Promoting fire safety
In the rush to build and refurbish, fire protection measures may be overlooked. Dean McGrail, director, WSP Fire Engineering - Middle East & Asia, explains how the fire engineer can help.
Few people would fly in an aircraft if they knew that the safety systems were not operational, or get into a car if the brakes were in the process of being fixed. And yet, every day, workers in the UAE are exposed to hazards and risks in buildings due to incomplete or non-operational passive and active fire protection systems.
During the construction or refurbishment phases of a building, there is little assurance that fire safety systems are operational or that compartmentation is in place. Likewise, with large-scale projects, such as retail malls or high-rise schemes, the building owner is often keen to open the development in phases.
But, if the fire safety systems have been designed on the basis of a complete building, is there any guarantee that they will operate as intended? The construction or refurbishment phase of a building is one of the most dangerous stages in its lifecycle, not only from a fire safety perspective but also from the standpoint of other engineering disciplines.
While structural engineers have a legal obligation to demonstrate that the building will not collapse while under construction, fire engineers are not typically required to ensure it is safe for workers. However, this should not remove fire engineers from the legal obligation, as professional engineers, to make the client, contractor and developer aware of the hazards and risks associated with these phases of the building's life.
If the risks associated with the construction or refurbishment phase are viewed as a function of the building's total design life, then the mathematical influence of a couple of months' elevated risk would not result in the risk to life becoming intolerable. However, if looking at the construction or refurbishment period in isolation, it is likely that the risk level could be deemed to exceed tolerable limits.
The construction industry should therefore incorporate systems and procedures to mitigate the risk in these periods to tolerable levels, in the same way that a fire engineer would when considering deviations from standard guidance in a complete building. Active and passive systems, such as sprinklers, compartmentation and fire detection, are designed-in to ensure the safety of occupants when the building is complete. However, these systems may not be operational during construction, so alternative management protocols or physical systems need to be put in place to mitigate the residual risks.
Buildings under construction or refurbishment are, at some point, likely to be susceptible to one or all of the following issues: blocked or unprotected means of egress routes; incomplete compartmentation; active fire safety systems which are either not installed, incomplete or not commissioned; control systems which are not operational; lack of fire protection to structural members; poor implementation by management of fire safety drills and routines; hot working; and increased fire load from construction materials.
Fire safety measures
Buildings in the UAE are typically designed in accordance with US National Fire Protection Association (NFPA) codes. NFPA 241: Safeguarding construction, alteration and demolition operations, ÃƒÂ¢Ã¢â€šÂ¬Ã‹Å“prescribes minimum safeguards for construction, alteration, and demolition operations in order to provide reasonable safety to life and property from fire during such operations'. Fundamental to the application of this standard is the production of an overall fire safety programme, emphasising the following: good housekeeping; on-site security; installation of new fire protection systems as construction progresses; preservation of existing systems during demolition; organisation and training of an on-site fire brigade; development of a pre-fire plan with the local fire service; rapid communication; consideration of special hazards resulting from previous occupancies; protection of exiting structures and equipment from exposure fires resulting from construction, alteration and demolition operations.
In addition, NFPA 5000: Building construction and safety code, prescribes additional measures for the refurbishment of buildings.
The measures detailed in NFPA 241 and NFPA 5000 seem like commonsense. However, in the push to construct buildings on time and to budget, these simple measures may be overlooked and, in some cases, ignored.
The two NFPA standards provide a good basis for minimising the potential loss of life and damage to buildings during construction and refurbishment. However, fire safety professionals are aware that buildings do not always follow the requirements of prescriptive legislation and that different buildings require different solutions, not only when they are complete but also when under construction.
Perhaps the most important aspect in addressing fire safety during construction or refurbishment is to ensure that the solution adopted can compensate for the fire safety measure that is deficient. For example, the lack of a sprinkler system cannot be compensated for by emergency lighting, but the use of additional compartmentation or a fire detection and alarm system may be acceptable.
While the possibility of fire occurring in any building - whether under construction or refurbishment or completed - cannot be eradicated, the risk to construction workers, building occupants and firefighters needs to be dealt with in the same pragmatic way, with an assessment of the hazards and risks and the incorporation of systems and management procedures to mitigate these hazards and risks. Fire engineers need to make clients aware of the issues associated with the construction and refurbishment of a building. The public perception of a building can be damaged irrevocably if a fire occurs.