Question

Methanol is pumped from a 55 gal drum into a pail by means of a hand operated crank pump. Describe an appropriate grounding and bonding procedure for this scenario.

Answer 1

• Step #1 - Ground the 55-gallon drum. - Grounding means you attach a conductive copper wire from the ground to the 55-gallon metal drum. You must make a good contact to the ground, which can be a metal “grounding rod” driven several feet into the earth or, if available, connect the ground wire to the cold water pipe running through the room. It is important to be sure the copper wire connects cleanly and firmly with both the metal rod in the ground and to the metal surface of the 55-gallon drum. You must make a metal to metal connection. The metal drum must not be painted at the point where the ground wire is connected.

• Step #2 - Bond a conductive wire from the metal 55-gallon drum to the metal 5-gallon container. - Again, be sure the two contact surfaces are not painted. It's always a good idea to have a safety professional, electrical engineer and your plant maintenance person test the bonding and grounding to make sure it is correctly bonded and grounded, especially when you initially implement a bonding and grounding program for flammable liquid dispensing areas. When properly grounded, the electrons to flow harmlessly from the liquid, through the wire, to ground. The drum and smaller container have the same electrical potential (voltage) and a spark will not jump from the dispensing nozzle to the can. [See diagram on the proper layout.]