DCP (dry chemical powder) extinguishers cover Class A, B and C fires and suit general workplaces. CO2 extinguishers cover Class B and electrical fires and leave no residue — essential for server rooms and kitchens. Foam covers Class A and B. Most South African workplaces need a combination of DCP and CO2.
Choosing the wrong fire extinguisher for a fire class doesn’t just fail to put the fire out — it can make the fire worse. The Occupational Health and Safety Act and South African fire by-laws require employers to supply appropriate fire extinguishers, not just any extinguisher.
Here is a straightforward guide to the three main fire extinguisher types used in South African workplaces, which fire classes each covers, and where each one belongs.
Fire Classes in South Africa
South Africa uses the European fire classification system:
| Class | Type of Fire |
|---|---|
| Class A | Ordinary combustibles: wood, paper, textiles, plastics |
| Class B | Flammable liquids: petrol, diesel, oils, solvents |
| Class C | Flammable gases |
| Class E | Electrical equipment (not a separate class — a characteristic of the environment) |
| Class F | Cooking oils and fats |
Most workplaces face Class A risks (general combustibles). Workplaces with vehicles, fuel storage, kitchens, or electrical equipment face additional fire classes.
At a Glance: DCP vs CO2 vs Foam
| Extinguisher | Colour Code | Fire Classes Covered | Best Environments | Not Suitable For |
|---|---|---|---|---|
| DCP (Dry Chemical Powder) | Red body, white band | A, B, C | General offices, warehouses, vehicles, construction | Server rooms, fryer kitchens |
| CO2 (Carbon Dioxide) | Red body, black band | B, Electrical (E) | Server rooms, switchboards, commercial kitchens | Large Class A fires, outdoors |
| Foam (AFFF) | Red body, cream/yellow band | A, B | Fuel storage, petrol stations, mixed A/B risk areas | Electrical environments, sub-zero conditions |
DCP — Dry Chemical Powder Extinguisher
Colour code: Red body with white band
Covers: Class A, B and C fires
Sizes available: 1kg, 2.5kg, 4.5kg, 9kg
DCP extinguishers use a dry chemical powder — typically monoammonium phosphate — that smothers flames by interrupting the chemical chain reaction of combustion. They are the most versatile extinguisher type, covering three fire classes.
Best for:
- General office and warehouse environments
- Vehicles and vehicle workshops
- Construction sites
- Any area with mixed fuel types
Not ideal for:
- Server rooms and electrical equipment rooms — the powder is corrosive and ruins electronics
- Kitchens with cooking oil fryers (Class F fires) — DCP does not effectively suppress oil fires
Key fact: DCP extinguishers require an annual service and pressure check. The pressure gauge must be in the green zone. A deflated DCP is a common OHS Act non-compliance finding.
CO2 — Carbon Dioxide Extinguisher
Colour code: Red body with black band
Covers: Class B fires and electrical (Class E) environments
Sizes available: 2kg, 5kg
CO2 extinguishers work by displacing oxygen around the fire, suffocating the flame. They leave no residue — no powder, no foam, no chemical spray. This makes them the only practical choice for environments with sensitive equipment.
Best for:
- Server rooms and data centres
- Switchboard rooms and electrical panels
- Commercial kitchens (equipment areas, not fryer fires)
- Areas where DCP residue would cause significant secondary damage
Not ideal for:
- Class A fires involving large volumes of ordinary combustibles — CO2 is effective but not optimal for deep-seated fires
- Outdoor environments — wind dissipates CO2 before it can suppress the fire
Key fact: CO2 extinguishers have no pressure gauge — pressure is verified by weight during annual servicing. A CO2 that has not been weighed and tagged in the past 12 months is not compliant.
Foam — AFFF Extinguisher
Colour code: Red body with cream/yellow band
Covers: Class A and Class B fires
Sizes available: 6 litre, 9 litre
AFFF (Aqueous Film-Forming Foam) extinguishers work by forming a film over the surface of a liquid fire, cutting off oxygen and preventing re-ignition. They also work on Class A fires by cooling and soaking the material.
Best for:
- Fuel storage areas
- Petrol stations and vehicle workshops
- Areas with both Class A and Class B risks where a single extinguisher type is preferred
Not ideal for:
- Electrical environments — AFFF conducts electricity and creates an electrocution risk
- Cold environments — foam can freeze in sub-zero conditions
What Does the OHS Act Require?
The OHS Act General Safety Regulations do not specify a particular extinguisher type for every workplace — they require employers to conduct a fire risk assessment and provide appropriate extinguishers for the fire risks identified.
In practice, the local fire by-laws (enforced by the local municipality) are more specific. Most South African municipal by-laws require:
- At least one extinguisher per 200–300 m² of floor area
- Extinguishers no more than 30 metres from any point in the building
- Annual servicing by a registered service provider
Which Combination Does Your Workplace Need?
| Workplace Type | Recommended Combination |
|---|---|
| General office | DCP (general areas) + CO2 (server/IT rooms) |
| Warehouse | DCP (all areas) |
| Restaurant / kitchen | DCP (general) + CO2 (equipment) + Wet Chemical (fryer area) |
| Workshop / garage | DCP + Foam |
| Server room / data centre | CO2 only |
| Construction site | DCP |
| Student accommodation | DCP (general) + CO2 (kitchen equipment areas) |
Frequently Asked Questions
What is the most common fire extinguisher in South African workplaces?▼
DCP (dry chemical powder) is the most common because it covers Class A, B, and C fires and suits general workplaces. Most businesses need at least one DCP, often paired with a CO2 for server rooms or electrical areas.
Does a small office need a CO2 extinguisher?▼
If your office has a server room, IT room, or any area with sensitive electronic equipment, yes. CO2 is the only practical extinguisher type for those areas because it leaves no residue that would damage equipment. A general office without dedicated IT infrastructure can typically be covered by DCP alone.
How many fire extinguishers does the OHS Act require?▼
The OHS Act General Safety Regulations do not specify an exact number — they require extinguishers appropriate to the fire risk. Local municipal by-laws typically require at least one extinguisher per 200–300 m² of floor area, with no point in the building more than 30 metres from an extinguisher.
How often must fire extinguishers be serviced in South Africa?▼
South African fire by-laws require annual servicing by a registered service provider. The service must be documented on a tag attached to the extinguisher. A CO2 extinguisher without a current weight certificate is non-compliant and will be flagged in any OHS Act inspection.
Can I use a DCP extinguisher on an electrical fire?▼
DCP can be used near electrical equipment in an emergency, but it is not ideal. The powder is corrosive and will damage electronics. CO2 is the correct choice for electrical fires — it suppresses without residue and is safe to use on live electrical equipment.
What fire extinguisher does a restaurant kitchen need?▼
A commercial kitchen typically needs three types: DCP for general areas, CO2 for cooking equipment and electrical boards, and a wet chemical (Class F) extinguisher for fryer and cooking oil fires. DCP must not be used on Class F fires.
What is the difference between a 4.5kg and a 9kg DCP extinguisher?▼
The 4.5kg is suitable for smaller areas and vehicles. The 9kg provides greater discharge duration and coverage — typically used in warehouses, large offices, and industrial areas. Choose based on the fire risk assessment for each area of your workplace.
Where to Buy Fire Extinguishers in South Africa
Dimple Safety stocks DCP, CO2 and foam fire extinguishers from our Booysens, Johannesburg warehouse, along with fire blankets and fire equipment signage.
All extinguishers are available for same-day collection or delivery. We can assist with fire compliance packages for workplaces, student accommodation, and industrial sites.
📞 011 493 3000 | 🌐 dimplesafety.co.za | 📍 Booysens, Johannesburg
