12. The construction, maintenance or alteration of a distribution system for medical non-inflammable gas or an air intake system for medical use in an institution must be carried out in accordance with Standard BNQ-5710-500 (83 09 09), and the Protocole de certification des réseaux de distribution dans les établissements de santé - Gaz médicaux ininflammables BNQ-5710-900 (83 09 09).