Wherever there is voltage, there is also the potential for an electrical incident, whether it is shock or arc flash.
How can workers be protected? What is the best way to protect them?
National Institute for Occupational Safety and Health uses a chart to show the five levels of safety measures needed to protect workers on the job, known as the hierarchy of controls for risk management. (This is a good plan to follow for work done at home, too!) The chart, from top to bottom, shows the most effective level to the least effective level. For instance, wearing PPE is a last resort, not the “first line of defense.” Levels 4 and 5, administrative controls and PPE, are considered less optimal safety measures because the focus is on the worker instead of on the hazard.
Eliminate the hazard
Substitute the hazard with a safer alternative
Physically change the work process (engineering controls)
Require training or set time limits on time of exposure to hazard (administrative controls)
Use personal protective equipment (PPE)
The following descriptions are taken from the CDC website and NIOSH’s “Hierarchy of Controls” article:
- Elimination and substitution, while most effective at reducing hazards, also tend to be the most difficult to implement in an existing process. If the process is still at the design or development stage, elimination and substitution of hazards may be inexpensive and simple to implement. For an existing process, major changes in equipment and procedures may be required to eliminate or substitute for a hazard.¹
- Engineering controls are favored over administrative and personal protective equipment (PPE) for controlling existing worker exposures in the workplace because they are designed to remove the hazard at the source, before it comes in contact with the worker. Well-designed engineering controls can be highly effective in protecting workers and will typically be independent of worker interactions to provide this high level of protection. The initial cost of engineering controls can be higher than the cost of administrative controls or PPE, but over the longer term, operating costs are frequently lower, and in some instances, can provide a cost savings in other areas of the process.¹
- An example of this is a new product being developed by GE, the GuardEon MCCB. This breaker would be especially useful on marine vessels where, if an arc flash occurs and a fire ensues while the ship is out at sea, more damage can be done because help is further away. Simply put, this breaker can perform calculations to determine how much contact wear the breaker has sustained; additionally, it has an “on-board timing functionality”, measuring the breaker’s fault reaction time, which allows testing to be done on the unit without having to remove it.
- Administrative controls and PPE are frequently used with existing processes where hazards are not particularly well controlled. Administrative controls and PPE programs may be relatively inexpensive to establish but can be very costly to sustain over the long term. These methods for protecting workers have also proven to be less effective than other measures, requiring significant effort by the affected workers.¹ In other words, electrical safety training and PPE can be made available and required by an employer, but it is up to the worker him/herself to utilize those resources while working around electricity.
According to OSHA, PPE is acceptable as a control method in the following situations:
- When engineering controls are not feasible or do not completely eliminate the hazard
- While engineering controls are being developed
- When administrative controls and safe work practices do not provide sufficient protection, and
- During emergencies when engineering controls may not be available or feasible for use.
¹ CDC (Center for Disease Control & Prevention). “Hierarchy of Controls”, Workplace Safety & Health Topics. Accessed July 13, 2015. http://www.cdc.gov/niosh/topics/hierarchy/
See e-Hazard’s electrical safety training schedule.