NEBOSH Fire Safety cheat sheet

UK framework: Regulatory Reform (Fire Safety) Order 2005 (England and Wales) imposes a duty on the 'responsible person' to carry out a suitable and sufficient fire risk assessment, apply prevention and protection measures, and record significant findings where 5 or more employees are employed (or a licence is in force).

Scotland uses the Fire (Scotland) Act 2005 and the Fire Safety (Scotland) Regulations 2006; Northern Ireland uses the Fire and Rescue Services (Northern Ireland) Order 2006 with the Fire Safety Regulations (NI) 2010 - duties are analogous but the enforcing authority and terminology differ.

Hierarchy of control applied to fire: eliminate the hazard (remove/replace flammable materials, avoid hot work), reduce (substitute less hazardous substances, minimise quantities), then protect (detection, compartmentation, suppression, escape).

The fire risk assessment is a continuous cycle: identify hazards, identify people at risk, evaluate/remove/reduce risk, record, implement and plan, then review and revise - review triggers include changes to work, new plant, building alterations, or a near miss.

Safety management system elements (Plan-Do-Check-Act): policy, organising (competent persons, clear roles), planning and implementing, measuring performance (audits, inspections, KPIs), and review/audit by senior management.

Competence is a legal expectation: the responsible person must appoint 'competent persons' with sufficient training, experience and knowledge; where in-house competence is absent, a competent external assessor must be used.

Enforcement tools: alteration/ enforcement notices, prohibition notices (serious personal injury risk), and prosecution; penalties include unlimited fines and up to 2 years' imprisonment for the most serious offences in England and Wales.

Records to retain: fire risk assessments and reviews, training records, drills and evacuation times, maintenance and testing of detection, alarms, emergency lighting and extinguishers, and statutory testing of gas/electrical installations.

Fire safety information must be provided to employees, contractors, temporary staff and, where relevant, residents and visitors - including emergency plan, location of exits, and the identity of fire marshals.

Risk = likelihood of ignition/ fire occurring x severity of consequence (life safety, property, business interruption); a common qualitative scale is 1-5 for each, giving a risk rating banded low/medium/high/very high.

Five-step model: (1) identify fire hazards - ignition sources, fuel, oxygen; (2) identify people at risk - including those asleep, disabled, lone workers, visitors, contractors; (3) evaluate, remove or reduce risk and protect from remaining risk; (4) record, plan, instruct, inform and train; (5) review.

Fire triangle / tetrahedron: fuel, oxygen, heat and (for combustion chain) the uninhibited chemical chain reaction - extinguishing agents act by removing one or more of these.

Ignition source audit: fixed electrical installations, portable appliance testing, hot work permits, smoking controls, cooking equipment, heating appliances, process heat, static discharge, and machinery friction/sparks.

Fuel load management: minimise stored combustibles, segregate flammables in fire-resisting stores, control waste accumulation, use flame-retardant furnishings, and keep escape routes clear of combustible storage.

Likelihood scoring should consider historical incidents, housekeeping standards, presence of arson-attractive materials, security (external waste bins, letterboxes), and the effectiveness of existing controls.

Severity scoring should consider occupant numbers, mobility and familiarity, sleeping risk, time to escape, building height and complexity, and proximity of other occupied buildings or hazardous installations.

Residual risk must be judged against a tolerance threshold; if the residual risk is not acceptable, additional controls are required before work continues, and the decision and rationale must be recorded.

Dynamic assessment: a personal (dynamic) risk assessment at the point of work is required for non-routine tasks such as hot work, and a specific assessment is needed for young persons, pregnant workers and new/inexperienced staff.

Fire prevention prioritises eliminating ignition sources and controlling fuel; fire protection limits the consequences through detection, warning, compartmentation, suppression and escape provision.

Fire extinguisher selection: water (Class A), foam (Class A and B, not on live electrical or cooking oil), CO2 (Class B and electrical, no cooling effect - re-ignition risk), dry powder (multi-purpose but can impair vision and damage equipment), wet chemical (Class F cooking oils).

Detection choice: ionisation smoke detectors respond well to fast-flaming fires; optical detectors suit smouldering fires; heat detectors suit dusty or smoky environments but respond later; aspirating (ASD) systems suit difficult-access or high-airflow spaces.

Alarm system categories (BS 5839): L1 full coverage throughout, L2 coverage in defined areas plus escape routes, L3 escape routes plus rooms opening onto them, L4 escape routes only, L5 specific areas; P categories protect property.

Emergency lighting (BS 5266) is required for escape routes, open areas over 60 m2, and where failure of normal lighting creates danger; it must provide at least 1 lux along escape route centre lines and 0.5 lux in open areas.

Sprinkler systems: wet pipe (fastest, most common), dry pipe (unheated spaces), pre-action (water-sensitive areas such as IT or archives), deluge (high-hazard rapid application); a sprinkler operates individually when its heat-sensitive element fuses, typically 68 degrees C.

Smoke control: natural ventilation (vents, smoke shafts) and mechanical systems (pressurisation of escape stairs, smoke extract) maintain tenability on escape routes; pressurisation must be commissioned and tested to prove pressure differentials.

Explosion prevention: control of flammable vapours, ATEX/DSEAR classification of hazardous zones, ventilation, inerting, and explosion relief or suppression where a flammable atmosphere cannot be excluded.

Passive protection: fire-resisting construction (walls, floors, doors), fire doors kept closed or held open by fail-safe devices linked to the alarm, cavity barriers, and penetration sealing of service risers.

Means of escape principle: escape must be possible in one direction to a place of relative safety, then two directions to a place of ultimate safety (open air or protected route) - travel distances depend on occupancy, use and whether the route is single-direction.

Occupancy capacity: escape routes are sized by width, typically 1 mm per person for level routes and 2 mm per person for stairs (with minimum widths around 750-1000 mm); exit widths must accommodate the total number of occupants likely to be present.

Number of exits: a single exit is only acceptable for small, low-risk, ground-floor premises with limited travel distance and occupant numbers; otherwise at least two independent exits are required.

Protected escape routes must have fire-resisting construction, be kept clear and self-closing fire doors must not be wedged; a protected route should not pass through high fire-risk areas or be used for storage.

Stairs: protected stair enclosures are required where escape relies on them; final exits must open in the direction of travel where large numbers are present, and exits must never be locked without a fail-safe means of opening.

Assembly points must be remote from the building and clear of fire service access; roll call or sweep systems confirm all persons are accounted for, and evacuation times should be measured and recorded at drills.

Phased or progressive evacuation (horizontal evacuation to a compartment, then full evacuation) is used in hospitals, care homes and high-rise buildings; stay-put policies require compartmentation, alarm zoning and resident communication.

Persons at greater risk: mobility, visual or hearing impairment, temporary injury, pregnancy, lone workers and those unfamiliar with the building require personal emergency evacuation plans (PEEPs) and designated assistance.

Fire safety signage (ISO 7010) and emergency lighting must mark escape routes, exits and fire-fighting equipment; signage must be visible under both normal and emergency lighting conditions.