Arc Flash & Electrical Safety

Electric Power Conference

Steve Hudgik — Wed, 07 May 2008 17:30:00 +0000

Joseph Deane is principal owner of KTR Associates, spoke about arc flash at the Electric Power Conference this morning. Mr. Deane has over 25 years of experience as an Electrical Engineer, Project Manager, and Executive, working in both the industrial and utility business sectors.

The following is an abstract of his presentation:

The NFPA 70E standard was created at the request of OSHA in 1979 to recognize the difference between design and workplace safety. The National Electric Code (NEC) provides the installation (design) standard while the NFPA 70E is the workplace safety standard.

NFPA 70E describes employer responsibilities and recommendations on topics such as employee training, safety-related work practices, tagout procedures, calculating flash protection boundaries and PPE requirements. The current standard recognizes arc flash as a serious hazard and establishes PPE requirements that apply when working around energized equipment.

Why is the NFPA-70E Standard Important? Because following the NFPA-70E standard may save a life. Hazardous arc flashes can occur in any electrical device in which energy is high enough to sustain an arc. The heat exposure due to an electrical arc can produce first-degree burns, permanent blindness, or even death.

In an effort to reduce the extent of potential injuries NFPA-70E specifies boundaries within which flash protection (PPE) is required.

The National Safety Council estimates that an average of more than one fatality a day occurs while working around electrical equipment. Of these fatalities, more than half occurred while working on energized equipment rated 600 volts or below. In addition, five to ten electrical “arc flashes” occur in the workplace everyday. The medical costs for an individually exposed to an electrical arc flash is around $12 to $20 million.

Employers need to include both shock and arc hazard identification in their safety programs.

When working on electrical apparatus (switchgear, panelboards, motor control centers, etc.) the incident energy or available fault current to produce an arc flash needs to be clearly identified on each respective enclosure or piece of electrical equipment. As a part of that label, when employees must work within the flash protection boundary, it is important to include the incident energy. Producing a Flash Hazard Analysis can do this.

Does OSHA recognize the NFPA 70E? Absolutely. OSHA has recently updated their electrical standards to reflect the latest in both the NEC and NFPA 70E standard. OSHA will cite companies for non-compliance with 29 CFR 1910.335(a)(1)(i) which requires the use of protective equipment when working where a potential hazard exists and 29 CFR 1910.132(d)(1) which requires the employer to provide an assessment of the workplace for hazards and the need for personal protective equipment.

OSHA also utilizes the “General Duty Clause” which states, "each employer shall furnish to each of its employees a place of employment that is free from recognized hazards that are likely to cause death or serious physical harm."

NIOSH Arc Flash Videos

Steve Hudgik — Mon, 05 May 2008 15:48:00 +0000

NIOSH has produced an arc flash awareness video. You can review part of the video below. Below that there is a link to a second part of the video, which is available on YouTube. You can download the complete NIOSH arc flash awareness video from their video page at: http://cdc.gov/Niosh/mining/products/product152.htm

Part two on YouTube: http://www.youtube.com/watch?v=cDGxyZoxWOg

OSHA Cites DCS Sanitation Management Inc. Following Electrocution Death

Steve Hudgik — Tue, 15 Apr 2008 14:35:00 +0000

The following is a press release from OSHA dated April 14, 2008.

OSHA cites DCS Sanitation Management Inc. for multiple safety and health violations following an electrocution death.

KANSAS CITY, Mo. -- The U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) has cited DCS Sanitation Management Inc. for 10 alleged violations of federal safety and health standards following the Oct. 12, 2007, death of an employee at a Springfield, Mo., poultry processing facility.

An employee of Cincinnati, Ohio-based DCS Sanitation Management, working to sanitize poultry processing equipment, was electrocuted when the equipment's conductive surface became energized.

"Our inspection revealed multiple violations of OSHA's electrical standards," said Charles E. Adkins, OSHA's regional administrator in Kansas City. "It is imperative that employers remain committed to keeping the workplace safe at all times."

An alleged willful violation addresses hazards associated with the company's failure to ensure employees are removed from equipment hazard areas, all tools are removed, and equipment is operationally intact prior to its release from lockout/tagout safeguards and employee use. Lockout/tagout refers to preventing accidental start-up of machinery during maintenance. Willful violations are those committed with an intentional disregard of, or plain indifference to, the requirements of the Occupational Safety and Health Act and regulations.

An alleged repeat violation addresses a hazard associated with the lack of suitable facilities for quick drenching and/or flushing of the eyes and body in the event of an emergency when employees were working with injurious corrosives. Repeat violations are issued when an employer previously has been cited for the same, or a substantially similar, violation that has become a final order.

Alleged serious violations address the following hazards: failure to ensure electrical equipment was free from recognized hazards; failure to ensure the means of grounding machines and equipment was continuous and effective; enclosures for electrical components in wet environments that were not waterproof; failure to provide all flexible cords with a strain relief; failure to provide a standard guardrail system for every floor opening or platform above dangerous equipment; failure to provide and/or require the use of appropriate eye and face protective equipment; and allowing the consumption of food and beverages in areas exposed to toxic chemicals.

An other-than-serious violation addresses the employer's failure to report the fatal accident to the nearest OSHA area office within the required eight hours of occurrence. The agency's proposed penalties for all violations total $124,500.

DCS Sanitation Management Inc. has 15 business days from receipt of the citations and proposed penalties to comply, request and participate in an informal conference with OSHA's area director, or contest the citations and penalties before the independent Occupational Safety and Health Review Commission.

Failing To Follow Safety Rules

Steve Hudgik — Mon, 14 Apr 2008 14:18:00 +0000

Sometimes we've done the same thing over and over so many times we start to feel like we can "get away with" taking shortcuts. This video is a dramatization that shows what can happen when we fail to follow elementary electrical safety rules.

University Employees Injured By Arc Flash

Steve Hudgik — Thu, 10 Apr 2008 13:53:00 +0000

The Texas Christian University Daily Skiff (the student newspaper) reports in today's edition that two university employees were injured by an arc flash. The article reports that:

"Two physical plant employees were injured Wednesday morning in an electrical accident in the basement of Tandy Hall, university officials said."

"One employee who suffered injuries to his eyes and forearm was still in the hospital late Wednesday, and the other, who injured his knee while moving to avoid the shock, was treated and released, said Tracy Syler-Jones, associate vice chancellor for marketing and communication."

There had been a power outage and the two employees were working to start a backup generator. This incident should make us aware that we must always be alert to the possibility of an arc flash when working with electrical equipment. My guess is that the two workers who were injured never even considered the possibility of an arc flash. Training, proper labeling, and the use of PPE are three pillars that can not be ignored or forgotten.

Solving The Puzzle Of Electrical Safety Compliance

Steve Hudgik — Wed, 09 Apr 2008 21:19:00 +0000

Square D Schneider Electric has released another video on their website which is also available for online viewing or download. The new video is called "Solving the Puzzle of Electrical Safety Compliance".

This new video provides a basic seminar about electrical safety compliance which thoroughly explains the details about electrical hazards and NFPA 70E, and how OSHA enforces this important electrical safety standard. The non-technical treatment is suitable for anyone who is responsible for, or concerned with electrical safety.

The running time for this video is approximately 75 minutes. It is available in four formats (two for streaming video and two for download). Each option has two file sizes to accommodate different internet connection speeds. Because the video length is 75 minutes, you may prefer to use one of the two download options that are available. Download will take several minutes to complete, depending on your internet connection quality.

Honeywell Aquires Arc Flash Protective Equipment Maker

Steve Hudgik — Mon, 07 Apr 2008 14:20:00 +0000

The following is a press release from Honeywell:

Honeywell Signs Definitive Agreement to Acquire Norcross Safety Products

MORRIS TOWNSHIP, N.J. – Honeywell on Friday announced a definitive agreement to acquire Norcross Safety Products L.L.C., a leading manufacturer of Personal Protective Equipment (PPE), for approximately $1.2 billion.

Norcross, based in Oak Brook, IL, and majority owned by Odyssey Investment Partners, manufactures a wide range of protective and safety equipment for the fire service, utility and general industrial worker segments. The agreement is subject to customary closing conditions, including regulatory review. Norcross will be integrated into Honeywell Life Safety, part of Honeywell’s Automation and Control Solutions (ACS) group. Norcross’s revenue was approximately $609 million in 2007.

“From emergency responders, to electrical workers to the industrial workforce, Norcross’s innovative solutions protect those who work in environments where safety protection is paramount,” said Roger Fradin, President and CEO of Honeywell ACS. “With more than 100 years of industry experience, best-in-class solutions and trusted brands, and a strong management team with exceptional talent and depth, Norcross is a globally recognized industry leader that will bolster our offerings to our customers in key Life Safety segments.”

Fradin continued, “This acquisition provides Honeywell with a complete platform in a fragmented, global segment which is expected to yield substantial growth opportunities. Investing in Norcross allows Honeywell to fully participate in the broad and highly regulated industrial safety marketplace.”

As one of the industry’s largest providers of personal protective equipment, Norcross has a unique ability to provide integrated head-to-toe protective equipment solutions. Norcross is a recognized leader in a number of market segments including Air Purifying Respirators (APRs), protective footwear, protective headgear, firefighter turnout gear, high-voltage sleeves and gloves, and arc flash protection. It benefits from one of the industry’s most extensive distribution networks with more than 2,500 distributors.

“This acquisition creates an exciting adjacency for Honeywell Life Safety – especially our Fire Systems and Gas Detection businesses, which share common distribution channels with Norcross. We expect strong sales synergies across Honeywell businesses and opportunities to add value to Norcross products with Honeywell electronic gas sensors, fire detection and advanced fiber material technologies,” said Mark Levy, President of Honeywell Life Safety. “Norcross and its leadership in the personal protection segment are highly complementary to our portfolio and customer base. The acquisition of Norcross builds on the highly successful Novar, Zellweger and First Technology acquisitions and extends our already strong position in the $20 billion global Life Safety marketplace.”

Norcross is uniquely positioned in a number of core vertical segments including General Safety and Preparedness (respiratory protection; protective footwear; hand protection; eye, head, face and ear protection; first aid; and fall protection); Fire Service (firefighter turnout gear, footwear, helmets, gloves and other accessories); and Electrical Safety (gloves and sleeves, lineman equipment and arc flash protection). Norcross sells its products under trusted, long-standing and well-recognized brand names, including North, KCL, Fibre-Metal, Morning Pride, Pro-Warrington, Salisbury and Servus.

“Becoming a part of Honeywell is a terrific opportunity for our business, customers and employees. We are enthusiastic that this acquisition brings us access to even stronger technologies, global distribution channels, and gives us the ability to expand our product offerings in a world with heightened safety demands,” said Bob Peterson, President and CEO of Norcross Safety Products.

Honeywell International is a $36 billion diversified technology and manufacturing leader, serving customers worldwide with aerospace products and services; control technologies for buildings, homes and industry; automotive products; turbochargers; and specialty materials. Based in Morris Township, N.J., Honeywell’s shares are traded on the New York, London and Chicago Stock Exchanges. For additional information, please visit www.honeywell.com.

Contractors Cited by OSHA Following Electrocution Death At Maine Jobsite

Steve Hudgik — Thu, 27 Mar 2008 16:24:00 +0000

The U.S. Department of Labor's Occupational Safety and Health Administration (OSHA) has cited two contractors - J&S Carpentry of Columbia, Maine, and Irving Equipment Inc. of Hampton, N.H. - for 15 alleged violations of safety standards following the electrocution death of an employee at a Hermon, Maine, residential construction site.

On Sept. 12, 2007, an Irving crane contacted an energized 7,200 volt overhead power line as two J&S Carpentry employees were attempting to attach the crane's rigging equipment to a section of a modular home that was being constructed at 28 Lily Lane in Hermon. One of the employees was killed and the other seriously injured by the electric current.

OSHA's inspection found that the crane was being operated within 10 feet of the power line, which had not been de-energized beforehand, as required. The two contractors face a combined total of $121,500 in proposed fines.

"The basic safeguards designed to prevent just this sort of accident were ignored here, with fatal results," said William Coffin, OSHA's area director for Maine. "De-energizing the power line and maintaining a safe working distance from it would have prevented this death and injury."

J&S Carpentry, for whom the employees worked, was issued two willful citations for allowing employees to work in close proximity to the energized power line and for not protecting employees against fall hazards. OSHA also issued the company four serious citations for a lack of on-site medical attention; absence of hardhats and electrical warning signs; and ladder hazards. J&S Carpentry faces a total of $32,000 in proposed fines for these conditions.

Irving Equipment, which owned and operated the crane, has been issued three repeat citations for operating the crane in high winds, inadequate support for the crane's outriggers, and not inspecting the job site to identify and correct these and other hazards. OSHA had cited the company in May 2005 for similar hazards at a Freeport, Maine, job site.

Irving Equipment also has been issued six serious citations for operating the crane within 10 feet of the power line; not operating the crane in accordance with the manufacturer's specifications and industry standards; and lack of fall protection, hardhats, on-site medical attention and an electrical warning sign. Irving Equipment faces a total of $89,500 in proposed fines for these conditions.

OSHA defines a willful violation as one committed with plain indifference to or intentional disregard for employee safety and health. A serious citation is issued when death or serious physical harm is likely to result from a hazard about which the employer knew or should have known.

Each company has 15 business days from receipt of its citations to contest them before the independent Occupational Safety and Health Review Commission. The inspection was conducted by OSHA's Bangor District Office.

What OSHA Expects: The Electrical Safety Questions OSHA Will Ask

Steve Hudgik — Fri, 14 Mar 2008 13:40:00 +0000

This article, What OSHA Expects: The Electrical Safety Questions OSHA Will Ask During an Investigation by Kenneth Cybart appeared in yesterday's Occupational Hazards Magazine. This is how the article introduces itself:

"Wouldn’t it be nice to know exactly what OSHA is training its inspectors to look for during an inspection that includes electrical safety, including surprising new areas of emphasis based on national OSHA directives? This article covers some of the typical electrical safety questions that OSHA inspectors will ask during a field investigation, what they mean and how to be prepared and in compliance."

The article looks at 17 questions OSHA inspectors will ask, such as:

Is there a description of the circuit or equipment at the job location?

Is there a detailed job description of planned work?

Can you justify why equipment cannot be de-energized or the job deferred until the next scheduled outage?

Has a detailed work procedure been established?

You can read the complete article, including all 17 questions, on Occupational Hazards' web site.

Avoiding Five Big Mistakes

Steve Hudgik — Wed, 12 Mar 2008 22:47:00 +0000

An article by Larry Altmayer (Services Manager for POWR-GARD, Littlefuse, Inc.) in this month's issue of Facility Safety discusses Avoiding Five Big Mistakes when assessing your facility for electrical hazards.

The articles opens by describing this problem:

"In one case, a manager didn’t calculate Arc flash hazards because a consultant told him the power serving that part of his plant was too low to cause an arc flash. He didn’t realize that low-level faults can cause a circuit breaker or fuse to open more slowly and actually increase the heat energy during an arc-flash. He had good intentions, but the plant was out of compliance by not identifying real hazards and his workers were at risk."

The five big mistakes are identified as:

1.Conducting an incomplete assessment.
2. Using the NFPA 70E Table Method improperly.
3. Trying to do an assessment with in-house staff.
4. Not correcting deficiencies after the assessment.
5. Not changing work procedures after the assessment.

You can read the entire article on the Facility Safety web site.

WE Energies To Pay Damages In Plant Accident

Steve Hudgik — Wed, 12 Mar 2008 13:30:00 +0000

The Milwaukee Journal Sentinel reports today on the court judgment resulting from an arc flash injury at the Patrick Cudahy meat packing plant.

The article reports that Neil Wolf was injured by an arc flash on May 26, 2003, at the Patrick Cudahy plant. The jury awarded $515,000 to Mr. Wolf.

WE Energies, the local power company, was found to be 37% negligent and will have to pay $190,550 of the award.

Patrick Cudahy was found to be 55% responsible. But because Patrick Cudahy was a plaintiff, not a defendant in this case, they will not need to pay any of the jury award.

Mr. Wolf was found to be 10% responsible.

You can read the Milwaukee Journal Sentinel article at: http://www.jsonline.com/story/index.aspx?id=727274

OSHA imposed $148,500 in fines in December 2004. The following is what OSHA reported at that time:

"Three workers were reported to have been troubleshooting electrical switchgear at the Cudahy, Wis., facility when electricity arched and exploded. OSHA's investigation revealed that the three workers, all of whom received first, second and third degree burns throughout their bodies, were not using insulated tools, were not wearing proper personal protective equipment, and were not following appropriate safety standards. OSHA issued willful and serious violations to Cudahy for allegedly failing to provide such equipment, and warning or training the workers about flash hazards."

Victims Of Arc Flash

Steve Hudgik — Tue, 26 Feb 2008 15:42:00 +0000

The statistics say that 10 people a day are injured by arc flash. More and more of these people are telling their stories using video. I'm finding new videos on a regular basis. In the following video a man and his wife tell the story of his injury as a result of an arc flash. It is called "Arc Flash - Survival or Prevention. The David Bird Story."

Why are so many videos about arc flash showing up on the internet? My guess is because arc flash injuries are so sudden and unexpected, and the consequences are serious. The key word here is "unexpected". Arc flash hazards have been ignored until recently. Most equipment that presents an arc flash hazard is not even properly labeled. Workers have not had arc flash safety training.

This is a safety hazard that can not be ignored any longer.

Paradigm Shift Requires Look At Plant Electrical Infrastructure

Steve Hudgik — Thu, 21 Feb 2008 14:57:00 +0000

An article by Larry Altmayer, POWR-GARD Services Manager for Littelfuse Inc. in the online edition of Plant Services magazine talks about how we need to change our view of electrical distribution systems. The article opens by stating:

"No longer can maintenance treat electrical distribution systems as everlasting, never-changing components of a facility. Instead, we must consider the electrical infrastructure as a dynamic system that requires regular attention and a formal preventive maintenance program."

The article makes the point that electrical systems can no longer be viewed as unchanging, static systems that can be installed and forgotten. They are dynamic systems that are changing to meet continually changing needs, and as a result must be regularly re-evaluated and maintained.

Mr. Altmayer then covers how OSHA, NFPA 70E, NEC and NEMA codes and standards are driving change and this results in a need for current electrical hazard assessments and ongoing maintenance. Overall this article provides a good overview of a dynamic situation that we all need to address.

You can read the complete article at: http://www.plantservices.com/articles/2008/034.html

Arc Flash Evolution

Steve Hudgik — Tue, 12 Feb 2008 18:36:00 +0000

An article titled "Arc Flash Evolution" was included in the December issue of Control Engineering magazine.

"It seemed safe enough. The industrial electricians were just going to take a few measurements prior to starting the job. Everything was energized, but that should have been OK, because the electricians were going to be a safe distance away."

"They were. The metal tip of their wooden yardstick wasn't. The resulting arc appeared and vanished in less than a second, sticking around long enough to catch clothes on fire. The unlucky electricians joined the estimated hundreds of arc-flash injuries a year that require hospitalization. Their co-worker standing 10 feet away became one of the thousands who annually suffer injuries that don't require a hospital stay."

The article goes on to discuss arc flash warning labels, bolted vs. arcing faults and tripping devices used to limit the severity of arc flash. At the end of the article it refers to a video of a one hour arc flash webinar called "Arc Flash Hazard: Understanding Safe Electrical Work Practices, Standards and Regulations". The video can be viewed after going through a short registration process. Although I was not able to view the video, as I got a blank screen after registering. This may be the result of the network security we have in place. However, the article on its own is worth reading.

Voltage Indicators Enhance Safety

Steve Hudgik — Mon, 11 Feb 2008 20:00:00 +0000

The "Near-death experiences among paper mill electricians are all too common. On this particular day, a combination circuit breaker/welding outlet failed to provide power to the welder. The maintenance electrician began to replace the outlet. Casually, his co-worker paused and said, 'Better check it with a meter.' The meter revealed that one phase of the circuit breaker had failed 'live' leaving the outlet energized. For these guys, this near-death experience is permanently imprinted on their minds in vivid 'Technicolor' detail never to be forgotten."

The article goes on to describe various methods of detecting voltage, and how voltage indicators and volt meters "are on the same team with their own unique safety benefits."

No author for the article is listed, but it appears to have come from Grace Engineered Products, Inc.

Compliance Takes More Than A Label

Steve Hudgik — Wed, 23 Jan 2008 17:45:00 +0000

An article by Chet Davis, originally published in the November 2005 issue of Plant Engineering Magazine, was republished by Facility Safety Management magazine this month (January 2008). It is called, Compliance Takes More Than A Label. Over two years have passed and the message is still relevant. A key point made by the article is:

"The current arc-flash phenomenon appears to be operating on fear rather than principle. The fear is massive lawsuits and OSHA fines if an accident does occur rather than a sound reasoning as to why a safety culture makes good business sense in daily operations. While it may have taken some fear in the initial movement to motivate companies toward implementing safety standards, if the safety aspect of arcflash is limited to labeling and PPE requirements, the inclination will soon wear off."

From what I've observed, the "inclination" in many cases has not yet worn off. Putting the safety of people first should always be the goal. Safety does not end with applying a warning label. Proper labeling is a critical, and important first step, but establishing an ingrained safety culture is key.

For example, many of the arc flash labels I've seen just list the arc flash boundaries... and they run it all together in a paragraph of text in the center of the label. The information is inadequate and the presentation is unreadable. For a label to be effective it must have complete information, presented in an easy-to-read format. In addition to boundary information an arc flash label should clearly show the required PPE.

The Graphic Product's Arc Flash Labeling Best Practices points out another piece of important information that should be on the label:

"Although labeling is important, the best way to prevent electrical injuries is to de-energize the equipment and use LOTO. Identifying the available upstream lockable point on the label helps enforce LOTO. By Identifying the first disconnect feeding the equipment, LOTO is reinforced and workers are reminded to use LOTO procedures."

New Arc Flash Labeling Best Pactices Guide Available Free

Steve Hudgik — Tue, 15 Jan 2008 17:12:00 +0000

A new best practices labeling guide from Graphic Products provides a concise summary of arc flash labeling requirements. Starting with a facility inspection, the guide provides a comprehensive description of what is needed to ensure there is proper arc flash labeling throughout a facility.

The following is the Table of Contents for this best practices guide:

Required Tools
Definitions
....What is Arc Flash?
....Definitions of Terms
Evaluation - Facility Inspection
Label Creation
....What Information Should Be Included On An Arc Flash Label?
....Needed Equipment and Supplies
....Label Creation Steps
....Label Creation Using Die-Cut Labels
....Label Creation Using Continuous Vinyl
Label Placement
....Locations Where Labels Should Be Placed
....Removing Old Labels
Label Maintenance
One Page Arc Flash Hazard Labeling Guide

The Arc Flash Best Practices Guide may be downloaded free.

Square D Electrical Safety Video

Steve Hudgik — Fri, 04 Jan 2008 16:04:00 +0000

I've featured many videos on this blog. A problem has been that, no matter how good the video, since they came from YouTube many people could not use them. Square D has produced an excellent electrical safety video that is available for downloading. This means you can put this video on any computer and show it anywhere you need to do electrical safety training.

All that is required is a short registration process.

Use this link to go to the registration/download page.

This video covers electrical safety in general, with a heavy emphasis on arc flash safety. A dramatic video of an arc flash explosion demonstrates the effectiveness of PPE and how serious arc flash injuries can be.

Top Safety Story of 2007

Steve Hudgik — Fri, 21 Dec 2007 15:30:00 +0000

Occupational Hazards E-News has put out their list of the top ten most read news stories on their web site in 2007. The #1 most read story was about OSHA issuing a final rule on electrical standards.

Here is the February 13th press release from OSHA:

OSHA Issues Final Rule on Electrical Installation Standard

WASHINGTON -- The Occupational Safety and Health Administration will publish a final rule in tomorrow's Federal Register for an updated electrical installation standard.

"These are the first changes to the electrical installation requirements in 25 years, so it is important the standard reflects the most current practices and technologies in the industry," said Assistant Secretary for Occupational Safety and Health Edwin G. Foulke Jr. "The revised standard strengthens employee protections and adds consistency between OSHA's requirements and many state and local building codes which have adopted updated National Fire Protection Association (NFPA) and National Electrical Code provisions."

Changes to OSHA's general industry electrical installation standard focus on safety in the design and installation of electric equipment in the workplace. The updated standard includes a new alternative method for classifying and installing equipment in Class I hazardous locations; new requirements for ground-fault circuit interrupters (GFCIs) and new provisions on wiring for carnivals and similar installations.

The final rule updates the general industry electrical installation requirements to the 2000 edition of the NFPA 70E, which was used as the foundation of the revised standard. The final rule also replaces the reference to the 1971 National Electrical Code in the mandatory appendix to the powered platform standard with a reference to OSHA's electrical installation standard.

Under the Occupational Safety and Health Act of 1970, employers are responsible for providing a safe and healthful workplace for their employees. OSHA's role is to assure the safety and health of America's working men and women by setting and enforcing standards; providing training, outreach, and education; establishing partnerships; and encouraging continual process improvement in workplace safety and health. For more information, visit www.osha.gov.

Isolating the Risk of Catastrophic Arc Flash Explosions

Steve Hudgik — Wed, 19 Dec 2007 17:41:00 +0000

Betty Jackson, of Hoffman, has publish a white paper titled "Isolating the Risk of Catastrophic Arc Flash Explosions" that is available online. This paper makes that point that arc flash incidents will happen and that a solution is the Hoffman SEQUESTR™ External Disconnect Enclosure.

The paper begins by providing an overview of arc flash, its causes and the damage that can result. It gives this summary of arc flash hazards:

"According to NFPA 70E Standard for Electrical Safety in the Workplace, 2004 Edition, pages 12 and 28, the two most important numbers to remember are 1.2 and 40. Incident energy levels greater than 1.2 calories per centimeter-squared can produce second degree burns. The NFPA 70E requires that workers wear personal protective equipment (PPE) when working with 50 volts or more. Arc flash levels above 40 calories per centimeter squared can be fatal and usually result in a massive pressurized blast with sound pressure waves and projectiles. The PPE is available for exposures up to 100 calories per centimeter-squared; however, the force from the pressurized blast can be fatal regardless of the PPE."

The white paper then goes on to point out that in spite of best efforts, because of the large number of variables--some of which may be unknown--the true extent of the arc flash hazard can never be known. In addition, the paper points out something I know to be true from personal experience:

"During private discussions, electrical engineers have revealed that, despite their compliance training, they sometimes skirt the PPE rules because the bulky, fire retardant suit, gloves, face shield/goggles and other gear is hot, uncomfortable and makes service and maintenance time-consuming and cumbersome."

The second half of the white paper dicusses the SEQUESTR™ External Disconnect Enclosure.

"The SEQUESTR™ External Disconnect Enclosure attaches to the side of a main control enclosure and houses only the disconnect switch or circuit breaker, physically removing it from the main enclosure."

"Live power is no longer present in the main control enclosure when power is turned off at the disconnect switch. It completely shuts down the power in the main cabinet, and there is no hazard of power coming into the box. Its system also interlocks the doors of the main control cabinet when the disconnect switch is powered on. This allows users to comply with the disconnect door interlocking requirements of UL 508A, NFPA79, IEC 60204, and HS 1738, the most common electrical standards for industrial machinery."

Use the link above to read the entire white paper.

Free Online Electrical Formulas

Steve Hudgik — Wed, 19 Dec 2007 17:07:00 +0000

The following web sites provide general purpose electrical formulas and information:

Search Electrical provides a range of electrical formulas and resources available as Excel spreadsheets or PDF files. They include an Arc Blast Calculator available as an Excel spreadsheet. A Fault Current spreadsheet and planning documents. Plus there are links to free online conversion utilities and other resources.

MC² is a company that provides estimating services for contractors. They provide a page with electrical formulas for estimators. The following formulas are provided: AMPERES when KVA is known; AMPERES when horsepower is known; AMPERES when kilowatts are known; KILOWATTS; KILOVOLT/AMPERES; HORSEPOWER and WATTS.

ConWeb provides a variety of technical tables, including Electrical & Mechanical Formulas . These include: OHMS Law; Power - AC Circuits; Power - DC Circuits; and formulas for fan, blower and pump motors.

BOWest Party, Ltd. - Electrical & Project Engineering has a library with a wide variety of electrical information and formulas such as Electrical Circuit Theorems; Electical Circuit Formulas; and Electrical System Formulas. All of the formulas are indexed at the bottom of their page.

The Myths and Realities of Arc Flash Protection

Steve Hudgik — Thu, 13 Dec 2007 23:40:00 +0000

Electric Energy Online has an excellent article that is mostly about Personal Protective Equipment (PPE) used for arc flash protection. It discusses 10 myths about arc flash.

MYTH 1: Arc Flash explosions do not happen… I have never seen one.
MYTH 2: There is nothing anyone can do to protect against an Arc Flash explosion
MYTH 3: Will Street Clothes made of cotton or other natural fibers protective me?
MYTH 4: Spectacles and Sunglasses will protect me from the heat of an Arc Flash exposure
MYTH 5: I wear a face shield… that should be enough
MYTH 6: I wear a face shield… when would I need a hood?
MYTH 7: FR Clothing is all the same.
MYTH 8: ATPV = 100% Protection
MYTH 9: Aluminized clothing is an effective choice for protection from Arc Flash hazards.
MYTH 10: I am confused by the Table 3.3.9.3 in NFPA 70E. What exactly is a Hazard/Risk Category?

It is a good, practical real-word article that provides explanations demonstrating that all of the above are myths.

Every Industry Needs To Address Arc Flash Hazards

Steve Hudgik — Wed, 12 Dec 2007 14:51:00 +0000

Last Friday members of the International Association of Operative Millers' (IAOM) Wheat State District met in Wichita, KS. This is an international organization for grain millers. GrainNet reports that "Protecting millers against the dangers of an arc flash comprised the bulk of the technical session."

It is great to see industry paying attention to and addressing the need to implement arc flash safety. Although establishing safe work practices and labeling equipment that presents an arc flash hazard has been required by NFPA 70E for a number of years, many are still not aware of the hazards of arc flash.

To help increase arc flash awareness we have just published a new page on our web site that provides an overview and introduction to the dangers of arc flash. We will be publicizing this page in the materials we distribute to our customers.

To De-Energize or Not to De-Energize

Steve Hudgik — Mon, 03 Dec 2007 21:37:00 +0000

One of the most important decisions in planning an electric task is whether to de-energize. Whenever possible, live parts to which you might be exposed should be put into an electrically safe work condition, unless your employer can demonstrate that de-energizing creates more or worse hazards, or is not practical because of equipment design or operational limitations.

You might need to work live to avoid interrupting life-support systems, deactivating emergency alarm systems, or shutting down ventilation equipment for hazardous locations, for instance. And de-energizing would not be practical during testing of live electric circuits or work on circuits that are part of a continuous process that cannot be completely shut down.

De-Energizing
An Electrically Safe Work Condition

The most important principle of electric safety is, assume electric circuits are energized unless you make sure they are not. Test every circuit and conductor every time you work on them. The National Fire Protection Association lists six steps to ensure conditions for electrically safe work.

1. Identify all sources of power to the equipment.

2. Interrupt the load current, then open the disconnecting devices for each power source.

3. Where possible, visually verify that blades of disconnecting devices are fully open or that drawout-type circuit breakers are fully withdrawn.

4. Apply lockout/tagout devices in accordance with a formal, written policy.

5. Test each phase conductor or circuit part with an adequately rated voltage detector to verify that the equipment is de-energized. Check the voltage detector before and after each test to be sure it is working.

6. Properly ground all possible sources of induced voltage and stored electric energy (such as, capacitors) before touching. If conductors or circuit parts that are being de-energized could contact other exposed conductors or circuit parts, apply ground-connecting devices rated for the available fault current.

The process of de-energizing is "live" work and can result in an arc flash due to equipment failure. When de-energizing, follow the procedures described below in "Working On or Near Live Circuits."

The above was taken from a NIOSH article that also covers lockout/tagout and information about working on or near live circuits.

Removing the Confusion Over Electrical Standards

Steve Hudgik — Fri, 30 Nov 2007 15:53:00 +0000

"Not sure whether to follow OSHA or National Electrical Code requirements for electrical safety at your construction site? Here is guidance to help you understand the differences in four controversial areas."

That is the subtitle for an article in Occupational Hazards Magazine. The article then defines the problem:

"Electrical safety on construction sites continues to be a major issue. While progress has been made over the years, electrical accidents continue to rank high on the list of construction accidents. In some areas of the country, they are the second leading cause of death or serious injury."

"One reason that electrical accidents occur is because of confusion between National Fire Protection Association (NFPA) and OSHA requirements. Four areas in particular continue to spark controversy or are approached differently by different regulatory standards. There are ways to bring harmony to these four issues by providing recommendations to deal with the differences."

The four areas of confusion discussed in this article are:

Ground-fault circuit-interrupters and Portable Generators

Open Wiring on Insulators

Relocatable Power Taps

Arc Blast and Arc Flash Hazards

For the first three of the above there are updated codes that apply in these areas that are more restrictive than what OSHA requires. For example while OSHA does allow open wiring under some circumstance, NEC 527.4(B) and (C) does not allow it. The article recommends using the stricter code requirements, not because they are stricter but because they are safer.

Arc flash is on the list because arc flash hazards tend to be ignored during construction. The article states:

"In the last few years, considerable progress has been made in industrial facilities after the owners take occupancy. It is during the construction phase that there is little or no attention to this hazard. In many of our code classes for construction electricians, the majority states that this is the first time they have heard about this issue."

The article points out that arc flash is a danger during construction and the requirements of NFPA 70E must be followed during construction.