The death of a cadet firefighter during a training exercise was accidental, a coroner found yesterday. Allan Ng Lai-kwong, 34, died from heat stroke in a smoke-filled simulator at the Pat Heung Fire Services Training School in Yuen Long on July 10, 1997. Coroner Alison Thompson said Ng's death was likely to have been caused by a combination of factors. 'He might not have realised the gravity of danger he was in,' she said. The heat reached 60 degrees Celsius when his partner Wong Ka-hung escaped from the simulated ship fire. Both firemen's breathing apparatus was running out of air at that time. Ms Thompson said Ng broke the rule that the firemen must always work in pairs, possibly not wanting to leave without accomplishing his task. She suggested that had he had a more easily activated alarm it might have hastened the rescue attempt.