Subpart P
An "alarm" is a signal or message that tells people there is a fire, medical emergency, or other situation needing emergency response or evacuation. See the definition in 1915.509.
A Class II standpipe system is a 1½ inch (3.8 cm) hose system intended to control or extinguish incipient stage fires. See the definition in 1915.509.
A "contract employer" is an employer (for example, a painter, joiner, carpenter, or scaffolding subcontractor) who performs work under contract to the host employer or another contractor at the host’s worksite, excluding employers who provide only incidental services like mail delivery or office supplies. See 1915.509 for the definition and review OSHA guidance on multi-employer workplaces in related sections of 1915.
A "dangerous atmosphere" is any atmosphere that could expose employees to death, incapacitation, injury, acute illness, or loss of self-rescue ability (unable to escape unaided), and recognizing it is critical because it triggers safe-entry, monitoring, and rescue procedures. See the definition in 1915.509 and consider the competent person guidance in OSHA's interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2016-04-18.
A "drop test" is a leak-test method using gauges to confirm the integrity of an oxygen-fuel gas burning system, and any drop in pressure during the test indicates a leak. See 1915.509 for the definition.
"Emergency operations" are activities by fire response organizations related to rescue, fire suppression, emergency medical care, and special operations at the scene of an incident, including all activities performed there. See the definition in 1915.509.
"Fire response" is the employer's action during a fire emergency (including suppression or evacuation), while a "fire watch" is the activity of observing and responding to fire hazards specifically associated with hot work and the employees assigned to that task. See both definitions in 1915.509 and consult hot work and fire watch training sections in 1915.508(b).
A "fire response employee" is a shipyard worker who performs shipyard firefighting duties as set out in the fire safety plan. Their responsibilities include carrying out assigned firefighting and rescue tasks according to that plan. See the definition in 1915.509 and review fire safety program details in 1915.508.
A "fire response organization" is an organized, trained group that responds to shipyard fire emergencies—examples include fire brigades, shipyard fire departments, private contractual departments, and municipal fire departments. See 1915.509 for the definition.
"Fire suppression" means activities to control and put out fires; portable extinguishers and small hose systems are appropriate for incipient stage fires that can be controlled without protective clothing or breathing apparatus. See the definitions of "fire suppression" and "incipient stage fire" in 1915.509.
A "fixed extinguishing system" is a permanently installed system that extinguishes or controls fires in the space it protects; a "protected space" is any space into which that fixed system can discharge. Both definitions are in 1915.509.
A "flammable liquid" is any liquid with a flashpoint below 100 ºF (37.8 ºC), except mixtures where components with flashpoints of 100 ºF or higher make up 99 percent or more of the mixture. See the definition in 1915.509.
A "hazardous substance" is any substance likely to cause injury because it is explosive, flammable, poisonous, corrosive, oxidizing, an irritant, or otherwise harmful; recognizing these substances helps determine needed controls and PPE. See 1915.509.
"Hose systems" are fire protection systems composed of a water supply, approved fire hose, and a means to control water at the hose output; "small hose systems" are hoses from 5/8" up to 1½" diameter intended for employee use to control incipient stage fires. See both definitions in 1915.509.
A "host employer" is the employer in charge of coordinating work or who hires other employers at a multi-employer workplace; they have responsibility for coordinating safety among contractors and ensuring workplace controls are in place. See the definition in 1915.509 and the OSHA interpretation about competent persons and employer responsibilities at https://www.osha.gov/laws-regs/standardinterpretations/2016-04-18.
An "incident management system" is a system that defines roles, responsibilities, and procedures used to manage and direct emergency operations; it provides organized command and control during incidents. See the definition in 1915.509.
An "incipient stage fire" is a beginning-stage fire that can be controlled or extinguished by portable fire extinguishers, a Class II standpipe, or small hose systems without needing protective clothing or breathing apparatus. See the definition in 1915.509.
"Inerting" is displacing the atmosphere in a permit space with a noncombustible gas (like nitrogen) to make it noncombustible, but this procedure produces an IDLH oxygen-deficient atmosphere and creates serious hazards for entrants. See the definition in 1915.509.
"Interior structural firefighting operations" are firefighting or rescue activities inside buildings, enclosed structures, vessels, or vessel sections where the fire is beyond the incipient stage; these are higher‑risk operations requiring specialized training and equipment. See the definition in 1915.509.
A "multi-employer workplace" is any workplace with a host employer and at least one contract employer; fire protection planning must address the roles and coordination among all employers on site. See the definition in 1915.509 and the competent person employer responsibilities in https://www.osha.gov/laws-regs/standardinterpretations/2016-04-18.
A PASS is a device that emits a loud signal if the wearer becomes immobilized or is motionless for 30 seconds or more; it is used to locate and rescue trapped or incapacitated firefighters. See the definition in 1915.509.
"Physical isolation" eliminates a fire hazard by removing it from the work area (at least 35 feet for combustibles), covering/shielding it with fire-resistant material, or otherwise preventing the hazard from entering the work area; "physically isolated" refers to positive isolation of a supply from the distribution piping of a fixed extinguishing system (for example, removing a spool piece and installing a blank flange or using a double block and bleed). See the definitions and examples in 1915.509.
"Proximity firefighting" is specialized firefighting for very high-heat incidents (like aircraft or bulk fuel fires) that requires specialized thermal protection and is usually exterior; it is not entry firefighting and is distinct from interior structural firefighting. See the definition in 1915.509.
A "qualified instructor" is a person with the specific knowledge, training, and experience to teach the required fire response or fire watch material found in 1915.508(b) or 1915.508(c). Employers must ensure instructors are competent to cover the required topics. See the definition in 1915.509 and the training content requirements in 1915.508.
"Rescue" means locating endangered persons at an incident, removing them from danger, treating the injured, and transporting them to an appropriate health care facility. See the definition in 1915.509.
"Shipyard firefighting" is rescue, fire suppression, and property conservation involving buildings, enclosed structures, vehicles, vessels, aircraft, or similar properties in a fire or emergency. See the definition in 1915.509.
A "small hose system" is a hose assembly from 5/8" (1.6 cm) up to 1½" (3.8 cm) diameter intended for employee use to control or extinguish incipient stage fires. Employees should use it only for fires that are at the incipient stage and can be handled without protective clothing or breathing apparatus. See 1915.509.
A "standpipe" is a fixed piping system with hose connections used to supply water to approved hose lines or sprinkler systems; the hose may or may not be connected to the system. See the definition in 1915.509.