NEBOSH Fire Safety key terms

A structured process of identifying fire hazards, deciding who could be harmed, evaluating existing controls and recording priorities for further action. It must be reviewed when conditions or occupants change.

The legal test for a fire risk assessment: it must identify significant hazards and risks, be proportionate to the premises, and be recorded where the law requires. It need not be perfect, but it must be defensible.

A hazard, risk or control weakness identified by a fire risk assessment that needs recording and action, because it could cause harm or breaches a legal duty. Trivial matters are excluded.

The level of fire risk remaining after existing and proposed controls have been applied. It must be judged tolerable or further action taken; it is what the assessment finally records as acceptable.

The order of preference for reducing risk: eliminate the hazard, substitute or reduce it, apply engineering controls, then rely on safe systems of work and finally personal protective equipment. Engineering measures outrank procedural ones.

As low as reasonably practicable: risk must be reduced unless the cost of further measures is grossly disproportionate to the safety benefit gained. It is a test of proportionality, not a demand for zero risk.

A legal standard requiring risk to be reduced unless the effort, time and cost of doing so are grossly disproportionate to the reduction in risk achieved. It underpins fire safety duties and enforcement decisions.

Measures that stop a fire starting, such as removing ignition sources, controlling fuel, avoiding accumulation of combustibles and maintaining electrical equipment. It is the most effective level of the hierarchy of control.

Measures that limit the consequences once fire occurs: detection, warning, compartmentation, suppression and safe escape. Protection does not stop ignition; it buys time and reduces loss.

The three elements needed for combustion: fuel, oxygen and heat. Removing any one prevents or extinguishes fire, which is the principle behind isolation, smothering and cooling.

An extension of the fire triangle adding the chemical chain reaction, needed to explain flaming combustion and the action of chemical extinguishing agents. It is used when selecting extinguishers and explaining inhibition.

Any energy source capable of starting combustion, including naked flames, hot surfaces, electrical arcing, friction sparks, smoking materials and self-heating materials. Identifying them is central to fire prevention.

The total quantity of combustible material in a space, expressed as calorific energy per unit area. High fire load increases fire severity and duration and influences compartment size and structural protection.

The lowest temperature at which a liquid gives off enough vapour to ignite briefly when a flame is applied. It indicates how readily a liquid presents a fire hazard.

The lowest temperature at which a material ignites spontaneously without an external ignition source. It matters for hot surfaces, drying processes and stored materials that can self-heat.

A liquid with a low flash point that readily produces ignitable vapour at normal working temperatures. Storage, dispensing and ventilation controls are based on this classification.

Any work producing heat, sparks or flame, such as welding, grinding or cutting. It requires a permit, fire watch, isolation of combustibles and post-work checks because it is a common ignition cause.

The automatic or manual means of sensing fire, such as smoke, heat or flame detectors. Detection must be appropriate to the expected fire type and environment to avoid delay or false alarms.

The installation that receives detection signals and gives audible and visual warning to occupants, and may trigger other systems. Its audibility, coverage and reliability are essential to life safety.

Systems that operate to detect, warn of or suppress fire, such as alarms, sprinklers and extinguishers. They require maintenance and testing to remain effective.

Built-in features that resist fire without needing to operate, such as compartment walls, fire doors, protected escape routes and structural fire protection. They work by containing fire and preserving escape.

The division of a building into fire-resisting cells by walls, floors and fire doors to limit fire and smoke spread. It protects escape routes, limits damage and gives time for evacuation.

The ability of an element of structure or construction to resist fire for a stated period, measured for stability, integrity and insulation. Ratings inform compartmentation and escape design.

A door assembly rated to resist fire and smoke spread when closed. It must be correctly fitted, kept closed or held open by approved devices, and not wedged, to preserve compartmentation.

The routes and features that allow occupants to reach a place of safety, including doors, stairs, corridors and signage. They must be adequate in number, width, travel distance and protection.

The distance an occupant must travel from any point to reach a place of relative safety. Limits depend on occupancy, fire risk and whether escape routes are protected.

A location where people are no longer at risk from fire or smoke, such as an open area outside the building or a protected refuge. Escape planning must define it clearly.

A protected space, often on an escape route or stair, where people who cannot use stairs can wait safely for assistance. It must be fire-resisting and communicate with the fire service.

An individual plan setting out how a specific person with additional needs will be warned and assisted to escape. It records named helpers, equipment and alternatives for when helpers are absent.

The planned approach to moving people out, such as simultaneous, phased or stay-put arrangements. The choice depends on building design, occupancy and fire engineering.

A designated safe location outside the building where occupants gather after evacuation so that a roll call can be taken. It must be clear of the building and of fire service access.

The process of accounting for people at the assembly point after evacuation. It identifies possible casualties and must be based on reliable visitor and staff records.

Lighting that operates on mains failure to illuminate escape routes, exits and key equipment. It supports evacuation when normal lighting is lost and requires regular testing.

Signs and markings that guide occupants to exits and indicate the direction of escape. They must be visible, correctly positioned and consistent with the actual escape routes.

A trained person responsible for checking areas, assisting evacuation, sweeping rooms and reporting at the assembly point. Wardens need clear duties, cover arrangements and regular drills.

A planned rehearsal of the emergency plan, used to test warning, evacuation, roll call and warden actions. Lessons learned must be recorded and acted upon.

The individual with legal duties to manage fire safety in premises, usually the employer, occupier or owner, or someone to whom duties are delegated. They must ensure assessment and control measures.

The arrangements for delivering fire safety, including policy, roles, planning, monitoring, training and review. It turns assessment findings into maintained, auditable practice.

A formal written authorisation controlling high-risk activities such as hot work or work in confined spaces. It records precautions, authorisation and completion checks.