Some hydride materials (e.g., sodium alanates) may be rapidly exothermic, even pyrophoric, if exposed to water or humid air or slowly exothermic, even pyrophoric, if exposed to oxygen. Reactive materials, including fine metal powders, should be…

The manager in charge acknowledged that, while he made relatively recent modifications to the high-pressure gas storage side of the system and had directed a major rebuilding of various units, the moderate-pressure interconnecting system (the…

This incident occurred due to moisture in the sample line monitoring system. Removing moisture from the sample line increases the reliability of the equipment. Further evaluations are being considered for improving system reliability.

Although most of the hydrogen fluoride piping system was open to the atmosphere before the elbow was cut, the lines were not purged. Two plugs of residual material on either side of the elbow remained in place, thus allowing hydrogen to be…

Follow-up investigation of this occurrence confirms that it was inadvertent. Attention to detail while performing any task is a must for all personnel. This is to insure the safety of both the individual performing the task and others that may…

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.

The site needs to implement a good Operational and Readiness Inspection procedure. System inspection deficiencies need to be identified, and (if possible) reviewed by a second party before future tests are conducted. This inspection could include…

Proper bolt identification can prevent similar occurrences in the future. This can be achieved by simply painting the critical bolt heads a certain color (or by purchasing bolts with painted bolt heads). An explanation form should then be clearly…

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.

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…

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 combination of the cold water temperature (reducing the fatigue strength of the bolt), and the abnormally high number of cyclical stresses imposed by the imbalance from the hydraulic system check valve failure resulted in the failure of the…

Proper installation of check valves and other equipment should be visually inspected prior to pressurization.

Maintenance on the low-pressure venting system was not occurring at regular intervals. Ventilation integrity is now checked before starting an experiment.

Excessive venting of hydrogen from the tank due to lower facility consumption, in combination with extreme temperature conditions, placed thermal stress on the gland nut, causing a leak. The low consumption of hydrogen resulted from the shutdown…