(a) The burning
rate of each spool of safety fuse to be used shall be measured, posted in
locations which will be conspicuous to safety fuse users, and brought to the
attention of all persons involved with the blasting operation.
(b) When firing with safety fuse ignited
individually using handheld lighters, the safety fuse shall be of lengths which
provide at least the minimum burning time for a particular size round, as
specified in the following table.
TABLE E-1-SAFETY FUSE-MINIMUM BURNING TIME
|
Number of holes in a round
|
Minimum burning time
|
|
1 ...............................
|
....... 2 minutes/1
|
|
2-5 ............................
|
........ 2 minutes 40 seconds
|
|
6-10 ..........................
|
......... 3 minutes 20 seconds
|
|
11 to 15 ...................
|
........... 5 minutes.
|
1/For example, at least a 36-inch length of
40-second-per-foot safety fuse or at least a 48-inch length of
30-second-per-foot safety fuse would have to be used to allow sufficient time
to evacuate the area.
(c)Where flyrock might damage exposed safety
fuse, the blast shall be timed so that all safety fuses are burning within the
blastholes before any blasthole detonates.
(d) Fuse shall be cut and capped in dry
locations.
(e) Blasting caps shall
be crimped to fuse only with implements designed for that purpose.
(f) Safety fuse shall be ignited only after
the primer and the explosive material are securely in place.
(g) Safety fuse shall be ignited only with
devices designed for that purpose. Carbide lights, liquefied petroleum gas
torches, and cigarette lighters shall not be used to light safety
fuse.
(h) At least two persons
shall be present when lighting safety fuse, and no one shall light more than 15
individual fuses. If more than 15 holes per person are to be fired, electric
initiation systems, igniter cord and connectors, or other nonelectric
initiation systems shall be used.
EXTRANEOUS ELECTRICITY
