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 Post subject: Continuous Process Operation
PostPosted: Tue Apr 19, 2011 1:07 pm 
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Joined: Tue Feb 17, 2009 11:04 am
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Could someone give me examples of a continuous process operation?


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PostPosted: Wed Apr 20, 2011 6:21 am 
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Location: New England
Refineries come to mind, as well as most all oil based commodities like ethylene, styrene, etc.


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PostPosted: Thu Apr 21, 2011 4:44 am 
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Location: Michigan
Continuous Process

Well the clarification in this [url="http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=25559"]OSHA letter of interpretation[/url] did not really match what I had considered infeasible and seems to fall more into the category of greater hazard insteadÔÇŽ

The NFPA-70E covers justification for live work in article 130.1 and gives three reasons; greater hazard, infeasibility and less than 50V. Under infeasibility it states, "energized work shall be permitted where the employer can demonstrate that the task to be performed is infeasible in a de-energized state due to equipment design or operational limitations."

The 70E handbook notes then go on to explain that, infeasible is defined in Merriam-Webster's dictionary as not capable of being done or carried out and that the dictionary suggests that the phrase "not possible" is a synonym for the word infeasible. For example, tasks such as diagnostics and measuring load current can only be done when the equipment is operating. However, it also says if it is not possible to de-energize by performing the work at a different time, then the task is infeasible to perform in an electrically safe work condition. Conversely, it cautions employers on using this too broadly and then references FPN No. 2 for examples.

FPN No.2 again says diagnostics and testing and then also includes work on circuits that form an integral part of a continuous process that would otherwise need to be completely shutdown in order to permit work on one circuit or piece of equipment.

An example of how we have interpreted this in the past has been adding a circuit to a 120/240V breaker panel, only since that particular breaker panel also fed the gas mixer which pipes shielding gas to all the MIG welders in the plant and the plant was running 24/7 plus through lunches and breaks with no end in sight. Another example where I work might be our paint line depending on the circumstances.


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