WAC 212-17-317
Public display -- Electrical firing unit. (1) At no point shall electrical contact be allowed to occur
between any wiring associated with the electrical firing unit
and any metal object in contact with the ground.
(2) If the electrical firing unit is powered from AC
power lines, some form of line isolation shall be employed
(e.g., a line isolation transformer).
(3) The electrical firing unit shall include a key
operated switch or other similar device that greatly reduces
the possibility that unauthorized or unintentional firings can
occur.
Exception:
When the electrical firing unit is very small in size, and is only in the immediate area and attached to the wire running
to electric matches for the brief duration of the actual firing, there is no requirement for a key operated switch.
(4) Manually activated electrical firing units shall be
designed such that at least two positive actions must be taken
to apply electric current to an electric match. For example,
this might be accomplished with two switches in series, both
of which must be operated in order to pass current.
(5) Computer activated electrical firing units shall have
some form of "dead-man-switch," such that all firings will
cease the moment the switch is released.
(6) If the electrical firing unit has a built-in test
circuit, the unit shall be designed to limit the test current
(into a short circuit) to 0.05 ampere or to twenty percent of
the no-fire current of the electric match, whichever is less. Multitesters such as Volt-Ohm Meters shall not be used for
testing unless their maximum current delivering potential has
been measured and found to meet these requirements.
(7) When any testing of firing circuits is performed, no
person shall be allowed to be present in the immediate area of
fireworks that have been attached to the electrical firing
unit.