Controls for Hydrogen Systems

Purging

  • One should always assume that hydrogen is present and verify that the system has been purged to the appropriate level when performing maintenance on a hydrogen system.
  • Likewise, one should always assume that air is present and verify that the system has been purged to the appropriate level when reintroducing hydrogen into a system.

Pressure Relief System

  • Pressure equipment should be fitted with a pressure relief device (PRD), such as a rupture disc or a relief valve.
  • The PRD should be vented to a safe outside location.

Venting

  • Hydrogen storage facilities should be provided with adequate ventilation for both normal operating conditions and emergency situations.
  • Vent lines for hydrogen (including pressure relief lines and boil-off from cryogenic systems) should be vented to an appropriate exhaust system or a safe outside location.
  • The vent should be designed to prevent moisture or ice from accumulating in the line.
  • Unused hydrogen should be disposed of by venting or possibly flaring.