C-4 is 1.15 times more powerful than TNT (1 pound of
Firing Device-A device that causes the initiation of
Composition C-4 is equivalent to 1.15 pounds of TNT).
demolition charges either directly or through its effect on
a blasting cap, electric squib, or detonating cord. It may
Explosives Facility-Any structure or location containing
be electrical, mechanical, or electromechanical.
ammunition and explosives.
Fixed Ammunition-Includes all but small arms and
Explosives Hazard--Any condition which may result in or
rocket ammunition. Consists of cartridge case, loaded
contribute to the severity of an explosives accident or
with propellant, firmly attached to the projectile. Such
ammunition is loaded in one operation into the weapon.
Explosives Safety Distance (Quantity Distance)-The
Flameproof-Combustible materials (e.g., clothing) so
pre-scribed minimum distance between various classes
treated or coated as to decrease their burning
and quantities (net weight) of explosives and between
such explosives and specified exposures (inhabited
buildings, public highways, public railways, petroleum,
Flammable-Combustible material easily ignited and
aircraft, etc.) affording an acceptable degree of
which burns readily.
protection and safety.
Flammable Liquid-Any liquid, the vapor of which will
Exposed Explosives-Those actually visible (unpackaged
bulk explosives, disassembled or open components,
etc.) and that also are susceptible to initiation directly by
Fragment Distance-The limiting range of a considerable
static or mechanical spark. Explosives that create,
number of fragments from the quantity and types of
accidentally or otherwise, explosives dust or give off
explosives involved in certain explosives safety-
vapors, fumes or gases in explosive concentrations.
distance (quantity-distance) tables. (Formerly referred
to as missile distance for ammunition in 1.2-1.3 based
Field Office-An office required by operational super-
on the limiting range of a considerable number of
vision (e.g., foremen and line supervisors) in direct
fragments for the type of ammunition involved. The
support of ammunition and explosives operations.
distances do not take into account occasional fragments
which may be projected farther. For class 1.1,the
inhabited-building distance is based upon blast damage
Firebrand-A projected burning or hot fragment whose
and does not represent the distance to which some
thermal energy is transferred to a receptor.
fragments can be projected.
Fire Hazard Area-A location in which the primary, but
Fragmentation-The breaking up of the confining material
not necessarily the only hazard is that of fire, including
explosions of gas or vapor and air mixtures.
of a chemical compound or mechanical mixture when
an explosion takes place. Fragments may be complete
items, subassemblies, or pieces thereof, as well as
Fire Resistive-Structures, materials, etc., designed to
pieces of equipment or buildings containing the items.
resist fire without becoming weakened to the point of
Fuse-A slow-burning powder filled cord that carries
Fire Retardant-Generally combustible structures, mater-
flame through its length at a known and uniform rate per
ials, etc., so treated or covered as to retard ignition or
unit of length. Also known as "safety fuze", "time fuze"
spread of fire.
and "time blasting fuze."
Fire Wall/Fire Division Wall -A wall of fire-resistive con-
Fuze-(Not to be confused with fuse). A mechanical
struction designed to prevent spread of fire from one
electrical, or electromechanical device used to function
side to the other.
an explosive device such as a bomb or projectile. In
demolition work, a firing device may be termed a fuze.