Fire
Extinguishers

Portable fire extinguisher selection, siting, maintenance and BS 5306 compliance.

Fire Classes — UK (BS EN 2)

UK fire classification follows BS EN 2:1992. Understanding fire classes is essential for correct extinguisher selection. Using the wrong extinguisher can be ineffective or dangerous.

ClassFuel TypeExamplesSuitable Extinguishers
Class ASolid carbonaceous materialsWood, paper, textiles, plasticsWater, foam, dry powder, wet chemical, CO₂ (limited)
Class BFlammable liquidsPetrol, diesel, oil, paint, solventsFoam, dry powder, CO₂
Class CFlammable gasesLPG, natural gas, butane, propaneDry powder (shut off supply first)
Class DCombustible metalsMagnesium, titanium, aluminium swarfSpecialist dry powder (L2, M28, Met-L-X)
ElectricalElectrical equipment (not a formal class)Computers, switchgear, motorsCO₂, dry powder, water mist (dielectrically tested)
Class FCooking oils and fatsDeep fat fryers, cooking oilWet chemical (Class F specific)
Never use water on Class B, C, D, or F fires. Water on burning oil causes a violent steam explosion. Water on electrical equipment creates electrocution risk. Water on metal fires can cause violent reactions.
Extinguisher Types & Colour Codes

All UK fire extinguishers are red (BS EN 3). A coloured band (approximately 5% of the body area) identifies the agent type. The coloured band is typically a panel or label on the upper body of the extinguisher.

Water
Class A only
Red body, red label. Cools burning material. Most effective on Class A fires. Do NOT use on electrical, liquid, or cooking oil fires.
Foam (AFFF)
Class A & B
Red body, cream/beige label. Smothers and cools. Effective on Class A and B. Do NOT use on electrical fires or cooking oil.
CO₂
Class B & Electrical
Red body, black label. Displaces oxygen. Safe on electrical equipment. Limited effectiveness on Class A. No residue.
Dry Powder (ABC)
Class A, B & C
Red body, blue label. Multi-purpose. Effective on A, B, C fires. Leaves residue. Not recommended for enclosed spaces or sensitive equipment.
Wet Chemical
Class F (also A)
Red body, yellow label. Specifically designed for Class F (cooking oil) fires. Also effective on Class A. Do NOT use on electrical fires.
Water Mist
Class A, B, C, F & Electrical
Red body, white label. Ultrafine water mist. Dielectrically tested — safe on electrical equipment. Effective on multiple fire classes. Premium product.
Extinguisher Selection Guide

Extinguisher selection is governed by BS 5306-8 and the RRFSO 2005. The responsible person must ensure that appropriate extinguishers are provided for the fire risks present. Always conduct a fire risk assessment.

Premises TypeTypical Fire RisksRecommended Extinguishers
OfficeClass A (paper, furniture), electrical equipmentWater or foam (Class A) + CO₂ (electrical)
Kitchen / CanteenClass A, Class F (cooking oil)Wet chemical (Class F) + CO₂ or water (Class A)
Warehouse / StorageClass A (stock, packaging)Water or foam (large capacity)
Garage / WorkshopClass A, Class B (fuel, oil)Foam or dry powder (Class B) + water (Class A)
Server Room / Data CentreElectrical, Class ACO₂ (no residue) — consider gaseous suppression system
RetailClass A, electricalWater or foam + CO₂
Chemical storageClass B, Class CDry powder (ABC) — consult specialist
Metal workingClass DSpecialist Class D dry powder
Minimum Provision (BS 5306-8): A minimum of two extinguishers per floor is recommended, with a minimum aggregate rating of 26A for Class A risks. For Class B risks, a minimum of 12B rating is required. Always refer to the fire risk assessment for specific requirements.
Extinguisher Ratings Explained

UK extinguishers are rated to BS EN 3. The rating indicates the size of fire the extinguisher can extinguish in a standard test. Higher numbers indicate greater fire-fighting capability.

RatingMeaningTypical Product
13AClass A — can extinguish a 13-unit wood crib fireSmall 2 litre water extinguisher
21AClass A — larger fire3 litre water extinguisher
34AClass A — larger fire6 litre water extinguisher
55AClass A — large fire9 litre water extinguisher
21BClass B — can extinguish a 21-litre fuel fire2 kg CO₂ extinguisher
55BClass B — larger fuel fire2 kg dry powder extinguisher
113BClass B — large fuel fire6 kg dry powder extinguisher
How to Use a Fire Extinguisher — PASS Technique

The PASS technique is the standard method for operating a portable fire extinguisher. It applies to all types of extinguisher.

  1. Pull — Pull the safety pin from the handle. This breaks the tamper seal and allows the handle to be pressed.
  2. Aim — Aim the nozzle or horn at the base of the fire, not the flames. Getting to the base of the fire is key.
  3. Squeeze — Squeeze the handle to discharge the extinguishing agent. Release to stop discharge.
  4. Sweep — Sweep the nozzle from side to side across the base of the fire until it is extinguished.
Only attempt to fight a fire if: The fire is small and contained. You have a clear escape route behind you. You have been trained in extinguisher use. You are not at personal risk. If in doubt, evacuate immediately and call 999.
BS 5306 — Maintenance Requirements

BS 5306-3 specifies the maintenance requirements for portable fire extinguishers. Maintenance must be carried out by a competent person (typically a BAFE-registered engineer). The responsible person must ensure that extinguishers are maintained in accordance with BS 5306-3.

Service TypeFrequencyWhoWhat is Checked
Basic ServiceAnnualCompetent person (BAFE registered)Visual inspection, pressure check, weight check, pin and tamper seal, label, location. Discharge and refill if required.
Extended ServiceEvery 5 years (water/foam/wet chemical) or 10 years (CO₂/dry powder)Competent personFull discharge, internal inspection, hydraulic pressure test of cylinder, refill, recharge.
Overhaul / ReplacementPer manufacturer recommendation or BS 5306-3 tableCompetent personFull strip-down, inspection, replacement of worn parts, recharge.
Service Life — Extinguisher Types
TypeBasic ServiceExtended ServiceReplacement
Water / Foam / Wet ChemicalAnnualEvery 5 yearsAfter 25 years (or per manufacturer)
CO₂Annual (weight check)Every 10 years (hydraulic test)After 10 years (or per manufacturer)
Dry Powder (stored pressure)AnnualEvery 5 yearsAfter 25 years (or per manufacturer)
Dry Powder (cartridge)AnnualEvery 5 yearsAfter 25 years (or per manufacturer)
CO₂ Cylinders: CO₂ extinguishers must be weighed annually to check for leakage. A loss of more than 10% of the charge weight requires recharging. CO₂ cylinders must be hydraulically tested every 10 years.
Siting and Positioning (BS 5306-8)
RequirementDetail
Maximum travel distance (Class A)30m to the nearest appropriate extinguisher
Maximum travel distance (Class B)10m to the nearest appropriate extinguisher
Mounting height (up to 3 kg / 3 L)Handle at 1.0m above finished floor level
Mounting height (over 3 kg / 3 L)Handle at 0.5m above finished floor level
VisibilityExtinguishers must be clearly visible. Use wall bracket or stand. Position near exit routes.
SignageBS 5499-5 pictogram signs required where extinguishers are not immediately visible.
Protection from damageProtect from physical damage, frost, and direct sunlight. Use protective covers where necessary.
GroupingWhere more than one extinguisher is required, group them together at a fire point.
Manufacturers & Products
Kidde (Carrier Fire & Security)

Kidde is one of the world's largest fire protection manufacturers. Their UK range includes portable extinguishers, fire suppression systems, and detection equipment. Kidde extinguishers are widely used in commercial, industrial, and residential applications.

Range
ABC Dry Powder, CO₂, Water, Foam, Wet Chemical
Certification
BS EN 3, BSI Kitemark
Sizes
1 kg to 9 kg (powder), 2 kg to 5 kg (CO₂), 2 L to 9 L (water/foam)
Service
BAFE-registered service network
BS EN 3 BSI Kitemark CE Marked BAFE Approved
Chubb Fire & Security

Chubb is a major UK fire protection brand with a long history in the UK market. Chubb extinguishers are available in all standard types and are widely used in commercial and industrial premises. Chubb also offers service and maintenance contracts through their national engineer network.

Range
ABC Dry Powder, CO₂, Water, Foam, Wet Chemical, Water Mist
Certification
BS EN 3, BSI Kitemark
Service
BAFE-registered service and maintenance
Sizes
1 kg to 9 kg (powder), 2 kg to 5 kg (CO₂), 2 L to 9 L (water/foam)
Firechief Global

Firechief Global is a UK manufacturer and distributor of fire extinguishers and fire safety products. Their Xtra range features a unique stainless steel construction for corrosion resistance, making them suitable for harsh environments including coastal, industrial, and food production facilities.

Xtra Range
Stainless steel body. Corrosion resistant. 5-year guarantee.
Types
Water, Foam, CO₂, Dry Powder, Wet Chemical
Certification
BS EN 3, BSI Kitemark
Sizes
1 kg to 9 kg (powder), 2 kg to 5 kg (CO₂), 2 L to 9 L (water/foam)
Amerex (Specialist / Industrial)

Amerex is a US manufacturer of specialist fire extinguishers, widely used in aviation, marine, and industrial applications. Their Class D extinguishers (for metal fires) and vehicle-mounted extinguishers are particularly well-regarded in the UK specialist market.

Class D
Specialist dry powder for metal fires (Mg, Ti, Al)
Vehicle Mounted
Dry powder and CO₂ for vehicle and plant
Certification
UL Listed, FM Approved
Monthly Inspection Checklist

Monthly visual inspections should be carried out by a responsible person (not necessarily a trained engineer). The following checklist covers the key points. Record all inspections in the fire safety log book.

  1. Check the extinguisher is in its designated location and clearly visible.
  2. Check the pressure gauge (if fitted) is in the green zone.
  3. Check the safety pin is in place and the tamper seal is intact.
  4. Check the extinguisher body for dents, corrosion, or damage.
  5. Check the hose or horn is undamaged and not blocked.
  6. Check the label is legible and the service label is up to date.
  7. Check the extinguisher weight (lift to check — should feel full).
  8. Record the inspection in the fire safety log book with date and signature.
Annual Service: Monthly inspections do not replace the requirement for an annual service by a BAFE-registered engineer. Annual service must be recorded on the service label attached to the extinguisher and in the fire safety log book.