The wealthy owners of a warehouse business feared to be the scene of the deadliest blaze for firefighters for 30 years are expected to be questioned about possible breaches of safety laws.

Wealmoor Atherstone, a vegetable packing company, is owned by Ratilal Dhanani, 77, whose family fortune is estimated at £5.2 million.

Rescue experts resumed their search yesterday for three firefighters missing since Friday in the ruins of the warehouse where a colleague was killed when the roof collapsed.

Police said that the inferno was being treated as suspicious, although it was too soon to say if arsonists were to blame. Experts said the intense heat was surprising if the building contained only typical food factory pallets and wrapping plastics.

Specialist rescue crews, trained for disasters such as earthquake relief, arrived yesterday at the industrial estate in rural Warwickshire with little idea of what they would find. The 100-strong team will use diggers, listening equipment and cameras to search for survivors. They will also make records of what may become a major crime scene.

The authorities faced a troubling lack of information about the warehouse. Forty-eight hours after the blaze was reported the fire brigade could not say whether there had been any workers inside the building when the fire broke out.

The company that owns the warehouse said last night that its evacuation procedures had been properly followed and it was not aware of any missing workers. “I’m aware that all our fire evacuation procedures were followed at the time and they were followed calmly and correctly,” said Avish Malde, a director of the company.

“At that time of day it would have been an end of shift so there would have been a few people there.”

Fire officers were also unable to confirm whether the building, where the 300 staff included many migrants, had a sprinkler system. However, a fire protection specialist disclosed that he had started installing anti-fire “misting” equipment for the building’s previous owners, but the job was never finished.

The food company is likely to face tough questions. Mr Dhanani’s main Wealstone business, run with his wife, Vilasgauri, has been operating since 1973 and distributes 60 types of exotic fruit and vegetables from 55 countries.

Under the newly adopted Fire Safety Order 2005, operators of premises face unlimited fines and potential prison sentences unless they follow strict rules to safeguard all “relevant persons”. Some commentators believe that this new duty extends beyond the safety of workers, visitors and neighbours to include protecting firefighters called to tackle a blaze.

Businesses must by law have trained staff on site during working hours to evacuate buildings so that the fire brigade can be informed on arrival whether anybody is trapped. One report quoted local people claiming that migrant workers on long shifts had been known to sleep at the warehouse. If so, the building would be deemed to be a hostel and the owners would have been required to include alarms and special lighting to help them to escape from fires. Companies, as well as individual bosses, may be prosecuted under the new law, which is enforced by local fire authorities. The reform has shifted the burden of proof onto employers to show that they took all necessary precautions.

The Dhananis are 177th on the Asian rich list. Wealmoor imports chillies, okra, ginger, sweet potatoes, papaya, lychees, figs, dates and kumquats, mainly from West Africa. Some of their produce is organic.

Health and safety officials are expected to start investigating why four men entered the warehouse just before the structure collapsed.

The firefighters entered the burning building, which has foodpacking, storage and office areas, on Friday evening. The roof collapsed on them at 7pm. One man, Ian Reid, was pulled out but died in hospital.

Fire protection experts yesterday accused ministers of ignoring demands to make sprinkler systems compulsory in large warehouses. After a series of major fires a decade ago, the Government required retail warehouses such as B&Q and carpet sellers to install sprinklers if their premises were 2,000 sq m (21,500 sq ft) in size. A typical Tesco supermarket is 12,000 sq m.

However, building regulations, which were most recently updated last year, still permit identical tin box-style buildings to be used as factories, stores or gyms without sprinklers, up to 20,000 sq m in size.

Britain stands alone among advanced European countries on this issue, says the British Automatic Fire Sprinkler Association. “We are very keen that Government doesn’t get off the hook,” Stewart Kidd, the association’s secretary general, said. “For some reason Westminster has decided that they will listen to the lobbying from the warehouse side rather than the fire brigades, fire protection associations and fire trade organisations.”

The devastated warehouse, a former aircraft hangar on fields near Atherstone on Stour, close to Stratford-upon-Avon, is estimated to be 1,300 sq m. A full sprinkler system for such a building would cost about £170,000 but would pay for itself in a decade because of reduced insurance costs.

The previous owner, Bomfords, began installing automatic fire protection equipment but went into administration. The new owner, whose headquarters are near Heathrow, took over in July. Sidney Dawson, of Prestige Protection Systems, said that he had started fitting the gear. “The actual water misting system was about 75 per cent completed. It covered the main storage area,” he said. “There were all sorts of packing materials stored there. To the best of my knowledge there were plastic boxes, there was cardboard. You can’t partially deploy a water misting system, it can only be implemented by the main discharge pump which pressurises the system. We hadn’t fitted it yet; it was still down at the warehouse.”

The blaze is feared to be the worst loss of life by firefighters since seven died at a warehouse in Glasgow in 1972.

Wealmoor Atherstone said that members of staff had been questioned by police. “We are totally devastated, our thoughts and prayers are with the families of the firefighter who has lost his life on Friday night and the three others who are missing,” Mr Malde said. “Our priority is now is co-operating fully with the fire service and the police to establish the cause of the blaze. I’m aware that all our fire evacuation procedures were followed at the time and they were followed calmly and correctly. I’m not aware of anyone staying overnight.

“We took over the site in August and during that period we haven’t installed a fire sprinkling system. There were plans to do so.”

What every employer must do

— Establish appropriate procedures, including regular safety drills, to be followed in the event of serious and imminent danger

— Ensure that all employees are provided with adequate training

— Provide emergency routes and exits leading as directly as possible to a place of safety

— Nominate a sufficient number of competent persons to evacuate the premises

— Equip the whole premises with appropriate firefighting equipment, fire detectors and alarms

— Ensure that it is easily accessible, simple to use and indicated by signs

— Arrange necessary contacts with emergency services for firefighting, rescue work, first-aid and emergency medical care

— Ensure that information is made available to all the relevant accident and emergency services to enable them to prepare their own response

Source: The Regulatory Reform (Fire Safety) Order 2005

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