Update to NFPA 51B

by Jun 12, 2019Hot Work

NFPA 51B is full of useful information on the best practices for hot work. Along with the National Fire Code of Canada and CAN/CSA W117.2-M87 Safety in Welding, Cutting, and Allied Processes, it is essential reading to provide framework and safely perform hot works in conformity with the Safety Code for the construction industry (SCCI) and the Regulation respecting occupational health and safety (RROHS).

NFPA 51B aims to safeguard people and property from the fires and explosions that can arise from hot work. According to the NFPA, U.S. firefighters respond to 4,440 structural fires due to hot work each year. These fires and explosions cause deaths, injuries and hundreds of millions of dollars in damages each year. (Ahrens, 2016)

In 2019, NPFA 51B was updated to bring new ideas to its 2014 version, making it NFPA 51B-2019. It still contains everything one needs to know regarding hot work permits, who can authorize hot work and who can supervise it.

Furthermore, the changes in NFPA 51B-2019 add clarity to the standard:

  • The procedure for emitting hot work permits was reorganised to give more clarity to the process.
  • The process for reinspection of the work area after each shift was clarified in annex.
  • New definitions were added, namely for fire protection systems and fire watch
  • Additional explanations were added to help distinguish the practice of fire watching from fire monitoring as well as distinguish their individual requirements.

Additionally, some recommendations were modified to increase safety for property and workers:

  • Requirements for fire extinguishers were modified and harmonized with the requirements of NFPA 10, Standard for Portable Fire Extinguishers
  • Most notably change to NFPA 51B is the amount of time for which a fire watch must be held. It must now be held for a full hour (rather than the previous half hour after the end of works).

Lastly, the annexes were revised to reflect the changes in the body of the text.

  • The new version of the standard addresses the preparation of areas that were deemed inadmissible for hot work due to impaired fire protection systems.
  • The distinction between hot work by-product temperatures and combustible material ignition temperatures is compared in annex.

Happy reading!

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