Warning Placards

All areas where hydrogen is stored or used should contain a permanent placard stating:

WARNING: HYDROGEN - FLAMMABLE GAS - NO SMOKING - NO OPEN FLAMES

Storage sites for liquefied hydrogen should also have a sign that reads:

WARNING: LIQUEFIED HYDROGEN - FLAMMABLE GAS - NO SMOKING - NO OPEN FLAMES

Signs should be placed on all liquid hydrogen vessels near the pressure-relief valve vent stack stating:

WARNING: DO NOT SPRAY WATER ON OR IN THE VENT OPENING.
photo: warning placard photo: warning placard