FLAMMABLE COMPRESSED GASES questions and
answers with solutions 2025
Combustible Waste - ANSWER Any substance, item or other organic or inorganic matter that presents a
fire hazard and is a byproduct or residue of the construction, use or occupancy of any premises, or any
activity conducted thereon, that has no economic value in connection with such use or occupancy.
Compressed Gas - ANSWER A material, or mixture of materials that is a gas at 68F or less at 14.7 psia of
pressure; and has a boiling point of 68F or less at 14.7 psia that is either liquefied, non-liquefied or in
solution at that temperature and pressure, except gases which have no other health-or physical-hazard
properties that are not considered to be compressed until the pressure in the packaging exceeds 41 psia
at 68F
Compressed Gas Container - ANSWER A pressure container designed to hold compressed gases at
pressures greater than 1 atmosphere at 68F. A compressed gas container is a container that stores highly
pressurized gas.
Compressed Gas System - ANSWER An assembly of components, such as containers, reactors, pumps,
compressors and connecting piping and tubing, designed to contain, distribute or transport compressed
gases.
Containment system - ANSWER A gas-tight recovery system comprised of devices or equipment which,
when placed over or around the portion of the compressed gas container that is leaking, stops or
controls the escape of gas from the container
Containment vessel - ANSWER A gas-tight vessel which, when installed or placed over or around a
leaking compressed gas container, confines the container and the gas leaking there from.
DOTn - ANSWER United States Department of Transportation, n=US regulations, not Canadian
Explosion - ANSWER An effect produced by the sudden violent expansion of gases, whether or not
accompanied by a shock wave or disruption, of enclosing materials
, Excess Flow Valve - ANSWER A valve inserted into a compressed gas container that is designed to shut off
the flow of gas in the event that its predetermined flow is exceeded
Excess Flow Control - ANSWER A fail-safe system or other approved device, equipment or system
designed to shut off flow caused by a rupture in a pressurized piping system.
Exhausted Enclosure - ANSWER A device, typically consisting of a hood equipped with a fan that serves
to capture and exhaust fumes, mist, vapors and gases generated at a workstation or other local
environment. An exhausted enclosure does not include a room provided with general ventilation
Gas Room - ANSWER A separately ventilated, fully enclosed room in which only compressed gases and
associated equipment and supplies are stored or used.
Manifold - ANSWER Multiple tanks that are connected together to operate as one system
Nesting - ANSWER A method of securing flat-bottomed compressed gas containers upright in a tight
mass using a contiguous three-point contact system whereby all containers within a group have a
minimum of three points of contact with other containers, walls or bracing.
Oxidizing Gas - ANSWER A gas that car support and accelerate combustion of other materials.
What is compressed flammable gas? - ANSWER It is any gas that is ignitable in a mixture of 13% or less
(by volume) with air, or the flammable range with air is at least 12%, regardless of the lower limit, at
atmospheric temperature and pressure.
Examples of FLAMMABLE GASES include: - ANSWER Acetylene
Hydrogen
Methane
Methylamine
Carbon Monoxide
Hydrogen-Sulfide
Vinyl chloride