Mr Mao and Pyro Magic were fined HK$14,400 after pleading guilty to a number of charges relating to that incident, which involved fireworks left over from the Symphony of Lights rooftop fireworks display.

In 2001, a barge full of fireworks left over from the Tourism Board's City of Life - Hong Kong Is It! campaign launch, conducted by Pyro Magic, burst into flames at the Tsing Yi dangerous-goods anchorage area. Eight workers escaped injury. The Civil Engineering and Development Department said it also had a record of a serious, although non-fatal, incident involving the company in 2004.

Mr Mao yesterday denied the company had a problem with safety. Last week's fire was caused when fireworks debris landed on wooden mortar racks during the show, he said. Using wooden racks was the universal standard because material such as aluminium, which could fly long distances in the event of an explosion, was more dangerous.

'The wooden racks are mounted on the sand bed that is placed on the steel non-flammable barge surface,' he said. 'If fire does happen and continues, the wooden racks will simply be burned out on the sand bed. If the fire is small, our crew will put it out quickly, but if the fire is considerably bigger, we will let the standby fireboat put it out.'

Mr Mao said the company followed the regulations guiding fireworks displays set out by several government departments, regulations that became stricter every year.

'Before each fireworks display, Pyro Magic has to provide a method statement setting out the procedures and materials to be adopted in the fireworks display for the approval of the Civil Engineering and Development Department,' he said.

'We are certain and confident about the safety of the fireworks displays and the safety of the public.'

Mr Mao said the company's accident rate over the past 10 years was about 0.2 per cent. 'We have experience performing over 1,200 shows. Our continuous effort to strive for a perfect safety record is always our first priority.'

The department said fireworks operators needed to sit a written exam every year to maintain their licence. It also said their safety records were taken into account, but not how.

The Home Affairs Bureau vets applications for outdoor displays and advises other departments about its findings. It did not comment on Tuesday's incident. No fewer than 18 other departments are involved in the process leading up to outdoor fireworks displays.

Industry sources said accidents such as Tuesday's should not occur.

'This sort of thing is not common at all,' said a licensed pyrotechnician. He said that while the use of timber racks was common, it was relatively straightforward to fireproof them. 'If you do everything to specifications, you shouldn't have any problems.'