The fatal toppling of several stacks of shipping containers at Kwai Chung and Tsing Yi had observers demanding answers yesterday and the terminal operators crying out for more space. The powerful winds that struck on Monday, sending containers hurtling down on unsuspecting workers and killing a truck driver, are normally preceded by several typhoon warnings, which escalate as the storm gathers power. The warnings give workers time to level the stacks and lash thousands of boxes together before heading for shelter. But Monday's gale came out of nowhere. Hutchison's Hongkong International Terminals (HIT), lessors and managers of the property where the fatal accident took place, are refusing to comment on operational procedures during investigations. But what is immediately clear is that the practices at the yard are no different from those employed at most other terminals and ports in the city and across the region, according to senior port executives. Whether those practices adequately protect workers on Hong Kong's space-constrained docks remains open to question, they say. The Kwai Chung docks are the busiest in the world, moving 13.4 million containers last year. Handling that many units requires storage space for about 280,000 boxes and, with limited space for storage, they must be stacked. The containers that fell on Monday, crushing 47-year-old driver Chan Shui-sang, were empty and stacked at least seven high. Regulations don't govern how high boxes may be stacked, but seven high is common at ports from Shenzhen to Singapore. The Kwai Chung facilities are industrial premises and regulated by the Labour Department. The department sets down guidelines for operators, which are not law and therefore not mandatory. Failure to follow each one of the guidelines is not in itself an offence, but failure to offer 'a safe working environment' is penalised, according to the department. 'Under the general duties provisions of the factories and industrial undertakings ordinance, a duty-holder who failed to provide and maintain a safe system of work in connection with container operations in adverse weather conditions is liable to a fine of $500,000 and to imprisonment for six months,' a department spokesman said. Industry veterans said the ordinance's vague guidelines made it hard to know when safety rules had been violated. But one terminal executive offered a solution. 'The government should allow us to have additional yard space,' he said.