Personnel Requirements

Operating procedures should require that personnel:

• are familiar with the properties and characteristics of hydrogen
• have been trained by a qualified worker to operate the equipment
• are familiar with operating manuals of vendor-supplied equipment
• follow a formalized hydrogen training plan
• are trained to act properly in an emergency (See Incident Procedures)

The operating procedure defines whether at least two people (i.e., the ' buddy system' used by NASA) are needed to operate the system, and whether the system is authorized for overnight or unattended operation.

The operating procedures should identify who is authorized to operate and/or maintain the equipment and who can approve modifications of the equipment.

Operating procedures should define what personal protective equipment (PPE) must be worn when operating equipment or performing experiments with cryogenic or gaseous hydrogen.

All personnel working with LH2 or SLH2 who may be exposed to cryogenic vapors shall have eye and hand protection. Face shields are required when operating any hydrogen system under pressure and connecting or disconnecting lines or components. Systems should be designed and operated to reduce potential for unprotected personnel coming in contact with uninsulated piping or vessels containing cryogenic hydrogen.

Properly insulated gloves should be worn when handling anything that comes in contact with cryogenic liquids or vapors. Gloves should fit loosely and remove easily.

Adequate foot protection should be provided, and the trousers should be worn outside boots or work shoes. Open or porous shoes are not permitted.

Any clothing splashed, sprayed, or soaked with fuel vapors or oxidizers shall be removed until completely free of the gases.

Personnel should avoid wearing clothing made of nylon or other synthetics, silk, or wool because these materials produce charges of static electricity that can ignite flammable gas mixtures. Ordinary cotton, flame-retardent cotton, or Nomex clothing is preferred. Gauntlet gloves, tight clothing, or clothing that holds or traps liquid against the body must be avoided.

Hard hats should be worn as appropriate. Hearing protection shall be utilized as appropriate.

Personnel shall be provided appropriate protective clothing during cleaning or decontamination operations.

References

G-095-2004, ANSI/AIAA Guide to Safety of Hydrogen and Hydrogen Systems, can be purchased from www.aiaa.org.