National Safety Month (Posted June 27, 2017) Hit Next to start a quick roof safety quiz! 1. Recent OSHA studies show that __% of fatal falls happen when no fall protection is in place. 25% 50% 75% 90%1 out of 52. OSHA defines a low-slope roof as a roof having a slope of less than __ inches of vertical rise for every 12 inches of horizontal length. 2 4 6 82 out of 53. According to OSHA construction rules, fall protection is required at heights of __ feet or greater. 4 6 7 ½ 103 out of 54. According to OSHA rules, an unprotected side or edge means a side or edge without a wall or guardrail system at least __ inches in height. 36 39 42 454 out of 55. Covers for holes in a roof’s surface must be able to support: 300 pounds 500 pounds Twice the body weight of workers, equipment and material imposed on them 10 times the body weight of workers, equipment and material imposed on them5 out of 5