Warning Signal Protocol

Pre-blast and all-clear signal procedures

Key Requirements

120

dB minimum

At source

30s

Minimum duration

Continuous signal

0% complete

Sound the pre-blast warning signal at minimum 120 dB at source

Critical

s.165(1)

Signal must be audible throughout the entire danger zone

Continue the warning signal for minimum 30 seconds

Critical

s.165(1)

Verify all persons have cleared the danger area (50m minimum)

Critical

s.146

Conduct visual sweep of entire blast area

Confirm all roads and approaches are guarded

Critical

s.163

Verify warning signs are posted at all access points

s.163

Confirm radio communication with all guards

Initiate blast only when all-clear is confirmed

Critical

Sound all-clear signal after blaster inspection confirms safe conditions

Critical

s.165(2)

Inspect for misfires, flyrock, and unstable ground before all-clear

PRE-BLASTLong continuous signal

30s+

ALL-CLEARSeries of short signals

3×

Reference: NB Reg 91-191, Section 165