Subject Personal H2S monitor placement
Background Based on industrial hygiene practices, personal H2S monitors shall be in or near the breathing zone as indicated by the photo below. The back of the hard hat is not acceptable.


What is considered breathing zone:

A hemisphere forward of the shoulders with a radius of 6-10 inches.

  • On hard hat – ears forward
  • On lapel
  • On front shirt pockets
  • Between shirt pockets and lapel