There is a growing realization in industrial circles that companies will need to invest significant dollars in electrical safety during the next few years. Many plant managers are discovering that the electrical infrastructure, power generating equipment and work procedures have not been thoroughly evaluated for electrical safety since the doors were opened. Over time, electrical infrastructure has changed, facilities have expanded, load requirements have increased and equipment may have degraded with age or lack of maintenance. Electrical systems that were appropriate for the loads and incoming power when they were installed may now expose employees to life-threatening hazards.
This realization is leading industry to a paradigm shift: We can no longer treat electrical distribution systems as everlasting, never-changing components of a facility. Instead, we must consider the electrical infrastructure a dynamic system that requires regular attention and a formal preventive maintenance program. It must be constantly maintained and re-evaluated for proper loading, short-circuit sizing and equipment performance.
A major force behind the culture shift is government mandates. Regulations and standards such as OSHA and NFPA 70E are forcing plant managers to be proactive about electrical hazards. Companies that fail to comply face severe fines from OSHA, in addition to costly downtime and loss of production from accidents. The wise course is to address safety issues before there is an incident.
OSHA drives change
Progressive companies already are preventing future problems by adopting OSHA, NFPA 70E, NEC and NEMA standards and guidelines in their internal processes. They are instituting equipment preventive maintenance programs, circuit-breaker maintenance programs and electrical safety programs that describe detailed electrical requirements.
Subpart S of OSHA Standard 29 CFR 1910 (OSHA 1910) addresses electrical safety requirements, including design, work practices, maintenance requirements and special equipment. It requires all electrical hazards to be identified to determine their severity and what personal protective equipment (PPE) and safe work practices may be required to protect workers.
Many plant and electrical maintenance managers mistakenly assume this means simply performing an arc-flash hazard assessment. In practical terms, it requires an assessment of the entire electrical system to identify all hazards, not just for arc-flash but for shock and potential equipment deficiencies. It also requires companies to establish and document safe work practices, properly train their personnel to identify and avoid hazards, and select and use proper PPE.
In fully implementing OSHA 1910 Subpart S, plant managers are beginning to realize that they may have not have been following proper procedures since the facility was built. It is estimated that less than 10% of plants even have up-to-date, one-line electrical drawings. It will take a great deal of work just to come up with correct drawings and then identify the potential hazards. Once the hazards are identified, they must be corrected or minimized.
Electrical hazard assessments
Plant managers should brace themselves: The required assessment work is detailed and possibly costly. It includes calculating the potential energy available for an arc-flash, labeling equipment to meet NEC requirements and purchasing the correct PPE.
It includes analyzing all available short-circuit power sources and determining the short-circuit withstand ratings of all parts — from the wiring to the protective devices. Then it requires finding out if everything is operating correctly and if existing overcurrent protection devices are still appropriate and still work. This may require actual testing rather than just calculations.
When faced with the prospect of performing an initial hazard assessment, plant managers usually learn quickly that they are not staffed to perform the study in-house. Companies must find a firm capable of performing an in-depth analysis that determines all hazards and their causes. The most cost-effective approach is to hire a professional electrical engineering consultant or electrical safety service organization that specializes in OSHA compliance, NEC and NFPA 70E electrical safety analysis and worker training.
It doesn’t stop there. Once any electrical system deficiencies and hazards have been identified, plants must take corrective actions. Some equipment will have to be repaired or reconditioned and some replaced. Maintenance workers will have to be trained to recognize and avoid all remaining hazards — and OSHA 1910 expects this training for both qualified and nonqualified workers. Finally, companies will have to document equipment history in an asset library and create a program to institute preventive maintenance, reliability inspections, testing, recalibration and re-certifications.
Safety takes ongoing maintenance
The time is coming when an electrical hazard assessment will be an ongoing function of plant maintenance. Standards will most likely require that arc flash studies be updated as changes are made in the facility’s electrical system. Other engineering studies such as short-circuit and coordination studies should also be reassessed on a regular basis. To meet safety requirements, all facilities should keep their one-line electrical drawings well documented and updated. When changes are made, the system must be reanalyzed to assess the impact to previously determined hazard levels.
Ongoing assessments may be costly, but the cost of not doing anything may be someone’s life or a company being put out of business.
The coming paradigm shift in electrical safety parallels the shift to preventive maintenance in the last century. If a motor fails, the plant manager wants to know the root cause to prevent future failures and remove the cost. The same is true for electrical hazards: By understanding and proactively maintaining the electrical infrastructure, plants will minimize electrical system failures and ultimately reduce downtime and operational, medical and liability costs.
Larry Altmayer is POWR-GARD services manager for Littelfuse Inc., Des Plaines, Ill.