Rats in bedrooms, dirty cooking areas, toilets which do not flush - a small number of purpose-built living facilities for foreign workers here are more dump than dorm.

Large purpose-built dorms - described as the best way to meet the accommodation needs of the 380,000 or so work permit holders living here - have sprung up on Singapore's outskirts in recent years. Most premises are well-maintained with air-conditioned sick bays, gyms and games rooms.

But workers staying in three purpose-built dormitories in the northern and north-western parts of the island say they have plenty to complain about.

At Ama Keng Hostel in Lim Chu Kang, several residents told The Sunday Times that there were mice in the bedrooms. These mice have attracted snakes as well. And for every 10 toilets, there are around seven that cannot be flushed properly. "I don't know how many dorms there are in Singapore but I think this is the (worst) one," said a Bangladeshi marine worker, 35, who gave his name as Mr Roki.

A spokesman for the dorm operator said if the conditions were so bad, tenants would have reported them. "We have our cleaning service that cleans every day. It's stayable," he added.

At Kranji Lodge 1 in Kranji Road, workers from China complained that rooms, which host about 10 workers each, are stuffy and they are not allowed to plug in extra fans. They are also often woken up by rats and cockroaches.

A construction worker, who wanted to be known only as Mr Zhou, said a rat once landed on him, causing him to hit his head on the base of the upper bunk bed. "I didn't realise Singapore could be so dirty," said the 27-year-old who had been staying there for three years.

The dorm's operator did not reply to queries by press time.

At Simpang Lodge 2 in Yishun, residents return to dirty toilets and kitchens and rats, plus there are no washing machines, said an Indian painter who gave his name as Rone, 36.

The dorm has a bed capacity of 9,000, but workers said it only has space for a few hundred to sit and eat during mealtimes. They also said there are not enough washing machines but if they wash their clothes in the toilets, they can be fined $30. Dorm security manager Anthony De Silva said washing of work clothing in the washrooms is not allowed to prevent debris from soiled clothing from clogging the plumbing.

Weekly anti-rodent measures are also taken by the pest control vendor, and additional traps are put out if workers complain, he said. "But if a single resident does not clean up, for instance his cooking utensils, that is enough to trigger rodent nuisance," he added.

Mr Rone said the rooms were clean and new when he moved in around four years ago, but conditions deteriorated after a year as the dorm became more crowded.

The Ministry of Manpower and other government agencies conduct regular inspections of dorms, said an MOM spokesman. If dorm operators do not provide adequate living conditions for the workers, they may be issued a warning, fined or face prosecution, depending on the severity of the breach.

MOM, one of several authorities regulating foreign worker housing, said there were complaints about living conditions in two purpose-built dorms last year. "One operator has received a warning letter, while the other is being investigated. Both have taken action to address the complaints," said the spokesman.

The ministry is now looking into two other purpose-built dorms that may have flouted the rules.

There are around 50 purpose- built dorms in all.

Transient Workers Count Too executive committee member Debbie Fordyce said that even if living conditions are hard, most workers will not speak up about it.

She added: "They would rather endure an awful lot of hardship than make a complaint that could cost them their jobs."