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…

Lessons Learned
Construction errors are difficult to detect once construction is complete. It is important to develop and use a systematic oversight process for minimizing construction errors during the construction process.

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Although a functional fire protection system would have helped to extinguish the fire, a properly installed hydrogen detection system, coupled with a properly designed ventilation system, could have prevented the incident altogether.

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Routine maintenance activities on pressurized hydrogen systems should be conducted per written design specifications. The procedures should provide detailed oversight regarding bolt, nut and fitting replacements or repairs. A formal review…

This incident emphasizes the need for proper gas detection and ventilation systems, as well as fire suppression systems, in laboratories using and storing hydrogen. This is especially true when open flame burners are in close proximity.…

Hazards should be eliminated to the extent possible rather than depending on workers to follow an operations manual.

Potassium carbonate draw-off operations should be improved, and the operations manual should be revised. The manual…

Fail-safe position of control valves in supply lines must be set correctly to prevent damage to pressure vessels.

Recommendation

Set all valves for fail safe operation (open or closed) according to needs before installation…

1. The dilution water for making a polythionic acid aqueous solution was changed from industrial water to pure water to lower the chlorine concentration in the piping.
2. Water that accumulated in the drain was removed before heating…

1. The plant tried to increase production and decrease workload, but failed to notice the potential negative outcomes of this change.
2. It is necessary to thoroughly simulate all potential negative outcomes of a change in procedures…

• Operation and management of the hydrodesulfurization unit should be strengthened to account for abnormal phenomena such as local corrosion.
• The safety review system for remodeling existing equipment and facilities should be…

• Verify that all PRDs contain fuse-backed adapters.
• Explore elimination of rupture disk PRDs and substitution of spring-style relief valves.
• Develop new hydrogen unloading procedure using a written checklist. * Add…

• A redundant safety circuit was put into service and the tank returned to normal operation after the failure. Both rupture discs were replaced and the tank was inspected.
• Important to note that the safety system functioned as…

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…

In the future, this mesoporous carbon material and ammonia borane:mesoporous carbon material will be handled under anaerobic conditions (glove box) to prevent further incidents.

No Lessons Learned, Specific Suggestions for Avoidance, or Mitigation Steps Taken.

• Unprotected hoses are susceptible to glass shards, abrasion, and burns during normal use. This leak was formed from a glass shard penetrating the tube wall.
• Flexible hoses require protective sheaves to avoid cuts, abrasions and…

This occurrence underscores the importance of appropriate design, equipment selection, and design review; the potential drawbacks of sharing utilities with other facilities; and the need to simplify [in this case, glove box atmosphere…

1. There should have been greater awareness during the design and installation of the burn box regarding the static pressure limitations of the exhaust fan in relation to the anticipated static pressure buildup across the HEPA filter.
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This occurrence underscores the importance of completing a hazard analysis for each different process. Non-safety-related systems or equipment may be used for purposes other than their primary purpose so long as potential hazards are identified…

The risk of a serious fire occurring inside the chemistry laboratory hood from use of hydrogen gas and/or presence of a small quantity of hydrazine-hydrate was underestimated. Additional control measures were required to reduce the risk of fire…