49 CFR §393.95: Emergency Equipment Regulation
Federal regulation text for fire extinguisher and emergency equipment on CMVs
Last updated: March 11, 2026
Contents
Overview
49 CFR §393.95 establishes federal requirements for emergency equipment on all power units operating in interstate commerce. These regulations ensure commercial motor vehicles carry appropriate fire suppression equipment for emergency situations.
The regulation applies to all commercial motor vehicles including trucks, truck tractors, and buses, with specific requirements based on the type of cargo being transported. Compliance is enforced by the Federal Motor Carrier Safety Administration (FMCSA). Fire extinguishers must meet UL 299 and UL 711 standards for certification.
The full regulation text is published in Title 49, Part 393, Subpart H of the Electronic Code of Federal Regulations.
Looking for product recommendations? Our DOT fire extinguisher buying guide matches specific extinguisher models to each vehicle type — semi-trucks, box trucks, tankers, buses, and pickups — with specs, pricing, and add-to-cart.
Quick Reference
Minimum fire extinguisher requirements by vehicle and cargo type under 49 CFR §393.95.
| Vehicle / Cargo Type | Min. UL Rating | Qty | Allowed Agent Types |
|---|---|---|---|
| Standard CMV | 5 B:C | 1 | Dry chemical, CO₂, halogenated |
| Standard CMV (alternate) | 4 B:C | 2 | Dry chemical, CO₂, halogenated |
| Hazmat (placardable quantities) | 10 B:C | 1 | Dry chemical, CO₂, halogenated |
| Compressed gas fuel vehicle | 5 B:C | 1 | Dry chemical, CO₂, halogenated |
Standard CMV
Rating: 5 B:C · Qty: 1
Agents: Dry chemical, CO₂, halogenated
Standard CMV (alternate)
Rating: 4 B:C · Qty: 2
Agents: Dry chemical, CO₂, halogenated
Hazmat (placardable)
Rating: 10 B:C · Qty: 1
Agents: Dry chemical, CO₂, halogenated
Compressed gas fuel
Rating: 5 B:C · Qty: 1
Agents: Dry chemical, CO₂, halogenated
Water-based extinguishers are prohibited on all CMVs due to freezing concerns. ABC-rated dry chemical extinguishers satisfy both B:C requirements and provide additional Class A coverage for ordinary combustibles.
Vehicle Requirements
Standard commercial vehicles not transporting hazardous materials must carry:
- Option A: One fire extinguisher with an Underwriters' Laboratories rating of 5 B:C or more
- Option B: Two fire extinguishers, each with an Underwriters' Laboratories rating of 4 B:C or more
- Class A rating is not required but may be beneficial for cargo fires
- Dry chemical, carbon dioxide, or halogenated agent types are acceptable
- Water-based extinguishers are prohibited due to freezing concerns
Most carriers choose ABC-rated dry chemical extinguishers because they cover Class A (ordinary combustibles like wood, paper, rubber), Class B (flammable liquids), and Class C (electrical fires) in a single unit. A 5 lb ABC extinguisher typically carries a 3-A:40-B:C rating, which exceeds the minimum 5 B:C requirement.
Note: Many carriers require higher ratings or additional extinguishers based on their safety policies.
Hazmat Transport Requirements
Vehicles transporting hazardous materials in placardable quantities must carry a higher-rated extinguisher. Placarding is generally required when shipping 1,001 lbs or more of a hazmat class, or any quantity of certain high-hazard materials (49 CFR §172.504).
- Minimum Rating: One extinguisher with UL rating of 10 B:C or more
- Division 1.1, 1.2, 1.3 Explosives: No open flame warning devices permitted
- Class 3 Flammable Liquids: Additional restrictions on ignition sources
- Division 2.1 Flammable Gases: Special mounting requirements away from relief valves
- Compressed Gas Fuel Vehicles: Extinguisher required regardless of cargo
A 10 lb ABC dry chemical extinguisher (typically rated 4-A:80-B:C) is the most common choice for hazmat transport because it exceeds the 10 B:C minimum and provides Class A coverage.
Specifications & Mounting
DOT requirements for extinguisher installation:
- UL Rating Label: Must be clearly marked by manufacturer with UL rating
- Visual Indicator: Must permit visual determination of charge status
- Accessibility: Must be readily accessible for immediate use
- Secure Mounting: Must be mounted to prevent sliding, rolling, or vertical movement
- Weather Protection: Extinguishing agent must not require freeze protection
- Location: Typically mounted in cab, but may be outside if weather-protected
- EPA Compliance: Agents must meet SNAP regulations for environmental safety
Selecting a Compliant Extinguisher
The regulation specifies minimum UL ratings and allowed agent types (dry chemical, CO₂, halogenated) but does not mandate a specific product. ABC-rated dry chemical extinguishers are the most common choice because they satisfy both the B:C requirement and provide additional Class A coverage.
Need help choosing? Our vehicle-by-vehicle product guide matches specific extinguisher sizes and models to each commercial vehicle type — semi-trucks, box trucks, tankers, buses, and pickups — with specs and pricing.
Inspection & Maintenance
Required inspection and maintenance procedures follow NFPA 10 standards for portable fire extinguishers:
Monthly Visual Inspection:
- Verify extinguisher is in designated location
- Check for physical damage or corrosion
- Confirm pressure gauge shows full charge
- Ensure mounting bracket is secure
Annual Service:
- Professional inspection by certified technician
- Weight check for agent loss
- Verification of discharge components
- Update of inspection tag
- Documentation: Maintain records of inspections and service
- Replacement: Immediate replacement if discharged or damaged
- Hydrostatic Testing: Required at intervals per manufacturer specifications
Common DOT Violations & Penalties
Fire extinguisher violations are among the most common findings during FMCSA roadside inspections. These fall under the Vehicle Maintenance BASIC in the Compliance, Safety, Accountability (CSA) program and can result in out-of-service orders.
- Missing or expired extinguisher: The most common violation. No extinguisher on board, or the inspection tag shows the unit is past due for annual service. Results in an out-of-service violation.
- Incorrect UL rating for cargo type: Carrying a 5 B:C unit while transporting placardable hazmat (which requires 10 B:C). The vehicle is placed out of service until the correct extinguisher is provided.
- Improper mounting: Extinguisher not secured, sliding or rolling loose in the cab or on the frame. This violates the secure mounting requirement and is citable even if the extinguisher itself is compliant.
- Blocked access: Extinguisher buried under cargo, tools, or personal items and not readily accessible for immediate use.
- No pressure gauge or unreadable label: The charge indicator must be visible, and the UL rating label must be legible. Faded, painted-over, or missing labels are violations.
- Wrong agent type: Water-based extinguishers are prohibited on CMVs. Only dry chemical, CO₂, and halogenated agents are allowed.
FMCSA penalties for fire extinguisher violations include out-of-service orders (the vehicle cannot move until the deficiency is corrected), CSA points against the carrier's Vehicle Maintenance BASIC score, and fines up to $16,000 per violation. Repeated violations can trigger a compliance investigation of the carrier.
Frequently Asked Questions
What size fire extinguisher is required for a commercial truck?
A standard commercial truck (not hauling hazmat) needs at least one fire extinguisher rated 5 B:C or higher, or two extinguishers each rated 4 B:C or higher. A 5 lb ABC dry chemical extinguisher (typically rated 3-A:40-B:C) is the most common choice and exceeds the minimum requirement.
Do I need a fire extinguisher in my pickup truck?
Only if the pickup is operating as a commercial motor vehicle (CMV) in interstate commerce — generally vehicles with a GVWR over 10,001 lbs, or those transporting hazardous materials in placardable quantities. Personal pickup trucks not used for commercial purposes are not subject to 49 CFR §393.95.
How often do DOT fire extinguishers need to be inspected?
Monthly visual inspections (check gauge, location, damage) and annual professional servicing by a certified fire extinguisher technician. Drivers should verify the extinguisher during pre-trip inspections. Hydrostatic testing is required per the manufacturer's schedule, typically every 6 or 12 years depending on the cylinder type.
What type of fire extinguisher is required for hazmat transport?
Vehicles hauling hazardous materials in placardable quantities must carry at least one extinguisher rated 10 B:C or higher. A 10 lb ABC dry chemical extinguisher is recommended because it exceeds the 10 B:C minimum and provides Class A coverage. CO₂ and halogenated agents are also permitted.
Can I use a water fire extinguisher in a commercial vehicle?
No. Water-based extinguishers are prohibited under 49 CFR §393.95 because the agent is subject to freezing. Only dry chemical, carbon dioxide (CO₂), and halogenated agents are allowed on commercial motor vehicles.
Where should a fire extinguisher be mounted in a truck?
The cab is the preferred location for easy access. Outside mounting is acceptable if the extinguisher is weather-protected and the agent does not require freeze protection. The extinguisher must be securely mounted with a bracket to prevent movement, and it must be readily accessible — not buried behind cargo, tools, or equipment.
DOT Compliant Fire Extinguishers
See our vehicle-by-vehicle product guide for DOT-compliant extinguishers with specs, sizing recommendations, and pricing by vehicle type.