Fire at a generator of a power plant

A hydrogen leak occurred on the a coolant pipe of an electrical generator located in the turbine building, at 200 m from the reactor. Because of the welding works ongoing at that moment on the pipe, the hydrogen ignited and an explosion and a fire followed the leak, with one fatality and a severe injury. The fire brigade of the plant were able to extinguish the fire.
There has not been any radioactive release, because the accident occurred in the non-nuclear area of the plant.
According to the source (ARIA) the investigation attributed to a human error the cause of the incident.

Soldering work was ongoing on the pipe when the incident occurred. Authorities pointed out a human error. However, with the scarce information available, the cause could be equally well be attributed to wrong (maintenance, purge) procedures.

cooling system, turbine-compressor unit, turbine bulding

The nuclear reactor was stopped and under maintenance. Soldering work was ongoing on the affected pipe.

There has not been any radioactive release, because the accident occurred in the non-nuclear area of the plant.

Plant staff extinguished the fire rapidly

The ARIA report does not mention any lesson learnt, only the probable classification of the accident to a human error. The event description does not provide enough details to draw specific conclusion. Nevertheless, soldering/welding a hydrogen-containing component requires always the preliminary evacuation of the hydrogen, what does not seems that has happened in this case.
In alternative to a human error, this event could also hint at lack of adequate procedures, their or inadequate communication.