Section 421 - HYDROGEN CUTOFF ROOMSBrowse as ListSearch WithinSubsection 421.1 - GeneralSubsection 421.2 - DefinitionsSubsection 421.3 - LocationSubsection 421.4 - Design and constructionSubsection 421.5 - VentilationSubsection 421.6 - Gas detection systemSubsection 421.7 - Explosion controlSubsection 421.8 - Standby power