A large, hydrogen-cooled generator is driven by steam turbines at a power station. During maintenance shutdowns, the hydrogen cooling loop in the generator is purged with carbon dioxide. After CO2 concentrations are measured with a densitometer to verify the complete removal of hydrogen, the generator is purged with air and the maintenance is performed.
A faulty modification to a multiple-gas piping manifold allowed mixing of hydrogen and oxygen that resulted in a storage tube explosion. Several employees suffered severe burn injuries from the incident.
While performing hydrogen gas release experimentation by thermally reacting a slurry of ammonia borane powder in silicone oil in a plug flow reactor, a discharge port on the test reactor became loose. A foaming white product was leaking from the fitting and discharging in the direction of the heat tape and insulation (back over the reactor). As a result, hot, reacting slurry flowed out of the port and was exposed to air. In the presence of oxygen, the slurry ignited, producing a green flame.