NFPA 10 sets the mounting height of a portable fire extinguisher by its gross weight. A unit of 40 pounds or less is installed with its top no more than 5 feet above the floor. A unit over 40 pounds, other than a wheeled type, is installed with its top no more than 3.5 feet above the floor. A hand portable unit keeps at least 4 inches between its bottom and the floor. OSHA's extinguisher rule gives no mounting height. The ADA Standards limit how far a cabinet can stick out into a hallway and how high its hardware can sit.
Section numbers here are from the 2022 edition of NFPA 10, 29 CFR 1910.157, and the 2010 ADA Standards. NFPA lists 2026 as the current edition of NFPA 10. Check the edition adopted for the project, and confirm with the Authority Having Jurisdiction (AHJ) before you relocate anything.
The requirements at a glance
| Requirement | Limit | Source |
|---|---|---|
| Top of a unit with a gross weight of 40 lb or less | No more than 5 ft (60 in) above the floor | NFPA 10 6.1.3.9.1 |
| Top of a unit over 40 lb gross weight (not wheeled types) | No more than 3.5 ft (42 in) above the floor | NFPA 10 6.1.3.9.2 |
| Bottom of a hand portable unit | At least 4 in above the floor | NFPA 10 6.1.3.9.3 |
| Class A travel distance | 75 ft | NFPA 10 6.2.1.2.2; OSHA 1910.157(d)(2) |
| Basic Class B spill-fire travel distance | 30 ft or 50 ft under NFPA 10, set by the hazard level and the B rating; 50 ft under OSHA | NFPA 10 6.3.1.3 and Table 6.3.1.1; OSHA 1910.157(d)(4) |
| Class D travel distance | 75 ft | NFPA 10 6.5.2; OSHA 1910.157(d)(6) |
| Class K travel distance | 30 ft from the cooking hazard | NFPA 10 6.6.2 |
| Projection into a circulation path | 4 in maximum where the leading edge is more than 27 in and not more than 80 in above the floor | 2010 ADA Standards 307.2 |
| Cabinet hardware within an unobstructed forward or side reach | 15 in to 48 in above the floor | 2010 ADA Standards 308 and 309.3 |
Mounting height under NFPA 10
NFPA 10 measures to the top of the extinguisher and sorts units by gross weight:
- 40 pounds or less: the top is no more than 5 feet (60 inches) above the floor (6.1.3.9.1).
- Over 40 pounds: the top is no more than 3.5 feet (42 inches) above the floor. Wheeled types are excluded (6.1.3.9.2).
- Every hand portable unit: the bottom of the extinguisher is at least 4 inches above the floor (6.1.3.9.3).
Wheeled extinguishers are kept in designated locations instead (6.1.3.5). A cabinet or wall recess is installed so the unit inside still meets the height limits (6.1.3.11.5). NFPA 10 names no preferred height inside those limits, so also check access, mounting hardware, and accessibility requirements.
OSHA's rule has no number for height. 29 CFR 1910.157(c)(1) requires extinguishers to be mounted, located, and identified so employees can reach them readily without risk of injury. OSHA's Evacuation Plans and Procedures eTool gives 5 feet, 3.5 feet, and 4 inches, with the first two measured to the carrying handle. A unit mounted to NFPA 10's top-of-unit rule also sits inside those handle heights.
Travel distance and how many extinguishers
NFPA 10 defines travel distance as the actual walking distance from a point to the nearest extinguisher that meets the hazard requirements (3.3.27). Its Annex E, which is explanatory and adds no requirements, notes that partitions, doorways, aisles, stored material, and machinery all lengthen that walk (E.1.4). Sprinklers or other fixed protection do not reduce the extinguisher requirement (6.1.1.1).
Each room or area is classed as light, ordinary, or extra hazard (5.4.1). The amount of flammable liquid expected in any room or area is part of the test: under 1 gallon for light hazard, 1 to 5 gallons for ordinary, and over 5 gallons for extra (5.4.1.1 to 5.4.1.3).
Class A: travel distance and floor area together
No point on the floor is more than 75 feet of travel from an extinguisher (6.2.1.2.2). Each floor also has at least as many units as its area divided by the area one unit may protect (6.2.1.2.1), and more go in where the travel distance needs them (6.2.1.2.3).
| Hazard level | Smallest single extinguisher | Floor area per unit of A rating |
|---|---|---|
| Light | 2-A | 3,000 sq ft |
| Ordinary | 2-A | 1,500 sq ft |
| Extra | 4-A | 1,000 sq ft |
Those values come from NFPA 10 Table 6.2.1.1, which also caps the area for one extinguisher at 11,250 square feet at every hazard level. A unit covers its A rating times the floor area per unit of A, up to that cap, so a 2-A unit covers 6,000 square feet in light hazard and 3,000 in ordinary hazard (Annex E.3.3). Lower-rated units can be added but generally do not count toward the table (6.2.1.3).
How far apart extinguishers end up
There is no universal spacing between extinguishers. Check the actual walking path from each protected location and the allowable floor area for each extinguisher. Annex E shows where the 11,250-square-foot cap comes from. The largest square with no point more than 75 feet from its center is about 106 feet on a side, and the annex figure places units 106 feet apart on an open, unobstructed floor (E.3.4). Treat that as an illustration for one floor shape. Walls, doors, and racks lengthen the walk.
Class B: distance depends on the rating
For spill fires in flammable liquids, a higher B rating permits a longer travel distance (6.3.1.3 and Table 6.3.1.1):
| Hazard level | Minimum rating within 30 ft | Minimum rating within 50 ft |
|---|---|---|
| Light | 5-B | 10-B |
| Ordinary | 10-B | 20-B |
| Extra | 40-B | 80-B |
Liquids more than 1/4 inch deep are of appreciable depth (3.3.17) and have their own rules. Portable extinguishers cannot be the only protection where the surface exceeds 10 square feet (6.3.2.1). The rating is at least 2 B units per square foot of the largest hazard area (6.3.2.2), and AFFF or FFFP units may use 1 B unit per square foot (6.3.2.3). Travel is no more than 50 feet (6.3.2.6).
Class C and Class D
Extinguishers with a Class C rating are required where energized electrical equipment can be encountered (6.4.1). NFPA 10 sets no Class C distance of its own. The units are sized and located for the Class A or Class B hazard expected (6.4.3). Class D extinguishers or agents go in work areas that generate combustible metal powders, flakes, shavings, chips, or similar products (6.5.3), within 75 feet of travel from the hazard (6.5.2).
Class K in commercial kitchens
Class K extinguishers are required where fires in cooking oils and fats are possible (6.6.1), such as at fryers, griddles, and stove tops (Annex A.6.6.1), within 30 feet of travel from the hazard (6.6.2). An extinguisher provided for appliances that cook with oils and fats is listed and labeled for Class K (5.5.4.5), and one installed for them without a Class K rating is taken out of service (5.5.4.5.2). Where an automatic system also protects the hazard, a placard near the extinguisher tells the user to actuate that system first (5.5.4.5.3).
The kitchen still needs coverage for its other hazards. NFPA 10 calls for Class A extinguishers for building protection and for extinguishers matched to each class of hazard present (5.5.2 and 5.5.3.1). A unit with more than one letter rating counts toward each of its classes (5.5.1), so confirm that the ratings and coverage address every hazard present. The fixed system has its own schedule, covered in kitchen hood suppression inspection requirements.
Visibility, access, and signs
- Extinguishers are placed where they are easy to see, easy to reach, and available at once in a fire (6.1.3.1), along normal paths of travel, including exits from areas (6.1.3.2).
- They are installed where they are visible (6.1.3.3.1). Where a visual obstruction cannot be avoided, signs or other means show the location (6.1.3.3.2). The sign sits close to the extinguisher and can be seen from the normal path of travel (6.1.3.3.4 and 6.1.3.3.5).
- The operating instructions face outward (6.1.3.10.1). Six-year maintenance, hydrostatic test, and HMIS labels stay off the front of the unit (6.1.3.10.2).
- A unit exposed to impact, vibration, or the environment is protected against that damage (6.1.3.8).
None of those sections gives a height or size for the sign. Annex A names a purpose-made extinguisher sign as the main way to mark a location, with arrows, lights, or coding on a wall or column as other means (A.6.1.3.3.2). Check local requirements before you specify a sign height.
Brackets, hangers, and cabinets
Every portable extinguisher other than a wheeled one goes on a hanger intended for that extinguisher, in a bracket with release straps or bands from the extinguisher's manufacturer, in a listed bracket with release straps or bands approved for the purpose, or in an approved cabinet or wall recess (6.1.3.4). Approved means acceptable to the AHJ (3.2.1). Hangers and brackets are not made in the field (6.1.3.4.1). Strap-type brackets are required in two places: in or on a vehicle, an approved strap-type bracket designed for vehicles (6.1.3.6), and where a unit could be knocked loose, an approved strap-type bracket designed to prevent that (6.1.3.7).
Cabinets have rules of their own:
- Cabinets are not locked, except where extinguishers are subject to malicious use and the cabinet has a means of emergency access (6.1.3.11.1.1).
- A cabinet with a break-front panel has a breaker bar or hammer for reaching the extinguisher in a fire (6.1.3.11.1.2).
- An extinguisher can go in a cabinet if it stays visible or signs or other means show where it is (6.1.3.3.3). Cabinet units that cannot be seen from the normal path of travel get signs or other means visible from that path (6.1.3.11.2).
- In a fire resistance-rated wall, only surface-mounted cabinets or listed fire-rated cabinets are installed, though existing installations are exempt (6.1.3.11.6 and 6.1.3.11.6.1).
What the ADA adds
The 2010 ADA Standards have no mounting height for a fire extinguisher, but two general rules shape how extinguishers and cabinets go on a wall.
Protruding objects. An object whose leading edge is more than 27 inches and not more than 80 inches above the floor can protrude no more than 4 inches into a circulation path (307.2). At 27 inches or lower it is within the sweep of a cane and can protrude any amount, though no protruding object can reduce the clear width of an accessible route (307.5). On a hallway that usually means a recessed or semi-recessed cabinet projecting 4 inches or less, or a surface-mounted unit whose bottom edge is 27 inches or less above the floor and still at least 4 inches up for NFPA 10. In a fire resistance-rated wall, the NFPA 10 cabinet rule above limits the recessed options.
Reach range. Operable parts on accessible routes and in accessible rooms and spaces comply with section 309 (205.1). For cabinet hardware:
- The latch or handle sits between 15 and 48 inches above the floor for an unobstructed forward or side reach (308.2.1, 308.3.1, 309.3). Check section 308 for obstructed reaches.
- It works with one hand, without tight grasping, pinching, or twisting of the wrist, and takes no more than 5 pounds of force (309.4), with clear floor space in front (309.2).
- Non-operable cabinet portions may extend outside the reach range. Keep every operable cabinet part within an applicable reach range.
Who enforces each rule
The fire code. NFPA 10 sets minimum requirements for selecting, installing, inspecting, maintaining, recharging, and testing portable extinguishers (1.1 and 1.1.1). The fire code or building code in force decides which buildings need them. The International Fire Code requires installation under its own extinguisher section and NFPA 10, which is how the NFPA 10 numbers become enforceable.
OSHA. 29 CFR 1910.157 applies to extinguishers provided for employee use, and OSHA enforces it against the employer. It has no mounting height and no Class K paragraph. NFPA 10's Class B table limits of 30 and 50 feet do not exceed OSHA's 50-foot Class B travel limit, but selection and the rest of each rule must also be checked. Class D extinguishers are required where combustible metal powders, flakes, or shavings are generated at least once every two weeks. The exemption in 1910.157(b)(1) requires an implemented policy of immediate, total evacuation upon the fire alarm, plans meeting 1910.38 and 1910.39, and no extinguishers available, unless another Part 1910 standard requires one. The fire code still decides whether the building needs extinguishers.
The ADA. The Department of Justice issues the 2010 ADA Standards, which cover new construction and alterations of public accommodations, commercial facilities, and state and local government facilities. A passed fire inspection does not establish ADA compliance.
Placement findings on an extinguisher inspection
NFPA 10's periodic inspection checks, among other items, that each extinguisher is in its designated place, visible or marked, and reachable (7.2.2). In harsher locations, such as those with severe hazards or exposure to damage, it also confirms the nameplate instructions are legible and face outward (7.2.2.3 and 7.2.2.4). Our article on fire extinguisher inspection requirements covers the schedule. Record the location, observed condition, and applicable requirement for each placement finding. Common ones:
- The top of the unit is above the limit for its gross weight, or a hand portable unit sits less than 4 inches off the floor.
- The unit is blocked, or hidden with nothing marking its location.
- A cabinet is locked with no means of emergency access.
- The unit hangs on a field-made hanger or one meant for a different extinguisher.
- A new partition or storage has stretched the walking path past the travel distance.
- A cooking-oil hazard has no Class K unit within 30 feet, or the placard is missing where an automatic system protects it.
Recording placement findings in Inspect Point
Inspect Point keeps extinguisher records by building, alongside the alarm, sprinkler, and fire door records. Custom questions can be added to an inspection, so a contractor can put its own placement checks on the extinguisher form. Technicians annotate photos in the app, deficiency severity options are Non-Critical, Critical, and Impairment, and the report generates on submit. See the extinguisher trade page and the deficiencies page.
Common questions
How high should a fire extinguisher be mounted?
For a unit with a gross weight of 40 pounds or less, the top is no more than 5 feet above the floor. For a heavier unit other than a wheeled type, the top is no more than 3.5 feet above the floor. A hand portable unit keeps at least 4 inches between its bottom and the floor.
What is the OSHA mounting height for a fire extinguisher?
29 CFR 1910.157 gives no height, only that extinguishers be readily accessible without risk of injury. OSHA's eTool gives 5-foot and 3.5-foot guidance measured to the carrying handle, while NFPA 10 measures to the top of the unit; the 4-inch figure is bottom clearance.
What is the ADA height for a fire extinguisher cabinet?
For an unobstructed forward or side reach, cabinet hardware must be 15 to 48 inches above the floor. Check section 308 for obstructed reaches. Under 307.2, leading edges above 27 inches and at or below 80 inches may project no more than 4 inches into a circulation path.
How far apart do fire extinguishers need to be?
There is no universal spacing. For Class A hazards nobody walks more than 75 feet to an extinguisher, and one unit protects no more than 11,250 square feet. Check the actual walking path from each protected location and the allowable floor area for each extinguisher.
Does a fire extinguisher need a sign?
Where an unavoidable obstruction or a cabinet hides an extinguisher, use signs or other means to identify its location from the normal path of travel. The installation sections cited here set no sign height or size, so check local requirements.
Code references
- NFPA 10, Standard for Portable Fire Extinguishers, 2022 edition: 1.1 (scope); Chapter 3 (definitions); 5.4 and 5.5 (hazard classes and selection); 6.1 (general installation rules); 6.2 through 6.6 (Class A, B, C, D, and K); 7.2.2 (inspection items). Annexes A and E are explanatory.
- OSHA 29 CFR 1910.157: (a) scope; (b) exemptions; (c)(1) mounting and location; (d) distribution by class.
- 2010 ADA Standards for Accessible Design: 204.1 and 307 (protruding objects); 205.1 (operable parts); 308 (reach ranges); 309 (clear floor space, height, operation).
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