Understanding how fire works tells you how to prevent it and how to fight it. Understanding the law tells you why all this matters and where responsibility sits.

The fire triangle

Fire needs three things to start and to keep going:

• Fuel — anything that will burn: paper, fabric, wood, plastics, fats, gases
• Heat — an ignition source: flame, spark, friction, hot surface, electrical arc
• Oxygen — the air around us is 21% oxygen, more than enough

Remove any one of the three and the fire goes out. Fire fighting is essentially about removing one or more sides of the triangle — water cools (removes heat), CO2 displaces oxygen, fire blankets smother. Prevention is about keeping the three apart.

The fire tetrahedron

Modern understanding adds a fourth element — the chemical chain reaction. This explains why some specialist extinguishers (e.g. dry powder) interrupt the burning process at a molecular level rather than just removing heat or oxygen.

How fires spread

• Conduction — through solid materials (e.g. a metal pipe heating up across a room)
• Convection — hot gases rise, spreading fire upwards and along ceilings
• Radiation — heat radiating across a space, igniting materials at a distance
• Direct burning — flame contact with combustible material

The dangers of fire

Most deaths in fires are not from the flames. They are from:

• Smoke — thick, hot, often pitch black. Disorients, blinds, and can fill a room in seconds
• Toxic gases — carbon monoxide is the biggest killer. Hydrogen cyanide from burning plastics is rapidly fatal. A few breaths can be incapacitating
• Oxygen depletion — fires use oxygen, leaving less for breathing
• Heat — air at 150°C scorches the airways
• Structural collapse — in advanced fires

This is why evacuation, not firefighting, is the right response in most cases.

The Regulatory Reform (Fire Safety) Order 2005

The principal fire safety law for non-domestic premises in England and Wales (similar legislation in Scotland and Northern Ireland). It applies to virtually every workplace and care setting.

Key duties of the Responsible Person

• Carry out and review a fire risk assessment
• Identify general fire precautions needed
• Eliminate or reduce risk so far as is reasonably practicable
• Provide and maintain fire safety equipment
• Provide fire safety training to staff
• Plan and practise emergency procedures
• Make special provision for people with disabilities or other vulnerabilities
• Provide information to staff, families, contractors

The fire risk assessment

HSE/HM Government 5-step approach:

1. Identify fire hazards (sources of ignition, fuel, oxygen)
2. Identify people at risk (staff, residents, visitors, vulnerable groups)
3. Evaluate, remove, reduce and protect from risk
4. Record findings, prepare an emergency plan, provide training
5. Review and update

The Building Safety Act 2022 and the Fire Safety Act 2021

Following Grenfell, new legislation has tightened obligations especially for higher-risk residential buildings. The Fire Safety Act 2021 clarifies that external walls and fire doors in flats are within the scope of the Fire Safety Order. The Building Safety Act 2022 introduced new regulators and duties for higher-risk buildings.

Enforcement

Local fire and rescue authorities (the Fire Service) enforce the Order. They can issue informal notices, formal enforcement notices, prohibition notices preventing use of the premises, and prosecute. Penalties include unlimited fines and, in the most serious cases, imprisonment. Insurance cover may be void if fire safety has been neglected.

A fire that does not start cannot kill. Prevention is the most important fire safety work. When prevention fails, early detection saves lives.

Common causes of workplace fires

• Electrical faults — overheating equipment, damaged cables, overloaded sockets
• Cooking and catering — unattended pans, hot fats, blocked extracts
• Smoking materials — including in vehicles and outside locations
• Heaters — especially portable, close to combustibles
• Arson — particularly in vulnerable, public-access or boundary-fence locations
• Hot work — welding, grinding, soldering, roofing
• Faulty appliances — especially fridges, freezers, washing machines, tumble dryers
• Lithium-ion battery fires — e-bikes, e-scooters, vapes — an increasing cause

Prevention — housekeeping

• Keep escape routes clear — no stored items, no propped-open fire doors
• Combustible waste removed regularly — not allowed to build up
• Bins located away from buildings, lockable where arson risk exists
• Storage of flammables in fire-resistant cabinets, away from ignition sources
• Smoking only in designated areas with metal bins for cigarette disposal

Prevention — electrical

• PAT (Portable Appliance Testing) on a regular schedule
• Fixed installation inspected (EICR) at least every 5 years for most workplaces
• Do not overload sockets — no daisy-chained extension leads
• Reports of overheating, sparks, smell of burning — act immediately
• Equipment switched off at end of day where not needed
• Chargers and battery devices on hard surfaces, not on beds or fabric

Prevention — kitchens

• Never leave pans unattended
• Keep tea towels and packaging clear of the hob
• Extract hoods cleaned regularly — grease build-up is a major fire risk
• Fire blanket and appropriate extinguisher nearby
• Never put water on a hot fat fire

Lithium-ion batteries — new risk

E-bikes, e-scooters, mobility scooters, laptops, phones, vapes — all contain lithium-ion batteries that can fail catastrophically. Once they start to burn, they are extremely difficult to extinguish, produce huge amounts of toxic smoke, and can reignite hours later.

• Only buy from reputable suppliers
• Charge on non-combustible surfaces, not on beds or in escape routes
• Do not charge overnight unattended
• Do not block hallways with charging e-bikes or scooters
• If a battery is bulging, smoking or hot — evacuate immediately, do not try to fight it

Fire detection — alarms

Most workplaces have an automatic fire detection and alarm system. Types of detector:

• Smoke detectors — optical (good for slow smouldering fires), ionisation (good for fast flaming fires)
• Heat detectors — for kitchens and dusty environments where smoke detectors would false-alarm
• Combined detectors — multi-sensor
• Aspirating systems — very early detection, used in computer rooms and protected areas

Manual call points

The red “break glass” boxes. Anyone discovering a fire should activate the nearest one before evacuating. Located on escape routes, near exits.

Fire alarm panels

The main control panel shows where a fire is detected. Knowing where the panel is and how to silence it (after fire and rescue have authorised) is part of the Fire Marshal role.

Emergency lighting

Battery-backed lights that come on if mains power fails. Mandatory on escape routes and at exits. Tested monthly and annually. If a light is not working, report it.

Fire signage

• Green “running man” signs — exit and direction indicators
• Red signs — fire fighting equipment location, manual call points
• Yellow signs — hazards (e.g. flammable substance store)
• Blue signs — mandatory actions (e.g. fire door keep shut)

Fire doors

Fire doors are not just doors. They are engineered fire barriers that hold back fire and smoke for 30 or 60 minutes (FD30 / FD60). A propped-open fire door provides zero protection.

• Never wedge fire doors open — this is a serious offence
• Hold-open devices linked to the fire alarm (Dorgards or magnetic holders) ARE acceptable
• Damaged fire doors must be repaired — intumescent strips, smoke seals, closer mechanisms all important
• Check fire doors close fully and latch — standard care home and workplace audit item

When the alarm sounds, evacuation is the priority. Practised, well-planned evacuation saves lives. Improvised evacuation costs them.

If you discover a fire

1. Raise the alarm — activate the nearest manual call point
2. Alert anyone in immediate danger
3. Evacuate via the nearest safe exit
4. Close doors behind you to contain the fire
5. Do NOT use lifts (unless an evacuation lift specifically designed for the purpose)
6. Do NOT collect personal belongings
7. Call 999 from outside
8. Go to the assembly point
9. Wait for the all-clear from the Fire Service — do NOT re-enter the building

If you hear the alarm but did not see the fire

1. Stop what you are doing
2. Help anyone with you towards the nearest exit
3. Use the nearest safe exit — not necessarily the main entrance
4. Close doors behind you
5. Assembly point, register check, await all-clear

Fighting the fire — the careful exception

Only attempt to fight a fire if ALL of the following apply:

• You have been trained in the use of extinguishers
• The fire is very small — smaller than a wastebasket fire
• You have the right extinguisher for the fire type
• The alarm has been raised
• You have a clear safe exit behind you
• You are confident, not heroic — this is not the time for bravery

If any of these are not true, evacuate.

Stay-put policies

Some buildings — particularly purpose-built blocks of flats with effective compartmentation — have a stay-put policy: stay in your flat unless the fire is in your flat or affecting your escape route. After Grenfell, stay-put policies are being reassessed in some buildings. Always follow the policy for your specific building, and know if it has changed.

Progressive horizontal evacuation

In some care settings — particularly hospitals, care homes, complex buildings — full evacuation is dangerous (moving very ill people in pyjamas through smoke and cold). The strategy may be progressive horizontal evacuation:

• People in the fire zone moved to the next fire compartment
• Then, if needed, further away
• Full evacuation only if absolutely necessary
• Relies on robust compartmentation (fire-resistant walls and doors)

Staff in such settings need specific training in this approach.

Personal Emergency Evacuation Plans (PEEPs)

For people who cannot evacuate themselves or who need specific support, a PEEP sets out how they will get out safely.

Who needs a PEEP?

• Wheelchair users and people with mobility impairments
• People with visual or hearing impairments
• People with cognitive impairment, dementia, learning disability who would not understand the alarm
• Pregnant employees in late pregnancy
• People with temporary impairments (e.g. broken leg)
• Care home residents — usually a PEEP for every resident

What goes in a PEEP

• The person’s name and where they spend their time
• The specific impairment or need
• Designated buddies / responders
• Evacuation route and equipment (evac chair, ski-pad, ramps)
• Refuge points if relevant — protected spaces near stairs where someone can wait safely for fire service rescue
• Communication aids needed
• Any specific instructions — e.g. medication that must come too, distress responses

PEEPs must be reviewed regularly and practised in drills. A PEEP that lives in a folder and has never been tested is worthless.

Evacuation equipment

• Evac chairs — specialist chairs designed for taking people down stairs
• Ski pads / evacuation mattresses — for bedbound residents, allow safe sliding down stairs
• Refuge points — protected spaces with two-way communication to the fire service

Staff must be trained on the specific equipment in their building.

Roll call and assembly

• The assembly point is a known safe location well clear of the building
• The Fire Marshal or person in charge checks everyone is out
• Visitors should be signed in so they can be accounted for
• If someone is missing or unaccounted for, the Fire Service is told immediately on arrival
• Stay at the assembly point until told otherwise — even if cold and irritated

Fire drills

• At least annually, ideally more often, especially in care
• Different scenarios — not always the same starting point
• Different times of day — night drills matter for residential settings
• Observed, recorded, learned from
• Failures (people taking too long, doors found wedged, PEEPs not followed) are gold dust — the point of a drill is to find them before a real fire does

Each fire extinguisher is designed for a specific class of fire. Using the wrong type can be ineffective or dangerous. The basics matter.

Classes of fire

• Class A — ordinary combustible solids: wood, paper, fabric, plastic
• Class B — flammable liquids: petrol, paint, oils (not cooking oils)
• Class C — flammable gases: propane, butane, natural gas
• Class D — combustible metals: magnesium, lithium, sodium
• Class F — cooking oils and fats (deep fat fryers)
• Electrical fires — not given a letter; involve live electrical equipment

Extinguisher types (UK)

Water (red label)

• For Class A only
• Most common in workplaces — paper, wood, fabric
• NEVER use on electrical fires, fat fires, or flammable liquids

Water with additive / Water mist

• Class A and sometimes Class B or electrical (check label)
• Water mist creates fine droplets that absorb heat and cool rapidly
• Modern, increasingly used in offices, healthcare, and even small kitchens

Foam (cream label)

• Class A and B
• Forms a foam blanket suffocating the fire
• Not for fats or live electrical equipment (unless dielectric tested)

CO2 (black label)

• Class B and electrical fires
• No residue — safer for IT equipment and machinery
• Discharge is very cold — do not hold the horn directly, can cause cold burns
• Less effective outdoors and in windy conditions

Dry powder (blue label)

• Class A, B, C and electrical
• Versatile but very messy — powder gets everywhere and is corrosive to electronics
• Reduces visibility dramatically — not ideal indoors
• Specialist powders for Class D metal fires

Wet chemical (yellow label)

• Class F — cooking oils and fats
• Essential in commercial kitchens
• Creates a soapy layer that smothers and cools the fat

Fire blankets

• For small fires — chip pans, small clothing fires
• Smothers by removing oxygen
• Pull tabs, hold corners away from you, lay over the fire — do not throw
• Leave in place until cool

PASS — how to use an extinguisher

1. Pull the pin
2. Aim at the base of the fire
3. Squeeze the trigger
4. Sweep side to side

Keep low. Test the extinguisher briefly first. Be ready to leave. Most workplace extinguishers discharge in 10-20 seconds — very fast.

What NOT to do

• NEVER put water on a fat fire — the water flashes to steam, throwing burning fat across the kitchen
• NEVER use water or foam on live electrical equipment unless dielectric tested
• NEVER turn your back on the fire
• NEVER continue if smoke is overcoming you or the fire is growing
• NEVER use an extinguisher in a way that blocks your own escape route

After use

• Even a partly-used extinguisher must be reported and refilled / replaced — it is no longer full and reliable
• Tell the Fire Marshal and Responsible Person
• Service annually by a competent person under BS 5306

Designated Fire Marshals (also called Fire Wardens) are appointed by the employer to take specific action in the event of a fire and to support fire safety day-to-day. This is a defined role with clear duties.

Who can be a Fire Marshal?

• A competent person designated by the Responsible Person
• Trained to a recognised standard — this course covers the theory; practical sign-off and in-building training complete it
• Familiar with the specific building, alarm system and procedures
• Physically able to carry out the role (or paired with someone who is)
• Confident and calm

Day-to-day duties

• Walk-rounds — checking fire doors are closed, escape routes clear, signage in place, extinguishers in position
• Notice and report defects — emergency lights, alarm system, missing extinguishers
• Support fire risk assessments and reviews
• Brief new starters on fire procedures for their area
• Support visitor sign-in so everyone is accounted for in an emergency
• Lead by example — never prop fire doors, never store items in escape routes

In the event of a fire — Fire Marshal actions

1. Ensure the alarm is raised
2. Direct evacuation — calmly, clearly, towards the nearest safe exit
3. Sweep designated areas — check toilets, side rooms, quiet spaces where someone might not have heard the alarm
4. Close doors and windows on the way out where safe to do so
5. Support people with PEEPs — their designated buddy(ies) act
6. Account for everyone at the assembly point
7. Inform the Fire Service of anyone missing or unaccounted for on arrival
8. Hand over to the Fire Service when they arrive
9. Prevent re-entry until the all-clear

Sweeping a building

Search areas you are designated for, in a structured way:

• Move quickly, but methodically
• Check toilets, store rooms, meeting rooms, kitchenettes
• Listen and look for anyone in difficulty
• Close doors behind you
• Mark or report what you have cleared
• Never enter smoke-filled areas — your safety comes first

Communication during an emergency

• Speak calmly and clearly
• Use plain language — not technical jargon
• Direct people firmly to the nearest safe exit
• Identify yourself if needed — high-vis vests are common for Fire Marshals
• Reassure people — panic spreads if you panic

Working with vulnerable people

• Know who needs help in your area
• Use PEEPs — follow them as written
• Allocate enough staff to assist — usually one Fire Marshal cannot also evacuate two wheelchair users alone
• Refuge points — for people who cannot use stairs, refuge points are protected spaces where they wait for Fire Service rescue. They are not abandoned — the Fire Marshal stays with them or returns to the location and informs the Fire Service

Record-keeping

• Fire log book — central record of training, drills, alarm tests, maintenance, false alarms, near-misses
• Weekly alarm test (by activating one call point in rotation)
• Monthly checks — emergency lights, extinguisher visible and not used, fire doors operating
• Six-monthly to annual servicing by a competent contractor
• Fire drills recorded with date, time, who participated, time to evacuate, issues identified

After an incident

• Cooperate with the Fire Service investigation
• Internal debrief — what worked, what did not
• Update fire risk assessment if needed
• Address any failings — equipment, training, procedures
• Support staff — even an evacuation without fire is stressful, and a real fire is traumatic

Limits of the role

A Fire Marshal is not a firefighter. The role is about preparation, prevention, evacuation and accountability — not about fighting fires beyond the smallest of incipient stages with appropriate equipment. The Fire Service is the only competent agency for serious fires.

Three short cases from real settings. Read, decide, then check against the model response.