WAC 296-52-807
Avalanche control blasting. (1) The
employer shall ensure that all members of avalanche control
blasting crews are competent ski mountaineers in good physical
and mental condition.
(2) Each avalanche control blasting crew or team shall
consist of a qualified and licensed blaster and at least one
trained assistant.
(3) Untrained personnel may accompany blasting crews for
training purposes but shall not participate in actual firing
of charges until trained and authorized.
(4) The blaster in charge of each crew or team shall be
responsible for all phases of preparation and placement of
charges.
(5) Avalanche control blasting should be conducted during
daylight hours whenever possible.
(6) Escape route.
(a) The avalanche control crew or team shall preplan the
escape route before igniting any charge.
(b) The escape route shall be as safe and foolproof as
possible and shall culminate behind a terrain barrier or at
least one hundred feet from the blast site by the time of
detonation.
(7) Hand-thrown charges.
(a) A blaster shall only work with one charge at a time.
(b) Before attaching the igniter, the blaster must:
(i) Be at the start of the escape route;
(ii) Check the runout zone for personnel;
(iii) Check the blast area for personnel.
(c) After the blaster attaches and activates the igniter:
(i) The blaster shall check to see that the fuse is
ignited;
(ii) If the fuse did not ignite, no attempt shall be made
to relight it. The blaster shall immediately remove the fuse
cap from the charge to sidearm it. The fuse cap shall be
treated as a misfire and be put in an appropriately safe place
separate from all other explosive components. It shall not be
approached for at least thirty minutes, after which time it
shall be properly disposed of;
(iii) The practice of double fusing hand charges shall be
allowed. An attempt shall be made to light both fuses. If
only one of the two fuses lights, the charge shall be deployed
as normal;
(iv) As soon as the fuse is ignited, the blaster shall
promptly throw the charge into the target area;
(v) All personnel shall be in a safe place when the
charge detonates.
(d) Where hand-thrown charges will slide down the hill on
hard frozen snow or ice surface, charges shall be belayed with
light cord.
(8) Hand charges thrown from ski lifts or trams.
(a) The number of charges thrown from ski lifts or trams
shall be kept to a minimum.
(b) The lift operating crew shall be informed of the
blasting plans.
(c) The lift crew shall stand by for emergency procedures
such as transfer of lift onto auxiliary power, evacuation,
etc.
(d) The lift crew and the blaster in charge shall be in
direct radio contact at all times during the blasting
operations.
(e) Only the avalanche control blasting crew and the
essential lift operating personnel shall be on a lift or tram
during blasting operations.
(f) The avalanche control blasting crew shall be
traveling up slope when a charge is thrown.
(g) A charge shall always be thrown down slope and to the
side, away from towers, haulropes and other equipment or
facilities.
(h) The minimum distance from the blast target to the
closest point of the lift shall be sixty feet.
(i) Hand charges shall not exceed 4.5 pounds of TNT
equivalent.
(j) Fuses shall be timed and cut to such length that all
personnel on the lift will have moved a minimum of three
hundred feet from the blast target by the time of detonation.
(k) Precautions shall be taken to avoid tossing charges
into any of the lift equipment, moving chairs, cables, towers,
etc.
(9) Aerial avalanche control blasting.
(a) Blasting from aircraft shall require a written
program approved by the Federal Aviation Administration and
the director, or designee of the department of labor and
industries.
(b) A written program shall include the following:
(i) Written procedures to be followed including
provisions for safety in the avalanche runout zone and
emergency rescue plans.
(ii) Hand charge makeup and handling procedures.
(iii) The type of explosives to be used.
(iv) The qualifications of all avalanche control
personnel involved in aerial blasting must meet the
requirements of WAC 296-52-64030.
(v) The specific locations where aircraft blasting is to
take place.
(c) An aerial avalanche control team shall be established
consisting of (at minimum) a pilot, a blaster in charge and an
observer/controller.
(d) Blasting from an aircraft shall require the blaster
in charge to be a licensed avalanche blaster with an
endorsement for aerial blasting. The blaster in charge will
be on board during each aerial blasting mission.
Note:
Blasting from aircraft should only be used when it is determined that conventional methods are not the safest means to
mitigate the existing avalanche hazard.
(10) Avalauncher requirements.
(a) Management shall develop a written training program
and ensure that every person who will be authorized to work on
an avalauncher firing team is thoroughly trained. Training
shall include:
(i) All operating instructions;
(ii) Safety precautions;
(iii) Emergency procedures;
(iv) Securing requirements for the equipment.
(b) Each employer shall have a list of authorized
operators listed on a posted operator's list.
(c) Only trained and authorized personnel shall be
permitted to point and fire an avalauncher with explosive
rounds.
(d) During firing of explosive loaded rounds, the firing
team shall consist of two qualified operators and not more
than one adequately trained helper.
(e) Operators must have a current state blasting license.
(f) Each operator shall individually check the elevation,
pointing and pressure settings of the gun before each shot is
fired.
(g) Operators shall attempt to determine and record
whether or not each round which is fired actually explodes on
contact.
(h) The approximate location of all known misfired
explosives (or duds) shall be recorded.
(i) Initial shooting coordinates for each avalauncher
mount shall be made during periods of good visibility.
(j) Testing shall include test firing in various wind
conditions.
(k) The correct coordinates for the various conditions
encountered shall be carefully recorded.
(l) When spotter personnel are used in the target area,
shooting shall be conducted with nonexplosive projectiles.
(m) Firing of explosive avalauncher rounds shall only be
conducted when personnel are not in the target area.
(n) The avalauncher apparatus shall be stored in a
nonfunctional condition when not in use. This shall be
accomplished by:
(i) Locking out the firing mechanism or gas source in
accordance with the lockout requirements of this chapter; or
(ii) Disassembly of functional components rendering the
gun inoperable and separate storage of components removed; or
(iii) Removal of the entire gun to secure storage.
(o) With established avalauncher mounts, each autumn when
reinstalling guns, the following procedures shall be
accomplished before the gun is considered operable:
(i) All components shall be carefully inspected by
qualified personnel;
(ii) After assembly and installation, the gun shall first
be test fired using a nonexplosive projectile;
(iii) The established firing coordinates shall be checked
by test firing.
(11) Cornice control requirements.
(a) Cornice buildup hazards shall be evaluated regularly
by qualified personnel, particularly after heavy snowfall
periods which are accompanied by high wind or other snow
transport weather conditions.
(b) Cornice hazards shall be controlled whenever the
buildup appears to offer potential hazard to areas accessible
by personnel.
(c) The control team shall establish the tension
breakline of the cornice roof as accurately as conditions
permit before starting any other control work on the cornice.
(d) The tension breakline shall be marked when necessary.
(e) Small lightly packed cornices may be kicked off with
a ski, ski pole, or shovel by an unbelayed control team member
if the ridgeline can be clearly established and all work can
be done from the safe side of the ridgeline.
(f) When working along an anticipated cornice breakline,
control team members shall retreat back from the breakline to
change work positions rather than traverse along the
breakline.
(g) The following factors shall be given careful
consideration before commencing control activities on any
relatively larger cornice:
(i) The older and larger a cornice becomes, the more
densely it compacts. Densely packed cornices release into
larger blocks offering a higher level of danger to an extended
runout zone. The control team leader shall therefore take
highest level of precautions to assure that the runout zone is
clear of personnel;
(ii) Larger size cornices result in increased suspended
weight and leverage which may cause the breakline release
fracture to occur behind the actual ridgeline. The actual
ridgeline may also be obscured by the simple mass of larger
cornices. Control team members shall stay off the cornice
roof and must be protected by a secure belay when working near
the suspected breakline;
(iii) All large cornices shall be released by explosives.
Explosives shall be transported, made up and fired in
accordance with the following requirements:
(A) The ignition system for single hand charge blasts
shall be safety fuse and cap or a system approved by the
department.
(B) Detonating cord or shock tube shall be used to
connect multiple charge blasts.
(C) When detonating cord is used, one end shall be
securely anchored where premature cornice collapse will not
disturb the anchor. The fuse and cap shall be attached to the
free end of the detonating cord after all charges are
connected to the detonating cord.
(D) Safety fuse length shall be sufficient to permit
adequate escapement time for all personnel from the area
influenced by the blast. Safety fuse shall be not less than
three feet long, approximately two minutes and twenty seconds,
in all instances.
(h) Cornice control work on large cornices shall be
conducted during daylight hours and preferably during
favorable weather conditions. As a minimum, clear visibility
shall exist across the full length of any cornice which the
control team is attempting to release.
(12) Belaying practices.
(a) Belay rope shall be standard 11 mm mountaineering
rope or the equivalent.
(i) Belay rope shall be inspected at not less than
thirty-day intervals and maintained in excellent condition.
(ii) Defective belay rope shall not be used for belaying
purposes.
(b) Adequate trees or other suitable natural belay
anchors shall be used in preference to a human belay anchor
when such natural anchors are available.
(c) The belay anchor position shall be as near to ninety
degrees from the tension breakline as the terrain conditions
will permit.
(d) With either a natural belay anchor or human belay
anchor, the belay line shall be tended to keep slack out of
the line.
(e) When either the belayed person or belay anchor needs
to change position, the belayed person shall retreat back from
the cornice to a safe position until the belay anchor is
reestablished.
(f) When a human belay anchor is used:
(i) The belay anchor person shall establish the anchor
position as far back away from the cornice as conditions
permit;
(ii) The anchor person shall remain in a seated position
with their legs pointed toward the belayed person until such
time as the belayed person has retreated back from the cornice
to a position considered to be safe.