If there is reason to believe that a charge has not exploded, what is the minimum wait time when a fuse and cap are used?

• A. 30 minutes in snow blasting, 60 minutes otherwise
• B. 30 minutes
• C. 60 minutes in snow, 120 minutes otherwise
• D. 45 minutes in snow, 90 minutes otherwise

Answer: (A)

When a charge may not have exploded, treat it as a misfire and wait before approaching or re-igniting. The minimum wait depends on conditions: 30 minutes if you’re blasting in snow, and 60 minutes in other conditions. The idea is to give any residual energy and gases time to dissipate safely. Snowy, damp conditions tend to cool and dampen potential latent energy, allowing a shorter waiting period, while dry conditions can allow heat and pressure to persist longer, requiring a longer wait. After this waiting period, proceed with safety checks and the appropriate misfire procedures.