The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Electrical professionals working on the installation, construction, repair and maintenance of facilities are exposed to the risk of electric shock due to their possible interaction with live parts, but also due to the contact with the enclosure of equipment, normally not energized, which has become live under fault conditions. This necessary interaction with equipment for its intended use can, therefore,...
Often overlooked in a company's Electrical Safety Program is the need to audit the Electrical Safety Program and the implemented preventive and protective control measures to mitigate or reduce the risk of exposure to workers to the electrical hazards of arc flash and shock to as low as reasonably practicable (ALARP). Findings from Electrical Safety Audits provide evidence and measurable results to...
The performance of electrical systems depends on, among other things, the type and quality of maintenance and the safe operation of the equipment. It is necessary to evaluate the quality of the maintenance and safety procedures utilized within the safe work practice program. The paper advises the use of external auditing of electrical systems and maintenance programs for the advantages it brings to...
A common practice is to install a service disconnect or a main disconnect for a feeder system in the same enclosure compartment as the downstream overcurrent protective devices. This can result in potential safety risks of shock and arc flash.
A new contractor is signed on to perform electrical work. The corporate environmental health and safety verification process is complete. The terms, conditions and other commercial terms are in place between both organizations. Now, as the host company's representative, the next most important step in the process begins: qualify the individual electrical workers prior to them entering work site. Poor...
A Change Agent understands that their job is not done when their Electrical Safety Program (“ESP”) is approved and funded; in fact their job has just begun.
The results of experimental arc testing of a nontreated cotton T-shirt with three different geometrical arc electrode arrangements are presented and discussed. Different geometries of arc electrodes result in different electromagnetic interactions of an arc current with current flowing between arc electrodes that in turn cause very different arc behavior. Ignition threshold of a T-shirt was determined...
Occupational Health & Safety Management System (OHSMS) Standards such as ANSI Z10 provide a framework for an employer to manage and continuously improve occupational health and safety performance.
Although Class A Ground-Fault Circuit Interrupters (GFCIs) have been responsible for a substantial reduction in residential electrocutions, their limitation on system voltage (maximum 240 V) and their maximum allowable leakage current of 6 mA make them impractical for 480 or 600 V industrial power systems. UL 943C defines special-purpose GFCIs that can be used on systems up to 600 V and allow for...
This case study is based on an arc flash incident that occurred at a pellet plant facility located in Port-Cartier, Québec, Canada. The incident occurred while replacing a 2000A 600V MCC main molded breaker by a more recent model, as recommended by our technical service. One of the causes of this arc flash incident was the temporary protective ground that didn't withstand the short circuit current...
This paper explores uses for and explains the specifications of the ASTM standard, ASTM F2677-08a Standard Specification for Electrically Insulating Aprons Applications. This newer standard was listed in NFPA 70E in 2012 but has no guidance on how and when these aprons and other garments which could be designed using the standard are to be used in the field. Some shocks occur to parts of the body...
This paper discusses some key audit methods and questions used to evaluate worker behaviors and adherence to corporate electrical safe work standards. This research was prompted by the question: “Are the approaches used and the questions asked during an audit really uncovering all aspects of worker behavior?” Human factors play a significant role in both getting accurate responses from workers during...
Having good procedures in place and having safe equipment are just two of the elements that are needed in having a good electrical safety program. People are the third element. People do not automatically, instinctively or intuitively follow the safe work practices contained in electrical safety procedures. They need to be led. How we lead and encourage people to be aware of the electrical hazards...
In February 2011, construction had just begun on a planned electrical safety improvements project at the East Bay Municipal Utility District's Walnut Creek Raw Water Pumping Plants (WCPP Nos. 1&2) when the electrical substation powering the facility was destroyed by a fault. This was followed a month later by a flood that completely filled the building that houses WCPP Nos. 1&2, submerging...
This paper will discuss potential safety issues of lighting in an industrial setting. We will explore lighting safety factors that help mitigate such safety concerns. The paper will highlight lighting design, maintenance, location, installation, maintenance ergonomics, and hazardous location concerns for lighting systems. The goal of this paper is to assist end users during their design, operation,...
It is widely acknowledged that an arc flash hazard may exist when energized conductors are within equipment in an enclosed condition if a person is interacting with the equipment at close proximity in such a manner that could cause an electric arc fault. This paper presents the results of scouting tests of arc flash events within enclosed low voltage equipment (internal arc faults). This testing was...
Equipment design and installation can account for a major arc flash incident. Having the correct phase barriers in place to shield fuses, contactors, buswork, etc… can save you time and money. This paper discusses an incident our company had involving the installation of a new Medium Voltage Motor Control Center (MCC). There were no phase barriers installed between the section of bus that connects...
In past decades, many efforts have been given to improving the Residual Current Device (RCD) that has been the major and only means for electrocution protection since 1955. However, all of those efforts are based on the principle of RCDs, which are no longer in accordance with modern appliance usage, and in many cases RCDs may cause nuisance trips or fail to work. This paper proposes an innovative...
A Maintenance Mechanic received a serous electric shock troubleshooting a small acid pump. Investigation revealed incorrect motor connection by a “Qualified Person”. So why did the electrician, with over 20 years' experience, known to be Qualified, responsible, proficient and who constantly maintained focus on safety, make such a mistake?
It is typical for personnel using electric welders to use two leads, an electrode lead and a ground lead. This paper will review the use of the ground lead, rename it as a “work” lead, redefine the term “ground” lead, and recommend how to use this new “ground” lead.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.