The boiler that exploded at a clothing factory last week killing one woman and injuring seven, including a pregnant employee, had an expired safety permit, the government said yesterday.

Phork Sovanrith, secretary of state at the Ministry of Industry and Handicrafts, said that Zhen Tai – a supplier to Levi Strauss & Co and Dutch chain C&A – was operating the boiler under a permit that had expired in early February.

“[Zhen Tai] didn’t come to us to extend the permit … [and so] no experts checked it, and as a result there is an explosion; this is the mistake of the factory,” he said, adding that the ministry has a team investigating the incident. “Legally [Zhen Tai] will face charges, because people died,” he said.

The factory’s boiler operator was detained a day after Wednesday’s blast.

Zhen Tai representatives hung up on reporters’ calls yesterday.

Moen Tola, of labour rights group Central, said it wasn’t clear where the responsibility lay. “First we need to figure out whose mistake it is, either the management, either the boiler operator, or the authorities, but . . . the operator should not be solely accountable,” he said.

Many questions remain, he added: whether the operator kept daily inspection logs, was ministry-certified and notified his superiors of irregularities in the boiler, and whether management responded.

Secretary of State Sovanrith said that over the past month the ministry had sent out notices to over 1,000 factories regarding boiler permits, but according to Tola only a ministry expert can determine whether a boiler is safe to operate to start with, a determination made only once a permit is applied for.

What’s more, according to both Tola and the Solidarity Center’s William Conklin, it is unclear whether the detained operator has had any legal counsel. “The police would not let our lawyers meet the worker to get a thumb print on the legal representation form,” Conklin wrote in an email yesterday.

Ty Sophon, the husband of the worker who died – Kor Samon, 48 – said he is still waiting for compensation from the National Social Security Fund. “The company needs to face the law, because I lost my wife, and [the NSSF] also needs to compensate me,” he said.

On the other hand, Yen Byn Ly, 26, the husband of Khy Srey Moa, 23 – whose injuries may cause her four-month pregnancy to miscarry – said that Zhen Tai had provided the couple with $1,000 in compensation for emotional damages and offered to transfer Srey Moa to Thailand or Vietnam for treatment.