Experiment Hazard Class 11 – Hydrogen


This hazard classification applies to all experiments and processes involving the use of gaseous hydrogen. This class includes work performed in the Experiment Hall Beamline Stations and any preparatory/setup/testing work performed in the LOM laboratories. Other hazard controls such as fire protection and life safety regulations may apply to experiments of this hazard class. A summary of controls for hydrogen use is available in the hydrogen summary document.

Experiment Category

Experiments involving previously reviewed hazard controls qualify for categorized as medium risk.

Experiments involving new equipment or modified hazard control schemes are categorized as high risk.

Experiment Hazard Control Verification Statements

Engineered Controls – Applicable controls for storage and use of hydrogen. The quantities of hydrogen used and/or stored must be limited. Flash back arrestors must be provided on all hydrogen supplies and must be located immediately downstream of the first regulator or other location determined by a safety review. Flammable mixtures of hydrogen are to be used in a ventilated, sprinklered area. Avoid the use of spark producing equipment.

Procedural Controls – SOP is required to define startup, shutdown, normal and emergency operations, purging, maximum flow rates for hydrogen, and PPE for handling gas cylinders. The need for an SOP is also required for small quantities of hydrogen. Line supervisors are responsible for the preparation and approval of the operating procedures

Design Reviews and Equipment Inspections – All experiments and operations involving the storage, use, or generation of hydrogen must undergo a documented safety review. The review may include not APS entities at Argonne. Any safety reviews provided by non-APS Argonne personnel shall be documented and forwarded to the APS User Safety Officer.

Training – Sector specific training for the facility using hydrogen.

Signs and Labeling – Contact AES ESH Coordinator for signs.

Personal Protective Equipment – Safety glasses, safety shoes when handling gas cylinders.Heat resistant gloves for temperature hazards associated with heat.

Dosimetry and Monitoring – Continuous hydrogen detectors.

Experiment Authorization

Unless otherwise noted in the approved experiment safety plan, the Director of the APS Engineering Support Division delegates the authority to authorize an experiment in this hazard class to a member of the APS Experiment Review Board and any of the persons in the beamline personnel that appear in the list of Beamline Manager personnel authorized to approve experiments.

Hazard Control Verification

The Director of the APS Engineering Support Division delegates responsibility for verifying that required controls are in place to personnel delegated the authority to perform this task to the experiment On-site Spokesperson, and Beamline Management personnel having experiment safety responsibilities.


ANL East ESH Manual Chapter 4.8, "Hydrogen Safety"

PFS-FEC consultation

NFPA 70 National Fire Protection Association

NEC National Electric Code.

OSHA Regulation 29CFR 1910.103

BOCA National Fire Prevention and Building Codes

Reviewed May 10, 2013