Company bosses have been accused of failing to plan for a deadly explosion at the Pike River mine during an inquiry into the November disaster.
Mine safety and training manager Neville Rockhouse, who lost his son Ben Rockhouse in a series of explosions at the mine, is giving evidence to a Royal Commission of Inquiry into the disaster at Greymouth.
He came under heated questioning from Engineering, Printing and Manufacturing union counsel Nigel Hampton over safety concerns at Pike River.
Mr Hampton said company management had not taken steps to ensure a fresh air base in the mine would work after an explosion.
He asked Mr Rockhouse why he did not know the exact number of self-rescuers at the fresh air base.