29 C.F.R. § 1926.106 : Labor — REGULATIONS RELATING TO LABOR — OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR — SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION — PERSONAL PROTECTIVE AND LIFE SAVING EQUIPMENT — Working over or near water

(a) Employees working over or near water, where the danger of drowning exists, shall be provided with U.S. Coast Guard-approved life jacket or buoyant work vests.
(b) Prior to and after each use, the buoyant work vests or life preservers shall be inspected for defects which would alter their strength or buoyancy. Defective units shall not be used.
(c) Ring buoys with at least 90 feet of line shall be provided and readily available for emergency rescue operations. Distance between ring buoys shall not exceed 200 feet.
(d) At least one lifesaving skiff shall be immediately available at locations where employees are working over or adjacent to water.

29 C.F.R. §1926.106