The paper “ The Principles of Safe Escape Time and Required Safe Escape Time in Relation to Means of Escape” is a thrilling version of a math problem on engineering and construction. A fire outbreak in a building can cause devastating loss of human life if proper means of escape were not designed and implemented. Thus the British regulating agency has come up with principles that govern the design of building to ensure life safety as well provides means of processes, assessing and calculating the time to be used in saving lives in the building.
These regulations have taken into account people’ s behavior during a stay in the building, escape or on hearing fire alarm or exposure to smoke, heat, or fire affluent (Harold, Nelson, and Mowrer, 2002). It has also considered human condition or state of mind, for example, the reaction of children is different from that of normal adults as well as the reaction of patients in a mental hospital will react differently from occupants of a flat. This paper is going to critically look at the principles of safe escape time (ASET) and required safe escape time (RSET) in relation to means of escape.
In any design available safe escape time should be greater than the required safe escape time thus creating an appropriate margin of safety which is considered to take into account possible fire scenarios. During the design process care should be taken to ensure that occupants have adequate escape space and escape routes are protected from fire effluent, smoke, or heat which may impede escape or evacuation. It should be noted that escape routes are designed to enable occupants to escape without getting into contact with fire or associated effects like heat and smoke as recommended by BS 7974.B1 Means of escapeB1 of the Building Regulations is a concern with the safety of occupants of the building.
It requires designers of building to ensure that escape routes to be easy access to the building and be named fire exits, they should not be the same place with a normal entry route. This place should be lead to the safety area and outward of the building and should have illuminated signs.
In the case of story building, they should be evacuation stairs or lobby which has fireproof walls. Before the house is constructed, the standard recommends that risky profiles of occupants should be considered in order to calculate the width of the escape route. For example, the risky profile for a house whose occupants are expected to be awake throughout and familiar with the building will require a width of 3.3millimetres to 4.6 millimeters as minimum width per person for an escape route. This is incomparable to participants who are not familiar with the building or are likely to be asleep in the building.
However, the risky profile is determined by the materials that are used for construction. Materials that are likely to ignite fire fast will require a larger width as compared to those that are slow in catching fire. Therefore the requirement of B1 of building regulation highlights clearly options that are available to designers of buildings in designing escape routes.
British Standards Institution (BSI), 2004. BS 7974-6:2004, The application of fire safety engineering principles to fire safety design of buildings – Part 6: Human factors: Life safety strategies – Occupant evacuation, behaviour and condition, BSI, London, UK.
Chow, W.K., Fong, N.K. Pang, E, Lau, F. & Kong, K., 2006. Case Study for Performance-Based Design in Hong Kong. Paper presented at Society of Fire Protection Engineers – 6th International Conference on Performance-Based Codes and Fire Safety Design Methods on 14-16 June 2006 by Professor W.K. Chow
Chow, W.K., 2006. “Fire engineering approach and discussion on the design fire,” 6th International Conference on Performance-Based Codes on Fire Safety Design Methods, June 14-16, 2006, Tokyo, Japan – Paper to presented, June 2006.
Government of Ireland, 2006. Building Regulations 2006- Fire Safety. Dublin: Stationery Office
Harold, E., Nelson B. & Mowrer, F.W., 2002. “Emergency movement”, The SFPE Handbook of Fire Protection Engineering, National Fire Protection Association and Society of Fire Protection Engineers, 3rd edition, Quincy, Massachusetts, USA, pp. 3-367 – 3-380.
McGlennon, M., Montgomery, S. & Turner, B., 2009. Promoting Safe Egress and Evacuation for People with Disabilities. National Disability Authority
Purser, D. 2009. Human Fire Behaviour - and Performance-Based Design. Institution of Fire Engineers 2009 AGM Conference and Exhibition 1-2 July 2009< www.ife.org.uk/about/.../Purser_Human_Fire_Behaviour_24June09. >[ Accessed on 31st January 2013]
Purser D.A. & Bensilum, M., 2001. “Human behaviour in fire and other emergencies”, BRE Report 80893, Fire Safety Engineering Centre, UK.
Spearpoint, M., 2004. “The effect of pre-evacuation distributions on evacuation times in the Simplex Model”, Journal of Fire Protection Engineering, Vol. 14, No. 1, pp. 33-53.
Tzu-Sheng Shen, M. S, 2003. Building Planning Evaluations for Emergency Evacuation. A Dissertation Submitted to the Faculty of the Worcester Polytechnic Institute