Roof Sailing Wind and Weather Assessment

Question 1

Which Beaufort wind scale number corresponds to a sustained wind speed of approximately 25–31 mph (fresh breeze)?

Accepted Answer

Force 5

Answer

Beaufort Force 5 (fresh breeze) corresponds to sustained winds of approximately 19–24 knots (25–31 mph), causing small trees to sway.

Question 2

What weather condition creates the most significant ice hazard on roofing surfaces in the US?

Accepted Answer

Freezing rain (glaze ice)

Answer

Freezing rain creates a thin, nearly invisible glaze ice layer that is far more slippery than packed snow or frost.

Question 3

What is the primary danger of working on a roof during thunderstorm conditions?

Accepted Answer

Lightning strike risk — workers are the highest point

Answer

Workers on rooftops are elevated and exposed, making them prime lightning strike targets during thunderstorms.

Question 4

Which type of cloud formation is the most reliable indicator of imminent severe weather requiring work stoppage?

Accepted Answer

Cumulonimbus

Answer

Cumulonimbus clouds are towering storm clouds that produce lightning, heavy rain, hail, and tornadoes — all requiring immediate work stoppage.

Question 5

What relative humidity level begins to significantly increase the risk of heat stroke for workers performing heavy physical labor on rooftops?

Accepted Answer

Above 60%

Answer

Relative humidity above 60% significantly reduces the body's ability to cool itself through sweat evaporation, increasing heat stroke risk.

Roof Sailing Practice Test