3.5 Fire Protection (Subpart L): Extinguishers, Fixed Systems, Detection & Employee Alarms (1910.155-1910.165)

3.5 Fire Protection (Subpart L): Extinguishers, Fixed Systems, Detection & Employee Alarms

Where Subpart L Sits Relative to Subpart E

Subpart E, covered in the previous section, is about getting people out: exit routes, Emergency Action Plans, and Fire Prevention Plans. Subpart L (1910.155 through 1910.165) is about the equipment that fights the fire and the systems that tell people to leave. OSHA 511 treats emergency and fire protection as a single module, and exam questions routinely pair a 1910.38 EAP requirement with a 1910.157 extinguisher requirement in the same stem. Keep the two subparts separate in your book and in your head.

Subpart L contains:

Portable Fire Extinguishers (1910.157)

The Threshold Question: Are You Required to Have Them At All?

1910.157(b)(1) contains the exemption most candidates miss. Where the employer has established and implemented a written fire safety policy requiring the immediate and total evacuation of employees upon the alarm, and has an emergency action plan and fire prevention plan meeting 1910.38 and 1910.39, the employer does not have to comply with the distribution, inspection, maintenance, testing, and training requirements of 1910.157 - because no employee is expected to use an extinguisher. Removing extinguishers from the building is not required; committing in writing to total evacuation is what triggers the relief.

Mounting, Location, and Travel Distance (1910.157(c) and (d))

Extinguishers must be mounted, located, and identified so that they are readily accessible to employees without subjecting the employees to possible injury (1910.157(c)(1)). Only approved extinguishers may be used, and carbon tetrachloride and other toxic vaporizing-liquid extinguishers are prohibited (1910.157(c)(3)).

Distribution is by fire class, and the numbers are the ones the exam asks for:

Note the logic: Class C is not a distance rule at all, because an energized electrical fire is still fundamentally an A or B fire with an ignition source attached. Class D extinguishing agents must also be located in the immediate vicinity of the combustible metal operation.

Inspection, Maintenance, and Testing (1910.157(e) and (f))

Three intervals, three different activities - candidates mix these up constantly:

1. Monthly visual inspection - 1910.157(e)(2). A quick check that the extinguisher is in its designated place, unobstructed, has a full charge indication, and shows no obvious damage. The employer records the check.
2. Annual maintenance check - 1910.157(e)(3). A thorough examination of the mechanical parts, extinguishing agent, and expelling means. The employer must record the annual maintenance date and retain that record for one year after the last entry or the life of the shell, whichever is less.
3. Hydrostatic testing - 1910.157(f) and Table L-1. Pressure testing of the cylinder itself, at intervals ranging from 5 years (soda acid, cartridge-operated water and foam, wetting agent, water, loaded stream) to 12 years (dry chemical with mild steel, brazed brass, or aluminum shells; stored-pressure and cartridge-operated dry chemical; halogenated agents; carbon dioxide). Testing must be performed by trained persons with suitable equipment and facilities.

Stored-pressure extinguishers requiring a 12-year hydrostatic test must be emptied and subjected to maintenance procedures every 6 years (1910.157(e)(3)). Extinguishers removed from service for maintenance or recharge must be replaced with an alternate providing equivalent protection.

Training (1910.157(g))

Where the employer has provided extinguishers for employee use, employees must be trained on the general principles of extinguisher use and the hazards involved with incipient stage firefighting upon initial assignment and at least annually thereafter (1910.157(g)(1)-(2)). Employees designated to use firefighting equipment as part of an emergency action plan get additional training in the use of that equipment on assignment and at least annually.

Fire Brigades (1910.156)

If an employer chooses to organize employees into a fire brigade, 1910.156 attaches. The employer must prepare a written organizational statement describing the brigade's basic structure, training, expected number of members, and the functions the brigade will perform. Employees expected to do interior structural firefighting must be physically capable of performing the duties, and the employer must not permit employees with known heart disease, epilepsy, or emphysema to participate unless a physician certifies fitness. Training and education must be provided before performing brigade duties and at least annually; members expected to perform interior structural firefighting are trained or educated at least quarterly. Protective clothing and SCBA must be provided at no cost, and interior structural firefighters must use positive-pressure SCBA in accordance with 1910.134.

Fixed Systems, Standpipes, and Sprinklers (1910.158 - 1910.163)

• 1910.158 - Standpipe and hose systems. Hose stations must be conspicuously located and unobstructed, with hose designed for the pressure, water supply, and flow demanded.
• 1910.159 - Automatic sprinkler systems. The employer must maintain a minimum vertical clearance of 18 inches (45.7 cm) between the top of storage and sprinkler deflectors, so that stacking does not block spray patterns. Sprinkler systems must be protected against mechanical damage, have proper water supply, and receive a main drain flow test annually, with inspector's test valve operation and hydraulic design information maintained.
• 1910.160 - 1910.163 - Fixed extinguishing systems. These cover general requirements plus dry chemical, gaseous agent, and water spray and foam systems. The key general-industry point is that where a fixed system discharges an agent that could expose employees to a hazardous atmosphere (notably total-flooding gaseous agents), the employer must provide pre-discharge alarms and a time delay sufficient for evacuation, plus training and signs.

Fire Detection and Employee Alarm Systems (1910.164 and 1910.165)

1910.164 requires fire detection systems and their components to be approved, protected from corrosion, restored to normal operating condition promptly after each test or alarm, and serviced and maintained by trained personnel. Detectors must be tested and adjusted as often as needed to maintain reliability.

1910.165 governs the employee alarm system that ties the whole emergency program together:

• The alarm must provide warning for necessary emergency action as called for in the emergency action plan (1910.165(b)(1)).
• It must be capable of being perceived above ambient noise or light levels by all employees in the affected portions of the workplace, with tactile devices for employees who could not otherwise recognize the audible or visual alarm (1910.165(b)(2)).
• The alarm must be distinctive and recognizable as a signal to evacuate the work area or to perform actions designated under the EAP (1910.165(b)(3)).
• Workplaces with 10 or fewer employees may use direct voice communication if all employees can hear the alarm, and no backup system is required (1910.165(b)(5)).
• Testing: non-supervised employee alarm systems must be tested every two months, using a different actuation device in each consecutive test (1910.165(d)(2)); supervised employee alarm systems must be tested at least annually (1910.165(d)(4)).
• Manual actuation devices must be unobstructed, conspicuous, and readily accessible (1910.165(e)).