The 2014 edition of NFPA 51B now specifies that a hot work permit may be valid for a maximum of 24 hours. For a period exceeding 24 hours, there is a significant chance that personnel and conditions may change, and reevaluation is necessary to ensure a fire safe environment is maintained. The area should also be inspected once per shift by the permit authorizing individual (PAI), which will help to identify any changes in conditions that arose since the arrival of new personnel.
What information is needed on a hot work permit? Watch the video to find out.
These requirements can be found in section 5.4 of NFPA 51B (2014). There is a sample hot work permit in Annex A of the standard, which can be viewed for free here.
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