Name two common hazards to watch for on the roof after the opening is made?

• A. Roof decking failure or collapse risk and the presence of electrical lines or gas lines near the opening.
• B. Birds nesting and dust
• C. Sun exposure and heat
• D. Wall cracks and missing shingles

Answer: (A)

When you cut an opening for vertical ventilation, two hazards stand out right away. The first is the potential failure or collapse of the roof decking or surrounding structural members. Fire damage or weakened framing can make the area around the opening unstable, so you must watch for signs of compromised decking and avoid putting weight on suspect sections. Move carefully to solid, supported areas and use proper footing and stay-rope techniques as needed.

The second major hazard is the presence of electrical or gas lines near the opening. Hitting or disturbing a live line can cause shocks, electrocution, or gas leaks and ignition, so identify any utilities in the vicinity, keep clear of them, and coordinate with the fire department or utility companies to de-energize or cap lines before continuing work.

Other options describe issues that are less immediate risks in the opening area, such as nuisance factors (birds nesting, dust) or general heat and sun exposure, or pre-existing roof conditions (wall cracks, missing shingles) that don’t pose the same urgent, dynamic danger once the opening is made.