8917 8555). An individual proficiency module(P402) on building surveys and bulk sampling iscurrently offered through the British Institute ofOccupational Hygiene (BIOH), Suite 2, GeorgianHouse, Great Northern Road, Derby DE1 1LT (tel:01332 298087). Individuals can seek personalcertification to undertake asbestos surveys fromcertification bodies accredited to EN45013 byUKAS.

68 All surveying organisations should have andimplement policies for quality control and qualityassurance procedures. Quality control checks, suchas re-inspection (and, if necessary, correctiveaction) should be carried out on work in progress.The numbers of repeat samples should be adequateto detect errors and will vary with the complexity andvariety of the materials being surveyed. All theprocedures of a surveying organisation should bequality assured by carrying out audits of completedsurveys.

69 The laboratory should be able to demonstrateits competence to carry out bulk asbestos analysis(eg staff training records, certificates from externaltraining providers, testing programmes, participationin quality assurance schemes, satisfactoryperformance in national proficiency testingprogrammes, accreditation to ISO 17025 or be ableto demonstrate equivalence). The Asbestos inMaterials Scheme (AIMS) is the UK nationalproficiency testing programme for bulk asbestosanalysis. Individual analysts can also demonstratecompetency through training records andsatisfactory performance in a quality assurancescheme. It is recommended that samples orrepresentative sub-samples are kept after analysisfor at least six months to allow checks to be made.

REFERENCES

1 Health and Safety at Work etc Act 1974 HMSO1974 ISBN 0 10 543774 3

2 Control of Asbestos at Work Regulations 1987 SI 1987/2115 The Stationery Office ISBN 0 11 078115 5; Control of Asbestos at Work(Amendment) Regulations 1992 SI 1992/3068 TheStationery Office ISBN 0 11 025738 3; and Controlof Asbestos at Work (Amendment) Regulations1998 SI 1998/3235 The Stationery Office ISBN 0 11 080277 2

3 Management of health and safety at work.Management of Health and Safety at WorkRegulations 1999. Approved Code of Practice andguidance L21 (Second edition) HSE Books 2000ISBN 0 7176 2488 9

4 Workplace (Health, Safety and Welfare)Regulations 1992. Approved Code of Practice andguidance L24 HSE Books 1992 ISBN 0 7176 0413 6

5 Construction (Design and Management)Regulations 1994 SI 1994/3140 The StationeryOffice 1994 ISBN 0 11 043845 0

20

6 Proposals for amendments to the Control ofAsbestos at Work Regulations 1987: A newApproved Code of Practice and a minor amendmentto the Health and Safety (Enforcing Authority)Regulations 1998 CD 159 HSE Books 2000

7 Asbestos (Licensing) Regulations 1983 SI 1983/1649 The Stationery Office ISBN 0 11 037649 8; Asbestos (Licensing)(Amendment) Regulations 1998 SI 1998/3233 TheStationery Office ISBN 0 11 080279 9; A guide tothe Asbestos (Licensing) Regulations 1983 asamended L11 (Second edition) HSE Books 1999 ISBN 0 7176 2435 8

8 The control of asbestos at work. Control ofAsbestos at Work Regulations 1987. ApprovedCode of Practice L27 (Third edition) HSE Books1999 ISBN 0 7176 1673 8

9 Asbestos and man-made mineral fibres inbuildings: Practical guidance DETR (Fourth edition)Thomas Telford 1999 ISBN 0 7277 2835 0

10 Asbestos in bulk materials: Sampling andidentification by polarised light microscopy MDHS 77HSE Books 1994 ISBN 0 7176 0677 5

11 Selection of suitable respiratory protectiveequipment for work with asbestos INDG288 HSEBooks 1999 ISBN 0 7176 2456 0

12 Health and safety in construction HSG150 HSEBooks 1997 ISBN 0 7176 1143 4

13 General COSHH ACOP (Control of substanceshazardous to health) and Carcinogens ACOP(Control of carcinogenic substances) and Biologicalagents ACOP (Control of biological agents). Controlof Substances Hazardous to Health Regulations1999. Approved Codes of Practice L5 (Secondedition) HSE Books 1999 ISBN 0 7176 1670 3

14 Construction site health and safety checklistCIS17(rev) HSE Books 1996

15 Reducing noise at work: Guidance on the Noiseat Work Regulations 1989 L108 HSE Books 2000ISBN 0 7176 1511 1

16 Safe work in confined spaces. Confined SpacesRegulations 1997. Approved Code of Practice,Regulations and guidance L101 HSE Books 1997ISBN 0 7176 1405 0

17 Asbestos fibres in air: Sampling and evaluationby phase contrast microscopy (PCM) under theControl of Asbestos at Work Regulations MDHS39/4 HSE Books 2000 ISBN 0 7176 1113 2

18 Managing asbestos in workplace buildingsINDG223 HSE Books 1998

19 Work with asbestos insulation, asbestos coatingand asbestos insulating board. Control of Asbestosat Work Regulations 1987. Approved Code ofPractice L28 (Third edition) HSE Books 1999 ISBN 0 7176 1674 6

20 Controlled asbestos stripping techniques forwork requiring a licence HSG189/1 HSE Books1999 ISBN 0 7176 1666 5

21 Working with asbestos cement HSG189/2(Second edition) 1999 ISBN 0 7176 1667 3

ACKNOWLEDGEMENTS

This document was produced with the assistance ofWorking Group 2 of the Committee of FibreMeasurement. The members who contributed were:John Addison (John Addison Consultancy); TraceyBoyle (HSE); Garry Burdett* (HSL); Laurie Davies(Institute of Occupational Medicine); Andy Martin(United Kingdom Accreditation Service); JeanPrentice (McCrone Scientific Ltd); Bill Sanderson(Casella Science and Environment Ltd); DamianStear (HSE); and Barry Tylee (HSL). Contributors ofimages to Annex 1 included: British Gas, CasellaScience and Environment Ltd, HSE, HSL, McCroneScientific Ltd and SP Shutler Associates Ltd.

*Contact for queries. Health and Safety Laboratory,Broad Lane, Sheffield S3 7HQ.

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22

Note: This diagram does not showall possible uses and locations ofasbestos-containing materials. A detailed survey will be required toidentify all asbestos-containingmaterials present in a building.

●●●●●●

●●●●●

●●

●●●●

●●●●●●●●●●●●

●

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●

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●14

●24

●20

●25

●26

●31

●32

●34

●33

●36

●37

ROOF AND EXTERIOR WALLS1 Roof sheets, slates and tiles2 Guttering and drainpipe3 Wall cladding4 Soffit boards5 Panel beneath window6 Roofing felt and coating to metal wall cladding

BOILER, VESSELS AND PIPEWORK7 Lagging on boiler, pipework, calorifier etc.8 Damaged lagging and associated debris9 Paper lining under non-asbestos pipe lagging

10 Gasket in pipe and vessel joints11 Rope seal on boiler access hatch and between

cast iron boiler sections12 Paper lining inside steel boiler casing13 Boiler flue

CEILINGS14 Spray coating to ceiling, walls, beams/columns15 Loose asbestos in ceiling/floor cavity16 Tiles, slats, canopies and firebreaks above ceilings17 Textured coatings and paints

INTERIOR WALLS/PANELS18 Loose asbestos inside partition walls19 Partition walls20 Panel beneath window21 Panel lining to lift shaft 22 Panelling to vertical and horizontal beams23 Panel behind electrical equipment24 Panel on access hatch to service riser25 Panel lining service riser and floor26 Heater cupboard around domestic boiler27 Panel behind/under heater28 Panel on, or inside, fire door29 Bath panel

FLOORING MATERIALS30 Floor tiles, linoleum and paper backing,

lining to suspended floor

AIR HANDLING SYSTEMS31 Lagging32 Gaskets33 Anti-vibration gaiter

DOMESTIC APPLIANCES34 Gaskets, rope seals and panels in domestic boilers35 ‘Caposil’ insulating blocks, panels, paper,

string etc in domestic heater36 String seals on radiators

OTHER37 Fire blanket38 Water tank39 Brake/clutch lining

KE

Y

Figure 1 Asbestos buildingTypical locations for the most common asbestos-containing materials

23

●●19 29 ●21 ●

●1 ●2●3●4

●6

●5

●7 ●8●9●7 ●7 ●10 ●1112 ●13●15

●17●16 ●18 ●22

●23●27 ●28 ●30●35

●38●39

ANNEX 1: WHAT ACMs LOOK LIKE AND WHERETO FIND THEM

Examples of the main types, locations and uses ofACMs in premises are given below to help peoplerecognise materials which may contain asbestos.This is only a small selection of the range ofasbestos-containing materials used, but shouldcover many of the main uses of asbestos inpremises.

Product types

1 Loose asbestos insulation

Some fire doors contained loose asbestos insulationsandwiched between the wooden or metal facings togive them the appropriate fire rating. Looseasbestos was also packed around electrical cables,sometimes using chicken wire to contain it.Mattresses containing loose asbestos were widelymanufactured for thermal insulation. Acousticinsulation has been provided between floors by theuse of loose asbestos in paper bags, and in someareas near asbestos works it is not unknown forloose asbestos to have been used as a readilyavailable form of loft insulation.

1a Acoustic insulation in a ceiling void with a 'Jiffy bag'-typeconstruction, with paper container punctured for electrical wiring.

1b Loose insulation with paper cover degraded under a dancefloor.

2 Sprayed asbestos coatings

These are normally homogeneous coatings sprayedor trowelled onto reinforced concrete or steelcolumns or beams as fireproofing. Sprays were alsocommonly used on the underside of ceilings forfireproofing and sound and thermal insulation inmany high-rise premises. Warehouses and factoriescommonly had sprayed asbestos applied to walls,ceilings and metal support structures for fireproofingand thermal/anti-condensation insulation purposes.In some larger spaces, sprays were also applied towalls and ceilings for acoustic and decorativepurposes (theatres, cinemas, studios, halls etc). Thedepth of the spray depended on the fire rating andsubstrate, and may vary from 10 to 150 mm thick.The dry sprayed coatings may have a candyflossappearance if left untamped (rarely found in the UK).The wet sprayed/trowelled coatings are usuallydenser, and those with higher proportions ofPortland cement that have been well tamped can bequite hard. Surfaces may be sealed with anelasticised paint or proprietary encapsulant,sometimes reinforced with calico or man-made fibremesh, or left completely unsealed. Spray coatingsare vulnerable to accidental damage and also todelamination due to water leakage releasing debrisonto the floor and other horizontal surfaces.Overspray onto areas and recesses surrounding theobject that was being coated is common. Spraycoatings may have deteriorated significantly sinceinstallation and must be treated with caution.

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2a Cementitious sprayed chrysotile asbestos on a ceiling fordecorative and fireproofing purposes, showing evidence ofprevious damage and repair.

2b Poorly tamped sprayed chrysotile fireproofing on astructural steel beam holding up a concrete floor showing someoverspray onto the concrete and damage by electrical work.

2c Sprayed amosite fireproofing on steel roof support beams ina return air plenum showing signs of damage and wear at thebottom caused by access for maintenance.

2d Sprayed crocidolite asbestos (100 mm thick) applied asthermal insulation to the underside of an asbestos cement roof.From top to bottom, the encapsulated spray, the spray withoutencapsulant and removed spray from the A/C cement sheets.

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2e Close-up of the surface of sprayed amosite insulation (~40 mm thick) on the underside of an asbestos cement roof.

2f Sprayed crocidolite thermal insulation applied to externalwall cladding and enclosed behind non-asbestos wallboard.

3 Thermal insulation

Asbestos was widely used for thermal insulation ofpipes, boilers and heat exchangers. There are anumber of different types and forms of insulation,often with multi-layer construction. The simplestform to apply was pre-formed sections of asbestosinsulation made to fit the diameter of the pipe. Thesewould be strapped on and calico-wrapped andsometimes painted (eg ‘Decadex’ finish), or sealedwith a hard plaster (often asbestos-containing) togive protection against knocks and abrasion. Othertypes of asbestos-containing felts, blankets, tapes,ropes and corrugated papers were also used

instead of the pre-formed sections. For bends, joins,small sections of pipe and repairs, an asbestos-containing plaster was wet-mixed on-site and hand-applied to the areas. Larger installations were alsoinsulated with asbestos-containing plaster whichwas marketed as 'plastic', but various local nameswere used for this hand-applied insulation (eg‘muck’). Larger thicknesses of insulation would usepre-formed blocks (eg 'Caposil') which would bewired in place and various other coatings or layersapplied, depending on the insulation required. Veryhard-wearing coatings were known as 'Bulldog'finishes and may contain metal sheets and/orchicken wire reinforcement beneath a hard plasterfinish. External pipes may also be clad with sheetmetal or painted with bitumen to give additionalweatherproofing. As installers would often usewhatever materials were available to hand or instock, it is very common to find variations on thesame pipe or boiler. Particular attention must bepaid to bends and valves, or where it is evident thatrepairs have been made.

3a Asbestos-insulated water pipes in a loft, sealed and in goodcondition.

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3b Asbestos-insulated water pipes in a loft, showing evidenceof maintenance work damage, with detached pre-formed sectionsand calico wrapping.

3c Asbestos pipe lagging in a service riser, with calicowrapping and straps.

3d Asbestos pipe lagging on central heating pipes at theentrance of an underground crawl tunnel to adjacent premises.

3e Asbestos-lagged pipe with a polymeric encapsulant'Decadex’ finish.

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3f Asbestos-lagged boiler with a hard plaster coating.

3g High-pressure steam pipes in a power station with a‘Bulldog’ finish over 'Caposil' insulation blocks.

3h Badly degraded external asbestos-lagged pipe in anindustrial plant, with asbestos rope wound around the bends.

3i Example of hand-applied ‘hard set’ insulation, partiallyremoved from a pipe.

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4 Millboard

Millboard was used when a low-cost, relatively softlow-density board with modest mechanicalproperties but with good fire, insulation, thermal andelectrical properties could be specified. Generallyfound in industrial premises, but has been used asexterior lining to ventilation ducts and wascommonly used inside fire doors.

4a Removal of a piece of low density millboard from anelectrical cable box.

5 Asbestos insulating board (AIB)

Widely used in premises for internal partition wallsand linings and for fire protection, acoustic andthermal insulation. Suspended ceiling tiles wereoften made from AIB. Insulating boards come in arange of densities and can be subject to damage bythe use of moderate force (eg kicking). There maybe variations due to later construction of partitionwalls as part of a redevelopment or refurbishment.All kinds of combinations may be found andsurveyors must be alert for all possibilities. Areasaround lift shafts, stairwells and service risers inmulti-storey buildings were commonly lined or facedwith AIB or composites. Similarly, areas around gasfires and central heating boilers were alsoconstructed from AIB. Fire doors were also facedwith AIB to achieve the appropriate fire rating. AIB isusually found inside premises, but weather-protected exterior areas such as porches and soffitsmay contain AIB.

5a Typical use of AIB in system-built flats. The internal AIBpanel is visible behind a broken flat sheet (possibly asbestoscement) with textured coating (possibly chrysotile asbestos-containing) with MMMF insulation in between.

5b Painted AIB on ceiling.

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5c Painted AIB partition wall in a factory.

5d AIB around a service riser shaft (showing cut and uncutedges).

5e Painted AIB fire surround.

5f Painted AIB soffits.

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5g Painted AIB facing to a fire door with some damage aroundthe door furniture.

5h Perforated AIB ceiling tiles, showing a small area ofdamage around a light fitting.

5i Close-up of AIB with adhesive coating the top surface,showing the fibrous nature of the material.

6 Asbestos insulating board (AIB) incomposite materials

Asbestos insulating board was used in compositematerials and may be sandwiched between orsurfaced with non-asbestos products such as strawboard, plywood, metal mesh, sheet metal andplasterboard.

6a AIB inside an interior wall faced with plasterboard.

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7 Asbestos papers, felts and cardboard

Air conditioning trunking may be insulated internallywith ‘Paxfelt’ or externally with other asbestos-containing felt, cardboard and paper for acousticand heat insulation. Asbestos papers were widelyused to line the surfaces of other boards, ceiling tilesand sheet materials.

7a Example of the use of asbestos cardboard.

7b Foil-backed asbestos cardboard insulation inside a warm airheater.

7c Chrysotile paper-lined strawboard.

8 Asbestos textiles

Asbestos textiles were manufactured for primaryheat (eg insulation tapes and ropes) or fireprotection uses (eg fire blankets, fire curtains, fire-resistant clothing). Textiles were also used widely asa reinforcing material in friction products/composites(see section 15).

8a Example of asbestos tape on a domestic water heater.

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8b Asbestos gaiter between pipe flanges.

8c Asbestos fire blanket.

8d Asbestos rope seal in a domestic gas boiler.

8e Asbestos rope used as packing/seal where pipe passesthrough a wall.

33

9 Asbestos gaskets, washers and strings

A wide range of asbestos gaskets have beenproduced and used for sealing pipe and valve jointsin industrial plant, but they may also be found insome older domestic boilers etc. Asbestos stringwas widely used in the past by plumbers for sealingvarious screw thread joints.

9a Asbestos tape, string, rope and gasket in a maintenancerepair cabinet (note also the shiny vitreous appearance of a non-asbestos MMMF replacement tape to the left).

9b Asbestos string.

9c Gasket material adhering to a pipe flange.

10 Asbestos cement sheets and tiles used forroofing and cladding

Asbestos cement (A/C) has been extensively usedfor roofing and exterior cladding on industrial, publicand some domestic premises. Corrugated/profilesheets are commonly found, but flat sheets havealso been widely used for exterior and some interiorcladding (eg panels below windows and on walls inolder prefabricated housing).

10a Asbestos cement roof (seen from inside).

34

10b Asbestos cement roof (weathered exterior).

10c Asbestos cement vertical cladding.

10d Asbestos cement roofing slate.

10e View of the broken edge of an asbestos cement slateshowing chrysotile asbestos fibres embedded in the cementmatrix.

35

11 Moulded asbestos cement products

A wide range of moulded compressed A/C productshave been used inside premises (eg waste pipes,cold water tanks, flues etc) and outside premises(eg gutters, downpipes, flues, cowls, etc). Manyother items have been moulded from asbestoscement. Asbestos cement pipes are also usedunderground (eg from local drainage to regionalwater supply systems).

11a Asbestos cement water tank.

11b Asbestos cement flue from a domestic boiler.

11c Asbestos cement external flue, rain water gutter and profileroofing sheet.

11d Asbestos cement downpipe, hopper and profile sheet.

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11e Asbestos cement pipes.

12 Textured coatings, paints and plasters usedfor decorative effects

These were often manufactured containing up to afew per cent of asbestos. 'Artex', 'Wondertex','Suretex', 'Newtex', 'Pebblecoat' and 'Marblecoat'are examples of typical trade products, whichusually contained a few per cent of chrysotileasbestos.

12a Example of painted chrysotile textured coating on a ceiling.

13 Bitumen products

Bitumen-based roofing felts and damp-proof courseshave been widely reinforced by the addition ofasbestos, usually in the form of chrysotile paper.Bitumen-based wall and floor coverings were alsoproduced. Some mastics used to stick the bitumenproducts commonly had asbestos added to them toprovide flexibility. Other sealants also had asbestosadded to improve the performance of the product.

13a Weathered asbestos-containing roofing felt (less weatheredmaterial is black).

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14 Flooring products

Polyvinyl chloride (PVC or vinyl) tiles weremanufactured with added asbestos to meet a BritishStandard and often contain a few per cent (5-7%) ofvery fine chrysotile. Black and brown thermoplastictiles containing larger amounts and often visibleclumps of chrysotile were also produced. Sheet floorcoverings were sometimes backed with a thin layerof chrysotile paper (eg 'Novilon', a vinyl flooring,which was more common in Europe). Someunderfelts for carpets and linoleum were alsomanufactured containing asbestos. The masticswhich were used to bond the floor covering to thesurface could also contain asbestos. Some hard-wearing composite floors (eg magnesiumoxychloride) also contain about 2% of mineral fibreswhich could be asbestos.

14a Asbestos-containing vinyl floor tiles.

14b Cross-section of a broken thermoplastic floor tile showingsignificant chrysotile asbestos bundles. PVC/vinyl asbestos tilescontain short grades of finely divided chrysotile which may bedifficult to detect.

14c Asbestos paper-backed vinyl floor covering.

15 Asbestos-reinforced plastic/resincomposites and friction products

Asbestos-reinforced plastics and resin compositematerial were used for windowsills, capping forbanisters, school and laboratory worktops, toiletcisterns etc. The material is often black and has ahigh density and scratch resistance. Asbestostextiles were widely used as a reinforcing material infriction products (eg conveyor and fan belts, brakeand clutch linings). Older asbestos-containingcomponents may still be in use or present in vehiclerepair and maintenance workshops and stores.

15a Asbestos-reinforced plastic toilet cistern.

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15b Asbestos-reinforced windowsill.

16 Metal-asbestos composites

Flues for wood-burning stoves were commonlyconstructed from a metal-asbestos where theasbestos was added as insulation between the innerand outer layers of stainless steel to give a highdegree of insulation when passing through floorsand on the outside to prevent sudden cooling of theflue gases. 'Durasteel' metal panels were used toprovide a strong construction with a certain degreeof insulation, by incorporating a layer of asbestospaper.

16a Metal-clad asbestos flue pipe.

16b A ‘Durasteel’ panel.

17 Wall jointing tapes and fillers

Chrysotile textile tapes and webbing were used toreinforce wall joints before plastering. Several typesof wall plugs and some wall repair fillers hadasbestos added to give additional strength andflexibility. These are very difficult to locate as theyare integrated into the plaster finish.

17a Examples of chrysotile ‘scrim’ tapes.

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18 Domestic appliances and products

Many domestic appliances and products containasbestos insulation materials for thermal or electricalinsulation, including ironing boards, hairdryers, ovenseals, simmering plates etc. Some older electricfires and storage radiators and old gas fires withcatalytic elements or coal or log effect gas fires alsocontained ACMs.

18a Ironing board with asbestos cement sheet for iron rest.

18b ‘Caposil’ insulation from inside an old electric storageradiator.

18c Asbestos tape flash guards in a fuse box.

19 Industrial sites, factories and plant

Industrial sites (eg refineries, power stations,warehouses and factories) often contain substantialamounts of asbestos. Many of the examples givenfor spray, thermal insulation and pipe lagging comefrom industry. Higher-performance ACMs wereusually specified to cope with the highertemperatures and pressures prevalent at industrialsites. Some machinery may also incorporateasbestos gaskets and friction products (eg clutches,brake pads, drive belts and conveyor belts). Thehigher power requirements of industry also sawincreased use of asbestos insulation in electricalcables and switchgear.

19a Asbestos-insulated vessel and supply pipes in a factory.

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19b Asbestos gasket in an industrial pipe join.

19c Asbestos cloth and tape used as electrical insulation.

20 Dust and debris

Damaged materials will release asbestos dust anddebris. Often the source of the debris is obvious, butif poor removal and/or a poor level of clean-up hastaken place, only asbestos dust and debris will beleft. This will have accumulated on horizontalsurfaces and in difficult-to-clean areas. Poorremoval will also leave debris, either remaining insitu from where it should have been removed, or asscattered debris often in difficult-to-reach or cleanareas.

20a Asbestos debris in the bottom of a service riser.

20b Asbestos debris left on a walkway.

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20c Fibrous debris in a cable tray.

20d Sprayed asbestos debris released onto a suspended ceilingfrom cable installation work.

21 Non-asbestos replacement materials

Many materials in a building will be non-asbestos,and many of these can be readily recognised assuch. Later premises will often contain substitutenon-asbestos materials, which cannot bedifferentiated without analysis. Some examples aregiven below.

21a Glasswool insulation usually has a distinctive yellow colour,even after many years of gathering dust in lofts and roof spaces.A black layer of asbestos-containing roofing felt is, however,visible where the insulation has been removed and the woodenroof purling is encased in AIB. Rockwool and slagwool are alsowidely used and their darker brownish or grey colour maypossibly be confused with amosite, although the texture and fibresize is very different from asbestos. These wools may occur inblanket form, pre-formed bats and blown as loose insulation incavities. MMMF textiles have a vitreous shiny appearance (see9a) compared to asbestos textiles.

21b Fibre cement sheets are now widely produced as areplacement for asbestos cement sheets and are visually similar.However, each non-asbestos will be marked with a codecontaining the letters EUR NT (new technology). Some of thenewer A/C sheets are also marked with AT (asbestostechnology).

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ANNEX 2: EXAMPLE OF A SURVEY ANDSAMPLING EQUIPMENT CHECKLIST

Survey equipment

■ Site plan

■ Log book, organiser, computer

■ Step ladder

■ Camera (film or digital) with flash and preferablywith a date and number facility

■ Torch

■ Access keys to rooms and covers

■ Screwdrivers

Bulk sampling equipment

■ Pliers

■ Screwdrivers

■ Core samplers or cork borers

■ Aluminium foil or cloth tape

■ Stanley knife with spare blades

■ Hand-spray with diluted PVA or surfactant

■ Sample bags (polythene self-seal bags)

■ Sample point labels

■ Type H vacuum

■ Asbestos waste bags of the approved type

■ Warning signs: ‘Asbestos Sampling - KeepClear’

■ Wet-wipes and tissues

■ Polythene sheeting

PPE for sampling

■ Disposable overalls (hooded)

■ Disposable booties or Wellington boots

■ Disposable gloves

■ Respiratory protective equipment (as perassessment)

43

ANNEX 3: ASBESTOS WARNING LABEL

WARNINGCONTAINSASBESTOS

Breathing asbestosdust is dangerous

to health

Follow safetyinstructions

a

44 Printed and published by the Health and Safety Executive C25 08/02

9 78071 7 620760

ISBN 0-7176-2076-X

£18.00

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First published 2001Reprinted 2001,

2002 (three times)