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 Post subject: NEW LABELING LANGUAGE
PostPosted: Tue May 05, 2015 7:46 am 
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Joined: Tue Jan 19, 2010 2:35 pm
Posts: 146
I'd like to hear other members views about the language I'm seeing on 2015 arc flash labels. I'm seeing "Shock Risk Assessment" instead of "Shock Hazard". What's your take? Do you think it's better, worse - more or less clear? I'm just interested to hear what you think it means? Thanks


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Tue May 05, 2015 9:16 am 
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Joined: Tue Oct 26, 2010 9:08 am
Posts: 2174
Location: North Carolina
A shock hazard assessment is very simple. If the current exceeds about 1-2 mA, there is perception. Above 100 mA, ventricular fibrillation becomes likely. If current is unlimited (for instance by using a high resistance grounding system), then another view point uses 50 V (or about 5 mA) as a cutoff. Above the lower threshold of around 1-5 mA, we have to consider for instance employees working at heights where they might be startled or otherwise jerk and create an additional hazard, irresptive of any physiological damage from the shock itself.

That pretty much concludes the shock hazard part of things unlike arc flash hazard assessments where it takes a much more detailed study to determine the magnitude of the hazard.

As for the risk assessment part of things, generally the view point is that there is a threshold distance beyond which a flashover will occur and if there is enough available current, a shock will occur. An inadvertent movement addition is also applied. Below a few kV, there are accepted standard values. Above that threshold, calculations are used. These values are given in a table format in 70E and that's what is generally printed on the labels.

Finally, the work methods have to be considered and whether or not appropriate PPE and/or tools are in use has to be considered. The design and specifications are also part of the shock risk assessment. This is where IEEE 516 does a pretty good job and 70E does very poorly in confusing the terminology and making recommendations that don't match the engineering standards. Essentially 70E based their shock risk assessment recommendations on IEEE 516 but made some "simplifications" that leave end users in some cases confused.


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Tue May 05, 2015 5:00 pm 
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Joined: Tue Jan 19, 2010 2:35 pm
Posts: 146
Hi Paul, Sorry, I wasn't clear. I was referring to the word RISK and the language on the 2015 labels.
The new labels say "Arc Flash and Shock Risk Assessment" followed with "Appropriate PPE Required". I wanted to hear from other users what they think that language means? By the way, thank you, you're a good resource and speaking for myself, I appreciate your knowledge.

Thanks for your reply,
Bill


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Mon May 11, 2015 7:59 am 
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Joined: Mon Jun 07, 2010 9:40 am
Posts: 119
I would say the use ofthe term "Risk Assesmaent" makes the intent less clear. Unless the intent is to make things less clear.


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Mon May 11, 2015 9:44 am 
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Joined: Fri Apr 15, 2011 7:43 am
Posts: 177
Location: Colorado
We are working through the term "Risk Assessment" as a consulting engineering company. We do not particularly care for "Risk" as we are in the profession of determining all of the risks associated. We are leaning back on arc flash hazard assessment to limit our liability.

Hope that is the direction your were looking for.


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Mon May 11, 2015 10:35 am 

Joined: Wed Jul 30, 2014 3:27 pm
Posts: 3
I'm stealing a quote from someone who's name I can't remember. "You can reduce risk but not a hazard". A hazard can be associated with any activity. Risk = Likelihood x Severity.


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Mon May 18, 2015 7:10 am 
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Joined: Tue Jan 19, 2010 2:35 pm
Posts: 146
Thanks to all of your who replied. Each comment helped and I agree with your observations. I took from your comments that the language does not clarify, but confuses.

engrick, your comment about working thru the language makes perfect sense and multiplies JKlessig comment on it being less clear.
I believe the overall purpose for arc flash and shock hazard labeling is to inform the user there's a hazard but more importantly, to quantify the hazard so the qualified person can take the necessary steps to protect themselves with PPE and also establish the proper boundary around their work area. The qualified person is told there's a hazard and given information on the amounts of each. Seems to me that's when a risk assessment should be done. You could easily find the same calorie level and voltage level on many labels, but on equipment as varied as soup to nuts.

Thank you all for your very valuable input and feedback.


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 Post subject: Re: NEW LABELING LANGUAGE
PostPosted: Mon May 18, 2015 7:11 am 

Joined: Mon Feb 22, 2010 10:24 am
Posts: 21
Arc Flash Risk Assessment is now required and is outlined in 130.5 of NFPA 70E-2015. Traditionally, we have done an arc flash hazard analysis which is basically the same as the new definition of an arc flash incident energy analysis. (Incident energy analysis term was introduced in 2012 edition The engineer would determine the incident energy and PPE would often be selected from the table (Table 130.7(C)(16) in the 2015 edition). The 2015 edition prohibits the use of this table for PPE selection when an incident energy analysis is performed (130.5(C)). It should only be used in conjunction with the tabular method of determining PPE categories. The 2015 edition requires tasks to identity the risk involved, not just the amount of incident energy. The employer or the consultant must conduct a risk assessment in addition to an incident energy analysis, not only for selection of PPE but for "appropriate safety-related" work practices, in order to meet the requirements. The topic gets much deeper than this, but that is the basic idea. You are allowed to use Informative Annex Table H.3(b) for PPE selection, but the intent is that a risk assessment be performed. If the consultant does not offer the risk assessment service, then it falls back to the employer to do it.Stay tuned for the 2018 changes.


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