1. Train personnel on delivery procedures and emphasize the safety aspects of hydrogen connections and disconnections, and verification of clearance for trailer movement prior to departure.
2. Provide site-specific delivery procedures…

An investigation team was formed to determine the cause of this anomaly. The team performed a fault tree analysis which identified the following five main paths or gates: fault in the original weld, age, component not built per design intent,…

The incident resulted from an inadequate design for the storage location of the copper gas supply tubing (too close to an electrical outlet). The gas supply tubing was too long for its intended purpose and posed a hazard in its coiled state near…

1. Increase physical protection, shielding, and securing of transported hydrogen tube valves, piping, and fittings from multi-directional forces that are likely to occur during accidents, including rollovers. Reference: 49 Code of Federal…

1. A hydrogen tube pressure indication system needs to be developed that is robust enough to withstand an accident, indicates hydrogen pressure regardless of valve position, and would be visible from a safe distance during an accident situation…

This incident illustrates how difficult it is to completely purge hydrogen out of a large, complex piece of equipment. Uniform mixing and dilution is unlikely in all the partially enclosed spaces, crevices, etc. If a hazardous operation such as…

Personnel should be properly supervised, and supervisors should be aware of the activities of their personnel. Personnel must be motivated to adhere to established policies and procedures. All personnel associated with potentially hazardous work…

• All tank trailers should have a safely accessible auxiliary shut off valve in case of spills.
• Emergency personnel need to have access to all of the appropriate protective clothing, including shoes. Liquid hydrogen is stored at 20…

The use of inerting gas or other means of separation should be employed when conducting mechanical work where hydrogen gas could be present. More importantly, per CGA S1.3, the vessel should be equipped with a dual relief system that can isolate…

All valves and connectors should be clearly labeled to minimize chances for mis-connection. All technicians must be trained on proper procedures for both taking systems offline and bringing them back online.

Valves for compressed hydrogen…

First, it appears that the system may not have been vented properly. CGA G-5.5 should be used for determining safe locations based on the variables of the specific setup. Also, if the compressor was tied to a storage system, a backflow prevention…

Because of the near invisibility of a hydrogen flame in daylight and hydrogen's extremely low ignition coefficient, if a known leak is present (e.g., an audible hissing), ignition should always be presumed. The primary cause of this incident…

The tube was 403 stainless steel, which is subject to hydrogen embrittlement. It is requested that all gauges that have bourdon tubes be replaced with 303 stainless steel.

A web-based resource developed by Sandia National Laboratories to…

The charging characteristics of a battery vary with the condition of the battery and are proportional to the ampere-hour capacity of the battery. During charging, when a battery is close to being fully charged, hydrogen and oxygen both offgas in…

It is characteristic of silver/zinc batteries to outgas both hydrogen and oxygen for several hours after discharge. Also, in the future, the battery should be properly secured inside the container.

Refueling operations need to be conducted in a careful and attentive manner, and operators need to be aware of the potential consequences of their actions.

Extra caution should be taken when working around elevated pressure storage tanks. Pressure relief valve settings should be checked and then verified by a second party if possible. Proper procedures need to be followed at all times.

Normally hydrogen fires are not extinguished until the supply of hydrogen has been shut off due to the danger of re-ignition and explosion. During a gas leak/fire, it is important to shut off the source of the hydrogen if it is safe to do so. If…

Lessons Learned The site initiated the establishment of a field patrol and strengthened their onsite monitoring of mechanical equipment during a plant-wide temperature rise.

• Quantitative control of tightening torque on bolts…

Hazard analysis should consider potential leak locations, potential ignition sources in the vicinity, and the potential for accumulating flammable gases in that area.

Users should leak-check all cylinders upon installation. This event…