The transferring of hazardous materials by pumps shall be in accordance with the following:
1. The transfer of flammable or combustible liquids shall be through piping by means of approved pumps, inert gas, or water displacement. Except as required in process equipment, gravity flow shall not be used. The use of compressed air as a transferring medium shall be prohibited.
2. Pumps shall be of a type approved for pressure, temperature, and compatibility of materials transferred.
3. Positive displacement pumps shall be provided with pressure relief discharging back to the tank or to pump suction.
4. Equipment shall be designed and arranged to prevent the unintentional escape of liquids and vapors and to minimize the quantity escaping in the event of an accidental release.
5. Pumps shall be safely located and housed in the open or in fire-resistive or noncombustible structures. Motors used to pump contents from tanks shall not be located beneath such tanks.