As part of preparing for material disposal, a small fire occurred within a fume hood as a researcher was combining several spent ammonia borane (AB) samples that had previously been stored uncovered in the back of the hood for 6+ months. These AB samples consisted primarily of two 40-gram products of a 50wt% AB in silicone oil that had been thermally dehydrogenated. A small amount of unreacted AB slurry is believed to also have been present.

During project clean-up, partially spent (thermally reacted) ammonia borane (AB) residue from a previous experiment was mixed with a small amount of water to rinse the residue from its container. The water reacted with the spent AB resulting initially in a large heat release followed immediately by a fire. It appears that the water addition view more

Within the International Space Station (ISS) oxygen generator, an increase in differential pressure across a pump supplying return water to a PEM electrolyzer fuel cell stack had persisted over a 4-month period and was approaching the shut-off limit for the system. This decrease in performance was suspected to be caused by water-borne catalyst fines containing platinum black and Teflon®* binder materials, shed by the fuel cell stack, and accumulated within the pump's inlet filter. Maintenance in the field was required.

The system had been designed for factory maintenance, and no contingency had been planned to handle field maintenance for such a circumstance. An initial assessment of hazards for the proposed filter maintenance raised the concern that opening the water line view more

A five-pound CO2 cylinder being stored in a compressed gas storage cage at a power plant failed catastrophically and became a missile. The cylinder destroyed the storage cage, then struck one of six stationary hydrogen storage cylinders used as emergency make-up for the hydrogen supply system. One of the hydrogen cylinders was broken away from its mounts and moved 10 feet from its original location. The loss of this cylinder severed the manifold tubing, creating a leak path to the atmosphere for the remaining five hydrogen cylinders. The leaking hydrogen gas apparently self-ignited, engulfing the immediate area. The site fire brigade responded and used hose lines from a distance to provide cooling until the hydrogen supply was consumed. The fire was out within seven minutes, and no off view more

The over-pressurization of a laboratory ball mill reactor designed for operation under slightly elevated pressures resulted in a serious injury. The apparatus had been routinely operated under argon and hydrogen pressures of 5-10 atmospheres for nearly two years. The apparatus had not been tested for operation at pressures greater than 10 atm.

A visiting intern, frustrated in attempts to hydrogenate magnesium silicide through ball milling in the previously noted pressure range, attempted to perform the operation at higher pressures. The approximately 70-ml reactor was loaded in a glove box with 0.5 g of magnesium silicide and six milling balls. Upon pressurization to 80 atmospheres, a 270-degree rupture occurred around the perimeter of the reactor. The blow-out of the reactor view more

A water treatment plant used an electrolytic process to generate sodium hypochlorite (NaOCl) from sodium chloride (NaCl). The strategy of using liquid sodium hypochlorite for disinfecting water instead of gaseous chlorine (CL2) is popular because the liquid is generally safer and falls under fewer OSHA and EPA standards. The further idea of generating the liquid sodium hypochlorite on an as-needed basis and in limited quantities also has certain obvious safety advantages.

One of the disadvantages of the electrolytic process is that hydrogen gas is also created as a byproduct. The hydrogen is supposed to be vented, by design, to the atmosphere before the liquid sodium hypochlorite passes into a holding tank.

For various reasons, in this instance it is believed that the view more

Hydrogen was stored in a plant in a 42 ½ ft diameter sphere made of 3/16 inch steel. The sphere was partitioned into two hemispheres by a neoprene diaphragm attached around the equator. Hydrogen was stored under the diaphragm, while the upper hemisphere contained air. An explosion-proof fan was situated in the upper portion of the sphere in order to provide a slight positive pressure on the top of the diaphragm.

When the plant was shut down for a local holiday, the fan on top of the hydrogen sphere was also stopped. During plant startup two days later, a violent explosion occurred in the sphere. The sphere shell was torn into many sections by the explosion, and some of the sections were propelled as far as 1,200 ft. Some of these sections struck flammable liquid storage tanks view more

A 30-milliliter (mL) vacuum bulb, equipped with a glass stopcock, containing one gram of pentacarbonyl manganese hydride exploded in a refrigerator. This caused the breakage of three other containers, releasing some contents into the refrigerator. The chemicals did not react. The refrigerator contained numerous reactive and flammable chemicals, mostly in glass containers.

The damaged containers were removed and relocated under a hood. The refrigerator was then examined for other breakage and inventoried. All breakage was cleaned up. The safety coordinator was notified and began an investigation.

The direct cause of the occurrence was the failure of a glass vacuum bulb, which either fractured due to some unforeseen chemical reaction forming hydrogen gas, or was unable to view more

The interior of a small high-temperature furnace, approximately 24 inches high by 18 inches wide, became contaminated with an unknown material later identified as magnesium. The furnace was disassembled to clean the unknown material from the interior surfaces, and while attempting to clean the bottom of the furnace, the technician tapped the upper lip of the furnace with a spatula and the magnesium flashed. The technician was stepping back from the furnace when the magnesium flashed. He received minor eye irritation and his eyebrows were singed.

Later that week the same technician was attempting to clean the interior surfaces of the top of the furnace and sprayed, as directed, the interior of the top with a water-based cleaning liquid which consisted of 91% water. He stepped view more

An unplanned shutdown of the hydrogen supply system occurred, affecting the hydrogen furnaces in the plant. The apparent cause was an inadvertent valve closing, which was contrary to the written procedure.

A preventative maintenance activity was being conducted on the hydrogen gas system. Shortly after starting that work, various hydrogen gas users notified the emergency response personnel that the hydrogen supply safety alarms sounded, indicating an interruption of the hydrogen gas supply. As a result, the hydrogen furnaces shut down. This shut down is an automated process which injects an inert gas (nitrogen or argon) to prevent the introduction of oxygen and its mixing with any hydrogen gas. All shut downs functioned as designed. As a precautionary measure, fire protection view more

While research staff were working in a lab, a staff member opened the primary valve to a 0.2" (1500 psi) hydrogen gas line connected to a manifold supplying instruments in the lab. Upon opening the valve, the hydrogen gas line failed at a fitting on the switching manifold, releasing a small amount of hydrogen gas. The staff member closed the valve immediately, then inspected the gas line and found the front ferrule (of the compression-style fitting) to be missing. There were no injuries or damage to equipment.

In the follow-on discussion with research staff, it was learned that approximately one month earlier, a similar condition (front ferrule missing from a fitting) was found while performing a modification to a similar manifold. Following a critique, management expressed view more