Fire Safety Management: Evaluation of Means of Escape in Residential Building.

Yahya Mohamad Yatim*D. J. Harris, Ph.D. **

*Faculty of the Built Environment, Universiti Teknologi Malaysia, Johor, Malaysia. B-yahya@utm.my**School of the Built Environment, Heriot-Watt University Riccarton, Edinburgh, U.K.

(Paper presented at Asian PGS in Built Environment 2005, Faculty of The Built Environment, University of Malaya, Kuala Lumpur, Malaysia, 5th – 7th December 2005, proceeding, pg 93 - 100)

Abstract

This paper discusses the problems encountered in the provision of escape routes in residential buildings and qualitative evaluation of escape route design in residential buildings. Uniform Building By-Laws will be used to consider the aspects of the requirements as they relate to escape route design and fire safety in buildings. The issues of fire safety in residential buildings have not been given appropriate attention even though the statistics show that the instances of fire mainly occur in residential buildings. Among the issues explored is the trend in Malaysian buildings to install extra safety precautions in the form of an iron grill, which besides providing security against intruders creates an additional obstacle for occupants in the event of fire. Primary data for this research are collected using the checklist form of assessment which has been developed by the researcher. Fire safety attributes are identified and components of risk in building will be discussed, particularly risk to life and chances of successfully evacuating when fire breaks out in high-rise residential buildings.

Keywords: Fire safety, Escape Route, Risk Assessment, Evacuation.Article Type: Case Study, Comparative/Evaluating.

1.0 Introduction

The topic of Fire safety management has rapidly been developed by many researchers, especially fire safety in high-rise buildings. Fire safety is a broad area. However, studies concerning fire safety in high-rise residential buildings have not yet reached any firm conclusions. At present there is no quantitative method of assessing the adequacy of any escape route provided in a building other than by empirical means. The current method of providing means of escape from buildings is by specification and rules, i.e. rules that have evolved through time and are deemed to provide a satisfactory escape route (Shields & Silcock, 1989). In Malaysia Uniform Building By-Laws 1984 (LRB, 1993) is currently in use by the relevant authority to provide a satisfactory specification and guideline to building designers for their duty of work. It is nearly two decades since UBBL’84 was developed and it is still in use, and now is an appropriate time to review certain parts of it.

Defining fire safety is difficult and often results in a listing of factors that together comprise the intent. These factors tend to be of different sorts. Fire safety may be defined as goals and aims such as fire prevention, fire control, occupant protection, and so forth which normally can be found in the introductory section of building code and other fire safety legislation (Rasbash, et. al. 2004). According to Howarth, (1999), quoted by Derek et. al (1999) fire safety management can be defined as the application by a manager of policy, standards, tools, information and practices to the task of analyzing, evaluating and controlling fire safety.

Escape routes should be designed and constructed, and installed with adequate and suitable fire doors, so they will not be a death trap to building occupants. The main problem encountered in evacuation processes is when smoke enters into an escape route through a broken fire door and or through the gaps between the door and floor or the door and door frame. Another problem is traffic congestion during evacuation processes (Yatim, 1999). The

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provision of fire safety aspects in residential buildings, such as an active fire separation system, fire detection system, etc are at very minimum compared with other types of building, yet the fire risk to residential buildings is the highest among the other type of buildings. Statistics (1990 – 1999) show that 39.78% (9,512 cases) fire had occurred in residential buildings (Yatim, 2001).

2.0 Background of fire safety management.

Fire safety in building is an important issue but has not always been addressed sufficiently. People tend to only talk about fire safety in buildings, particularly in dwellings, when a fire tragic occurs and it has caused devastation. The National Building Code of Canada (NRC, 1995) defines fire safety as “an objective to reduce the probability that a person in or adjacent to a building will be exposed to an unacceptable fire hazard as a result of the design and construction of the building.” Design and construction of the building particularly escape routes and safe assembly, needs to be reviewed. The current practice whereby many building owners were inspired to harness security measures by putting an iron grill or an extra safety precaution such as double locked iron gates at the main entrance and other exit routes of their property, has increased the risk of being trapped if fire breaks out.

According to Ramachandran (1999) ‘Safety is the complement or antithesis of risk. Safety will be increased if the risk is reduced. There is no such thing as absolute safety. Some level of risk is virtually unavoidable. A building may be considered to be ‘very safe’ from fire if a sufficiently ‘low fire risk’ is associated with its structure, contents and occupants’. Occupants play a vital role in lowering the fire risk if their behaviour during evacuation exactly follows the theoretical frame work. But people’s behaviour is sometime unpredictable. According to Proulx (1995), elderly people and people with disabilities did not impede the evacuation since occupants who were mobility impaired waited in their unit to be rescued. The problem is if the building is not provided with a fire lift, firemen have to use the routes used by evacuees to rescue the mobility impaired persons. This will delay the evacuation process and increase the evacuation time.

If we observe Malaysia’s fire statistics, it is found that residential buildings are at the highest risk. Ten years of fire statistics in Malaysia (1990 – 1999) show that the average number of fire cases annually was about 15,499 cases. According to Datuk Dr. Ting Chew Peh (Statement in Berita Mingguan Oct. 26, 1996) fire claimed 840 victims annually with the average of 70 persons monthly. These are large numbers and worry many people. What went wrong has not yet been identified, because in many cases much evidence was burnt and the cause was impossible to trace. This is the risk that people have to face when they occupy high-rise buildings.

The National Fire Protection Association (NFPA, 2000) has developed a basic approach to minimise fire risk called Fire Safety Concepts Tree (FSCT). FSCT was derived to achieve the fire safety objectives, first for life safety and second for structure protection. There are two fundamental principles of FSCT, Prevention of Fire Ignition, and Managing Fire Impact. Prevention of fire ignition can be done in the early stages of the building design process by eliminating fire sources but to completely eliminate fire sources is impossible. No matter how much effort we put in to prevent ignition, fires continue to start. Once a fire has started, we have to manage the fire to minimize the impact on the people and structures. FSCT emphasizes fire suppression, control of combustion and containment of fire by construction. To manage the impact, FSCT emphasizes safeguard exposure and limit amount exposed. Among measures that can be applied to achieve the fire objectives are prevention of fire ignition, providing the means of detection, equipping with fire extinguishing equipment, controlling fire from spreading to the other parts of building and allowing time for people to evacuate from the building. Life safety is also influenced by the knowledge and experience that people have about the fire and fire spreading in buildings. With understanding of the fire behaviour and fire characteristics casualties can probably be reduced if appropriate measures have been taken when evacuating from the building. Therefore, research concerning the science of fire and how fire spreads in building or enclosed spaces is essential for high-rise residential buildings.

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3.0 Research Methodology

Observation case study. Research tool: Using checklist form Analysis method: Qualitative analysis technique. Benchmarks: Building Regulation: Approved document Part B – Fire safety UK and

UBBL ’84.

4.0 Some important issues in evacuation processes

The difficulty in escaping from building fire is largely due to several factors such as unnecessary fitted ‘safety precautions’ which can create obstacles, the design and construction of escape stairs which do not comply with the rules and regulations, the numbers of people occupying the building at one particular time exceeding the design factor, difficulty in finding the exact location of escape stairs due to unclear or no exit signage, smoke entering the escape stair, poor illumination system, etc. Other factors of equal importance are lack of facilities for disabled people to evacuate from the building, no alternative exit and no fire-fighting lift being provided. Those factors have a potential to increase the risks that people will be injured or be killed in building fire.

The cause of fire cannot be completely eliminated as stated by Mehaffey (1987) that, “Despite efforts to restrict the use of combustible material in buildings and to prevent ignition, fires will continue to start. Whether the fire grows and how quickly, depends to a large extent on the basic flammability of building materials and contents, as well as on the building design. The more quickly a fire develops, the less time occupants of the building have to escape”. Even though the potential for being killed or injured in a building fire cannot be completely eliminated, if the design of the building from the early stage was seriously considered, the consequences of fire threat would be minimised by optimising the resources available. How ever, fire safety in a building can be achieved through proven building design features intended to minimize the risk of harm to people from fire to the greatest extent possible (CWC, 2000). If sufficient data is available and analysis has been made to identify the top most risks associated with people in residential buildings during evacuation processes, probably the casualties and death of people in building fire can be eliminated. So what we should stress here is the ability of people to evacuate from the building in case of fire. Time is becoming the determining factor in life safety during building fires. The faster occupants are evacuated from the building the greater chances of saving their lives.

Therefore, there are some points that need to be emphasized in order to enhance the safety of the residential buildings:

Occupants need to be informed about the building fire as soon as fire started. Escape stairs should be located within the limits of travel distance. An alternative exit route should be provided even though the regulation may not say so in

certain circumstances. Obstruction by any means along the path to safe assembly area should be cleared. Most of the residential buildings have not been provided with the facilities to facilitate the

evacuation of disabled people. these facilities should be provided. People do not seem to react accordingly even if they have heard the sounder until they

saw, smelt or feel existence of fire. Therefore education concerning fire safety is very important.

5.0 The problems encountered in high-rise residential buildings.

No exit signage

In many high-rise residential building there is no exit signage to show the way out or to lead the occupants to the escape route. According to regulations a sufficient exit signage should

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be installed at every floor of the residential building. This problem can pose a danger to the person who is not really familiar with the building environment.

No smoke control system.

Every escape route and escape stair should be installed with a smoke control system to ensure the smoke is prevented from entering those places. Smoke control by means of a mechanical control system such as a pressurization system is not always installed as requested by the regulation. However there are natural ventilation systems provided at every floors but the opening was not according to the specification given in Building Regulation.

Obstacles in escape route

All escape routes should be cleared from any obstacles or any constructions which could delay the evacuation processes. In some buildings it was found that there are safety gates installed at the main entrance and at the alternative exit. The gates are controlled by electrical keys that are only be able to be opened by pushing the button located inside the building or by combination number from the outside of the building. At every floor there is another gate installed to separate the residential unit from the common area. The gate is locked from inside an only occupants of the units are able to open it. There are four units behind the gate and fitted with intercom facilities to each of residential units.

Ventilation system insufficiently installed or not at all.

Some of the buildings were designed with natural ventilation by means of ‘Open Space’ and some are using air brick ventilation on the escape stair wall. This will pose a danger to occupants because smoke may enter the escape stair due to low pressure created in the stair shaft cause by wind. In all observed residential buildings it was found that none of them are installed with a mechanical ventilation system even in enclosed escape routes. According to the regulations, they should be provided with an automatic opening ventilator or ventilators operated by smoke control for enclosed escape stair where the aggregate opening area is at least 1.5 m2.

Alternative stair and alternative escape window

An alternative stair and alternative route should be provided in high-rise residential buildings. According to By-Laws, at least one escape route should be provided if there are an alternative for the escape windows provided. The size of escape window situated in an external wall should be at least 0.33m2 and at least 450mm high and 450 mm wide. The bottom of the openable area should be not more than 1100 mm above the floor. In the observed building, there is only one escape stair without providing any alternative escape windows. However it has an alternative exit at the ground floor but both the main entrance and the alternative exit are separated from the common area fitted iron gates.

Automatic fire suppression system was not provided.

The most active fire fighting separation system provided in high-rise residential building is the dry riser. Some of the buildings are provided with the wet riser system and none were provided with an automatic fire suppression system even though the By-Laws has stated that it must be provided with an automatic life safety fire suppression system. For the system to be effective it is essential that an adequate water supply system should be provided too.

The maintenance for fire suppression system was not regularly being done.

Regular maintenance is essential to all fire suppression systems. This is to ensure that all systems are ready to use when needed. Fire suppression systems like dry riser, which is the most common system installed in many high-rise residential buildings, have a problem at a component called inlet breaching that the component to connect the system to fire engine to supply water to the entire system. The inlet breaching was either broken or stud with something due to vandalism.

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Illumination system or lighting system was insufficient.

The illumination system is a very important feature in escape route (corridors or similar) and escape stairs. The escape stair is a part of the escape route by definition, that it is part of a vertical evacuation process. Even though there is a lighting system installed in escape route, the location was either on the wall near to the ceiling or on the ceiling. When fire broke out, smoke will first fill up the upper part of the corridor and gradually spread downwards until the entire area is filled up with smoke. This restricts the light from reaching the floor and poses a handicap to the evacuees to see the path of evacuation. The alternative that probably could solve this problem is to apply an illuminated strip on the floor along the evacuation path and/or on the wall near to the floor edge.

6.0 Fire safety attribute in residential building.

The safety of people occupying high-rise residential buildings is not only the responsibility of the developers who built the buildings, but many parties to ensure that the building is safe for occupation. From the regulations passed in parliament, enforcement by the local authority and the building tenants themselves have the role to play to ensure that fire safety aspects are maintained at the highest possible standard. In this regard, there are ten points of fire safety attributes in high-rise residential buildings that need to be evaluated further to the greater extant that optimum protection and fire safety objectives can be achieved. Ten points of fire safety attributes are:

(1) Providing safe egress and protected zone for evacuation processes.(2) Escape stairs designed within the maximum travel distance permitted.(3) An alternative exit route provided in the building.(4) All fire doors and fire barriers constructed are able to stand fire for a reasonable time.(5) A place of safety or assembly area is designated and able to cater for a number of

evacuees.(6) Illuminated exit signage sufficiently provided.(7) Portable fire extinguishers and other types of fire suppression are provided and well

maintained.(8) Smoke control systems in an enclosed escape route and escape stairs are sufficiently

designed and installed to ensure the safe egress route is free from smoke.(9) Illumination system provided in escape route.(10) Dead end exit ways in residential units.

7.0 Component of risks in evacuating processes.

The component of risks in evacuation processes can be divided into five main categories; People (Knowledge & Experience), Legislation, Building Elements, Active Fire Protection, and Fire Plan and Evacuation Procedure. Figure 1.0 is a conceptual model of fire safety management (evacuation) in building. The model developed is based on risk identification (Fire Risk Index), fire safety attributes (Fire Safety Management Index), human factors (Occupation Density Factor), and casualty factors (Casualty Risk Index). The methodology used by Howarth and Chakib (1999) to determine the fire safety index in studying the fire safety management at passenger terminals is used to develop the concept model in figure 1.0. According to Howarth and Chakib, the lower the fire safety index, the better the fire safety aspect of the building. The fire safety indexes are:

Fire Safety Index (FSI) = Fire Safety Management Index (FSMI) x Fire Risk Index (FRI) x Occupant Density Factor (ODF) ……………………………..….(1)

FSMI = Ten points fire safety attributes in residential building where each element is rated out of five, thus giving a score of 50. It is calculated as the complement of the ratio of the score out of 50 for mathematical correctness.

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FRI = Potential sources of ignition in building, and fire load and flammable materials available in building is calculated where each element is rated out of five, thus giving a score of 50 as well.

ODF = Occupation Density Factor is the numbers of people occupied the building at one particular time divided by the building built-up area.

Fire Safety Index for Evacuation (FSIe).

The Fire Safety Index for Evacuation is calculated by modifying the equation (1) by putting in Casualty Risk Index (CRI) into the equation. CRI is the index that calculated by taking into account the Casualty Risks Element (CRE) comprising; (i) People’s knowledge & experience, (ii) Legislation and enforcement, (iii) Building elements and escape route design, (iv) Active fire protection installed in the building, and (v) Fire plan and evacuation procedure, and multiply it with the Evacuation Risk Element (ERE). Therefore formula to calculate the CRI is:

CRI = CRE x ERE ……………….……………………………………………………………...(2)

Evacuation Risk Elements (ERE) which had been identified in the high-rise residential buildings are:

(1) Quantity of fire load and combustible material stored in residential units.(2) Any kinds of obstacles that may possibly delay the evacuation process such as any

alteration or modification to the original design of escape route etc.(3) Operation of fire door installed in building.(4) Types of internal circulation within the buildings.(5) Escape stairs design and construction.(6) Probability of smoke and heat threaten evacuees.(7) Numbers of occupants occupied the building at one particular time.(8) Types of active fire fighting system provided in the building(9) Lighting system fixed in escape route(10) Location of escape stairs.

By multiplying equation (1) with equation (2), FSI become Fire Safety Index for evacuation (FSIe). Therefore the equation (1) becomes:

FSIe = (FSMI) x (FRI) x (ODF) x (CRI) ………………………..……………..……….……...(3)

Where: FSMI = 1 – X/50FRI = Y/50ODF = Z/ACRI = CRE x ERECRE = α/50ERE = β/50

X, Y, α and β are score point from the survey data which each question will be rated out of five. There are ten questions which giving a score of 50 maximum and 5 minimum for each categories.Z is number of people occupying the building at the survey time, andA is a built-up floor area of building in m2.

8.0 Conclusions and recommendations.

The study is continuing to evaluate and validate the proposed model to confirm with the professional experiences and research data. The FSIe mentioned above is still under development and at this stage data collection is still going on to produce the index table.

Fire safety index (evacuation) will be increased with the increase of fire risk in high-rise residential buildings. The increase or decrease of fire risk is mainly influenced by people’s

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knowledge and experience they have about the building fire, the legislation and enforcement by authority, the building element especially escapes route and fire barriers, and the active fire protection system installed and maintained up to the standard in the building.

The concept model in figure 1.0 explains that the evacuation procedure will be tougher and more problematic if the Casualty Risk Elements have not been thoroughly strengthened and properly installed in the building. For example if the knowledge about the building fire is less, then the volume of people (Knowledge & Experience) chamber becomes smaller and the volume of the Evacuation Procedure chamber becomes more. The same principle applies to the other elements. However, the model is still undergoing further development to strengthen both the qualitative and quantitative approach in order to make it viable and credible.

References.

Canadian Wood Council (CWC), (2000), Fire safety in Residential Buildings, Building performance bulletin, series 2. Pg. 3.

Derek, J. H, & Chakib, K, (1999), Fire Safety Management at Passenger Terminals, Disaster Prevention and Management Journal, Vol. 8, No. 5, pp 362 – 369, MCB University Press.

Howarth D.j.,Chakib Kara-Zaiti, (1999), Fire Safety Management at Passenger Terminals, Disaster Prevention and Management, Vol. 8, pp 362 – 369.

Howarth. D.J., (1999), Fire Safety management at Passenger Interchanges, M.Phil thesis, University of Bradford, Bradford.

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FIRERISK

Note:Solid line: Controlled Variable.Dotted line: Justifiable Variable and Expandable Boundaries.Arrow line: Stretch or Shrink Direction

Figure 1.0: Conceptual Model of Fire Safety Management (evacuation) in Building

People(Knowledge &

Experience)

Legislation & Enforcement

Building Elements & Escape Route

Design

Active Fire Protection System

Jabatan Bomba Malaysia, (2001), “Statistik Kes-Kes Kebakaran di Semenanjung Malaysia 1990 -1999”, Pusat Sumber Ibu Pejabat Bomba Malaysia.

Legal Research Board (LRB) (1993), Uniform Building By-Laws 1984, International Law Book Sevices.

Mehaffey, J.R., (1987),"Designing for Fire Safety: The Science and its Application to Building Codes", Seminars Paper presented in major cities across Canada.

National Fire Protection Association (NFPA), 2000, NFPA 101 – Life Safety Code Quincy, MA.

National Research Council (NRC), (1995), National Building Code of Canada, Ottawa, ON. Prolx, G., (1995), Evacuation Time and Movement in Apartment Building, Fire safety Journal 24, pp 229 – 246.

Ramachandran,G., (1999), Fire Safety Management and Risk Assessment, Facilities Journal, Vol. 17 No. 9/10, pp363 – 377.

Rasbash, D.J., Ramachandran, G., Kandola, B., Watts, J.M., Law, M., (2004), Evaluation of Fire Safety, John Wiley and Sons, England.

Shields, T.J. & Silcock, G.W.H., (1987), Buildings and Fire, Longman Scientific & Technical, New York. pg. 355.

Yatim, Y.M., (1999), High Rise Building’s Fire Hazard and Fire Prevention Action, National Journal Alam Bina (UTM), Jld. 02, No. 01, pp 33 – 40.

Yatim, Y.M., (2001), Fire safety in Buildings – Causes and Risks, Paper presented in National Construction Industry Symposium 2001, Sofitel and Palm Resolt, Johor. Malaysia.

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