OSHA Finally Starts Fining Companies for Endangering the Lives of Workers
St. Louis, MO – Who’s going to catch us? The mattress-tag police? Unfortunately, this is the attitude many an electrical engineer faces when discussing electrical grounding problems with upper management. There simply seems to be no one minding the store when it comes to electrical grounding violations.
Or at least so thought the management of American Pulverizer Co., a reduction equipment manufacturing facility in St. Louis, Missouri; until they got caught by OSHA and fined $121,100.00. The company was cited this month (August 2011) for one repeat, 31 serious, and one other-than-serious safety violations (paperwork) in regards to electrical grounding. Specifically the continuity between metallic chassis’ back to the main electrical panels ground.
Starting with a single citation in October of 2006 and then additional citations in February of 2011, the American Pulverizer Co., was finally issued $121,100 in fines in August of 2011 due to repeat violations for a lack of grounding continuity in electrical equipment. These serious violations in grounding continuity address multiple hazards that could result in either death or serious physical harm, associated with cranes, lockout/tagout of energy sources, powered industrial trucks, electrical equipment, flammable liquids and gas, welding, housekeeping and machine guarding.
“There is no excuse for such lack of attention to hazards in the work environment,” said Charles Adkins, OSHA’s regional administrator in Kansas City, Mo. “It is imperative that employers take the necessary steps to provide a safe workplace for all employees in order to prevent needless injuries or worse.”
American Pulverizer Co., is not alone, OSHA has recently started a new program out of their local offices that emphasis electrical safety in general industry establishments. Under the Occupational Safety and Health Act of 1970, employers are responsible for providing safe and healthy workplaces for their employees, which includes the elimination of known electrical hazards. Un-grounded metallic chassis present a shock hazard to personnel.
In technical terms, when OSHA mentions “grounding continuity”, it is really discussing the Ground Potential Difference (GPD) between the various machine parts. A properly grounded facility will have a Ground Potential Difference of less than 0.5-ohms, often less than 0.1-ohms. This is measured from the main ground source at the electrical panel to any metallic chassis found at the facility. True Direct-Current (DC) measurement devices should be used to make these readings, as Alternating-Current (AC) systems will have additional impedance issues that could provide erroneous measurements.
The Ground Potential Difference (GPD) is not only important for personnel safety, but it is important for the proper operation of electronic equipment. In regards to personnel safety, a low GPD indicates that an effective ground path exists back to the first-service disconnect and the main Over Current Protection Device (OCPD) or circuit breaker protecting personnel from electrical shock. On a regular daily use, a low GPD means that unwanted stray electrical currents, harmonics, transients, and general electrical noise, will travel to earth on the grounding system, and not through the shield wires of sensitive data and communication cables.
This means that while American Pulverizer Co. thought they were saving a few dollars by NOT installing the mandatory grounding, they may have actually been costing themselves big dollars in data system losses. Companies that have gone through the process of installing effective chassis grounding systems, inevitably report lower maintenance costs and reduced down-time. These companies are often shocked to find that after installing their grounding system, they no longer have to purchase very expensive replacement cards for their electronic systems, and that troublesome equipment all of a sudden starts working properly, and power outages and breaker failures come to an end. If American Pulverizer Co. had installed the mandatory grounding system in 2006, they probably would have been saving $121,100.00 a year in lower maintenance costs!
Hopefully, after OSHA forces American Pulverizer Co. to install the mandatory grounding system, they will find that their lower maintenance costs and improved downtime pays for the expense within the year. It will be a hard lesson to learn, particularly given that they could have been saving that money for the last 5-years instead of spending it, but sometimes it takes a forceful nudge in the right direction to see the long-term benefits of proper electrical grounding.
Article by: David Stockin, August 19, 2011
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