Across our industry, I have found all kinds of policies for grounding trucks. I also have found that in many cases, employers’ rules for grounding trucks are not based on OSHA requirements and – even more concerning – are not based on sound principles of protection. I believe the grounding policies are well intentioned, but they fail to achieve two important goals: (1) meeting the OSHA standard and (2) protecting workers where electrical contact hazards exist. So, let’s take an ABCs approach to the issue because even though some detailed explanation is required, it really is that simple.
A Defensible Plan
You must be able to defend your plan or policy. This is the case for every plan or policy. Defense is built around establishing and accomplishing a goal, understanding the hazard, understanding the mitigation of the hazard, training at-risk employees, and conducting periodic audits to ensure the plan or policy is properly employed.
In our case, the goal is protecting workers from electrical hazards created by contact with mobile equipment. Let’s agree here that mobile equipment is anything that is moved into a work site. In addition, it is mobile equipment that can become energized. If it can’t become energized, it is not a hazard.
Understanding the Hazard
The hazard is energizing mobile equipment and the transfer of hazardous energy to an employee who is on, in contact with or near the equipment that has become energized. The hazard involves unintended or inadvertent energizing. There can be several energizing sources, but we can classify them as follows: direct contact with an energized source, capacitive coupled voltage or inductive coupled current (I’ll explain this a little later), and inadvertent energizing by grounding to a current-carrying source. Let’s start with this one first.