Section 77.208 - Storage of materials(a) Materials shall be stored and stacked in a manner which minimizes stumbling or fall-of-material hazards.(b) Materials that can create hazards if accidentally liberated from their containers shall be stored in a manner that minimizes the dangers.(c) Containers holding hazardous materials must be of a type approved for such use by recognized agencies.(d) Compressed and liquid gas cylinders shall be secured in a safe manner.(e) Valves on compressed gas cylinders shall be protected by covers when being transported or stored, and by a safe location when the cylinders are in use.36 FR 9364, May 22, 1971, as amended at 67 FR 42389 , June 21, 2002