Laboratories inherently present more fire risk than offices or other work spaces owing to the presence of the three elements needed to start and sustain a fire: heat, fuel and oxygen. Accordingly, laboratory managers must be vigilant about fire risk and safety as Lisa Bushby describes.
The Regulatory Reform (Fire Safety) Order 2005 requires that fire risk management is a structured and systematic process that identifies, implements and maintains the most appropriate measures to reduce risk from fires. To achieve this, a comprehensive fire safety risk assessment is required and a competent person should complete this activity with the help of the occupiers of the building.
Fire protection measures can be organised into two categories.
Passive fire protection attempts to contain fires and limit/slow their spread throughout a building through the use of structural features such as fire resistant walls, doors and floors. It is an inherent quality of the building construction and so it does not require anything or anybody to do anything. As such, it is failsafe by always being “on” and will operate as long as it is being maintained to the required standard. The primary design feature is to limit the spread of fire, heat and smoke and thus reduce risk to people and limit the damage.
Active fire protection includes those features which require something to trigger the response, for example, automatic fire detection and alarm systems, fire suppression and sprinkler systems, and other engineering features such as auto-closing ventilation in fume cupboards and air conditioning vents. Active fire protection is inherently less reliable than passive protection in that it requires a trigger to turn it on.
For the laboratory manager, a fire risk assessment means:
identifying fire hazards
identifying people at risk
assessing the risk and developing control measures
recording, planning, informing, instructing and training
Known as the fire triangle, the three elements needed to start and sustain a fire are heat (source of ignition), fuel and oxygen, and it is these three elements that need to be considered when identifying fire hazards.
An ignition source does not have to be a prolonged source of heat, such as a naked flame, which in a laboratory could be from a Bunsen burner or a flame gas cutter — other sources of heat can also cause fires if the conditions are right, such as hot plates, heating mantles, stirrer controllers or sparks from mechanical or electrical equipment.
It goes without saying that the majority of laboratories contain a variety of combustible materials, but it is not only flammable substances that pose a fire risk; any materials that burn easily can be considered fuel, such as paper, furnishings or rubbish.
The final element, oxygen, comes from the air, with approximately 21% of the earth’s breathable atmosphere consisting of oxygen, but laboratories are an example of an environment in which there are likely to be other oxygen sources, such as compressed gas cylinders, liquid oxygen or oxidising materials.
Therefore, the routine and regular use of flammable chemicals, combustible gases, volatile toxic solvents, electrical apparatus and, in some cases, the presence of a naked flame all combine to ensure that fire safety must be at the very forefront of the laboratory’s working procedures at all times.
People at risk
People working in the laboratory itself will be at risk of exposure to fire should a fire break out, but other occupants of the building and sometimes surrounding areas should also be considered.
Assessing the risk and developing control measures
Fuel sources, ignition sources and oxygen need to be managed.
If electrical equipment and wiring is faulty or used incorrectly, it can become a fire hazard and so should be taken out of service until it is repaired or replaced. Equipment should be maintained in good working order and be inspected regularly for signs of damage, faults and overheating.
Flammable liquids must be stored within approved metal flammable liquids cabinets with the material contained in the glass or plastic containers in which it was delivered. It is good practice to limit the total amount of flammable material in the laboratory at any one time.
Incompatible chemicals, such as oxidisers and flammables or acids and bases, should not be stored together.
Ensure Bunsen burners are not left unattended and that if it is necessary to leave a hot plate unattended, that a safety plan is in place.
Compressed gases should be stored in an upright position by a suitable retaining chain.
Even small spills should be cleaned up immediately. Any ignition of a spreading pool will produce a fire that quickly extends to the entire spill area. Particular dangers additionally arise if the spill enters the drains as an explosive atmosphere could form in an enclosed space.
Working, wherever it is possible, in a fume cupboard, will allow the sash to be closed and will give some protection if a fire should start.
Record, plan, inform, instruct and train
The details of the risk assessment should be recorded.
Adequate safety training includes instruction on what to do upon discovering a fire and what to do in the event of a fire alarm sounding.
Upon discovering a fire, the first action is to sound the alarm, all occupants should then immediately evacuate the area and go straight to the assembly point, a nominated person should then ring 999 (from a safe distance away) and inform the fire brigade, giving the exact location of the fire.
In the event of a fire alarm sounding, employees need to know to:
stop work immediately and calmly go to the nearest safe fire exit without stopping to collect belongings or use a lift
go straight to the assembly point
only go back into the building when someone in authority has said it is safe to do so.
The law requires that clear and unobstructed emergency and escape routes and exits are provided, and employees need to know that they have a duty to familiarise themselves with the escape routes and not to block any escape routes.
Doors along escape routes should be fire doors. These are used to minimise the spread of fire and smoke, and to help escape. Fire doors need to be kept closed.
Laboratory managers could nominate “fire wardens” and “fire marshals” as responsible persons to help in the event of a fire alarm sounding. Wardens can help ensure visitors or contractors unfamiliar with the premises are safely evacuated from two designated assembly points, they can prevent people from entering or re-entering the premises until it has been declared safe, and can provide relevant information to the fire services on arrival at the scene, such as the likely source or cause of fire and the location of all chemicals and combustible materials.
Managers should avoid the build-up of large quantities of paper and cardboard in their laboratories. Any of these materials not required for laboratory use should be stored elsewhere.
Risk assessment is a continuous process. New equipment, processes and people will affect the outcome of the assessment and so it should be reviewed both periodically and in the event of any significant change to the laboratory. Consider what is working well and where and what improvements can be made to ensure fire safety in the laboratory.