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2017/18 Eğitim Seminerleri
Importance of Listings and Approvals for Foam Suppression Systems
Simon BarrattFebruary 2018
- 1) Brief Introduction to Foam……- Why do we use it? | How does it work? | Foam Types
- 2) Listings and Approvals
- 3) Fire Tests and Foam- Focus on “Topside” applications
Foam Systems - Agenda
2017/18 Eğitim Seminerleri
• Foam can be used to protect both Class A and Class B type fires
• Primary use is with flammable/combustible liquids (Class B)
+More efficient than waterWater alone may not work | Faster extinction | Less water needed
+Vapor suppressionPost-fire security | High resistance against re-ignition
Foam Systems – Why do we use?
2017/18 Eğitim Seminerleri
By adding foam to water it lowers surface tension which helps the foam solution spread across the liquid surface faster.
It also provides more contact area between the foam solution and the flammable liquid helping vapor suppression and cooling.
Foam Systems – How does it work?
2017/18 Eğitim Seminerleri
• The 2 most common foams currently used are AFFF and AR-AFFF
• Selection is based on if the commodity been protected has the ability to mix with water (Miscible)
• AFFF’s can only be used on Hydrocarbon risks where as an AR-AFFF can be used on both Hydrocarbon and Polar Solvent
• Both work by applying a “foam blanket” across the liquid which forms a barrier to prevent ignited vapors escaping
AFFF AR-AFFF
Foam Systems– Foam Types
2017/18 Eğitim Seminerleri
Important to select the right
kind of foam!!
AFFF on Acetone
(wrong)
AR-AFFF on Acetone
(correct)
Foam Systems – Foam Types
2) Listings and Approvals
Foam Systems
2017/18 Eğitim Seminerleri
Why do we need to use approved equipment?
• A foam system is made up of many components and therefore many variables.
• UL and FM have an approach of ensuring system components are working together through performance, compatibility and fire testing.
• This is an expensive process but necessary when providing the highest possible performance levels which ensures peace of mind for the end user
• Many design standards require listed equipment”
Foam – Listings and Approvals
2017/18 Eğitim Seminerleri
Foam – Rules and Standards
The use of recognised design standards is good practice.
NFPA 11 (Low, Medium & High Expansion Foam) is the most
commonly used and includes;
Low Expansion Foam Protection of :-
- Outdoor Storage Tanks
- Internal Flammable Liquid Hazards
- Loading Racks
- Diked and Non Diked Spill Areas
2017/18 Eğitim Seminerleri
Foam – Rules and Standards
NFPA 11 has many references to using “listed” equipment.
“3.2.4* Listed. Equipment, materials, or services included in a
list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of
products or services, that maintains periodic inspection of
production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, material, or service meets appropriate designated standards or has been tested and found suitable for a specified
Purpose”
2017/18 Eğitim Seminerleri
Main Product Approval Standards Summary
FM5130 – Approval Standard for Foam Extinguishing Systems
UL162 – Foam Equipment and Liquid Concentrates
Both these standards link Devices with compatible Foam Concentrate
EN13565-1 does not make a direct link between Devices and Foam
Foam Systems – Listings and Approvals
2017/18 Eğitim Seminerleri
Foam Systems – Listings and Approvals
High level of performance verification for the customer because;
•Foams are fire tested
•Foams are tested with discharge devices to obtain qualities and then retested on fires based on the data obtained.
•Hardware is tested for strength, corrosion and flow characteristics.
•Proportioning equipment is testing with each foam across several flow and pressure conditions.
•Continual audit of Documentation and Facilities
Product Approval Standards & Tests
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3) Fire Tests and Foam
“Topside” applications
- Flammable Liquid Storage
- Aircraft Hangar Protection
Foam Systems
2017/18 Eğitim Seminerleri
Foam Systems – Fire Tests and FoamFlammable Liquid Storage (Examples of Topside)
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•For the protection of Class B liquids in common applications such as refineries, tank farms, chemical storage and anywhere subject to the risk of spill fires.
•Where possible, approved or listed equipment should be used as an assurance that relevant fire tests to international test standards have been conducted.
•An FM approval or UL Listing is valid only when a Foam Concentrate is tested in conjunction with a Discharge Device. (commonly overlooked)
•Foam quality tests are made with a specific Foam and Discharge Device to obtain expansion and drainage values.
Foam Systems - Fire Tests and Foam
Foam “Top Side” Fire Tests
2017/18 Eğitim Seminerleri
The object of foam sampling is to obtain a sample of foam typical of the foam to be applied to burning surfaces under anticipated fire conditions.
A collector is designed to facilitate
the rapid collection of foam from
low-density patterns
“Qualities” measured are;
1)Expansion
2)25% Drainage
Foam Systems - Fire Tests and FoamObtaining Foam Qualities
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Video: Foam quality testing with
a 6” Foam Chamber and FP3% Foam
Foam Systems - Fire Tests and FoamObtaining Foam Qualities
2017/18 Eğitim Seminerleri
1)Foam samples are collected in a defined foam container (collection pot)
2)Once the pots are filled (as seen on the videos), a stopwatch is started
3)2 Pots are used to ensure a more consistent result and an average taken
4)After collecting a sample, the expansion is calculated based on weight
5)At the same time, the 25% volume is determined.
6)Foam SOLUTION is drained until the 25% volume is reached.
7) The time is noted and this is the “25% drainage time” value.
Foam Systems - Fire Tests and Foam
2017/18 Eğitim Seminerleri
*Once the foam qualities are obtained, they must be tested on a fire.
*Using the expansion and drain time foam quality obtained from the discharge devices (chamber, makers, monitors etc), this foam quality is then replicated through a calibrated fire hose nozzle.
Foam Systems - Fire Tests and Foam
2017/18 Eğitim Seminerleri
The video’s in the next slide show a comparison between a good foam quality and a low quality. This is the same test and same foam – only difference is the expansion / drainage.
The foam quality is primarily dictated by the discharge pressure.
This is why it is important to use approved equipment inline with the approval.
Foam Systems - Fire Tests and Foam
2017/18 Eğitim Seminerleri
21
Impact of Foam QualityFuel: AcetoneFlow rate: 23,3 l/min
Expansion: 3,4Drain time: 3:10
Expansion: 10,6Drain time: 13:50
H i g h F Q
Foam Systems - Fire Tests and Foam
L o w F Q
2017/18 Eğitim Seminerleri
Foam quality tests are made across the listed range of flows and pressures and results in a Listed / Approved range as per the example below.
Foam Maker with AFFF 3%S Foam. UL Listing
This approval is for 1 type of foam (AFFF3%) it represents around 60 foam quality tests!
Foam Systems - Fire Tests and Foam
Foam “Top Side” Fire Tests
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Foam Systems – Fire Tests and FoamAviation Hangar Protection (Examples of Topside
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Foam Systems – Fire Tests and Foam
• Use in Aircraft Hangars & Helidecks
• Grate Nozzles use the trenches required by NFPA 409 to prevent fuel spread
• No moving parts.
• Grate Nozzle discharges foam solution in a 360°, 180° or 90° uniform pattern.
Discharge Devices (Low Expansion) – Grate Nozzle
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Foam Systems – Rules and StandardsDischarge Devices (Low Expansion) – Grate Nozzle
Foam Qualities are obtained from the Grate Nozzle and then Fire Tested in the same way as other topside discharge devices.
2017/18 Eğitim Seminerleri
Foam Systems – Rules and StandardsDischarge Devices (Low Expansion) – Grate Nozzle
Additional tests required such as distribution (shown here an area test of 1 x 180° with adverse gradient.
2017/18 Eğitim Seminerleri
Foam Systems – Rules and StandardsVideo: CCCF Fire Testing
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1) The used of recognised design standards is strongly recommended
2) The use of (UL) Listed or (FM) Approved equipment is strongly recommended as it has been tested for its application and use.
3) Foam Concentrate should be used with its Listed/Approved Hardware
4) Designs should incorporate listed and approved equipment in accordance with the density and pressures published.
5) Foam Concentrates are not the same. The use of Listed and Approved Foam Concentrates gives confidence of performance in a fire condition
Foam Systems – Summary
2017/18 Eğitim Seminerleri
Thank you
teşekkür ederim
2017/18 Eğitim Seminerleri