The fire hazard posed by temples set up in homes came into the spotlight after a fire at one such home that claimed the lives of a father-and-son pair from Malaysia on Sunday.
According to the Taoist Federation, there are as many as 2,000 such temples that are open to followers.
Concentrated in areas such as Yishun, Kallang, Geylang and Mountbatten, most of these temples were meant to be temporary after their operators were evicted from kampungs from the late 1970s to the 1980s, the federation said.
The operators took their altars and idols to these homes, said the federation's administrator priest Chung Wei Yi, 29. But these items remained there over the years, as most operators could not afford to purchase land to build new temples, he said.
The fire on Sunday took place at a single-storey house in Jalan Gaharu - part of a private estate off Dunearn Road - that had a temple for devotees of the Taoist Goddess of Mercy Guan Yin. The two victims were tenants there.
Both the Taoist Federation and Singapore Buddhist Federation said they do not manage these temples. But both federations said they had previously encouraged some operators to adhere to fire safety regulations.
"They can house their gods there but, whenever they have celebrations, they will need to book a plot of land or a neighbourhood facility from the relevant authorities," said Priest Chung.
The Singapore Buddhist Federation said its 130 or so members are given fire safety guidelines, on matters such as the right fire safety equipment and drills. It does not keep track of unregistered temples. Chief executive Kua Soon Khe, 61, said some temple operators and their managements are "complacent", while others do not understand the guidelines, which are written in English.
Mr Ong H.H., 53, who took over his father's kampung temple - now housed in a flat in Serangoon North - said safety was his priority. "We keep the altar neat and tidy and have a fire extinguisher in the house," he said in Mandarin.
Astrologer Fabian Ng, 50, whose MacPherson Road terrace home also houses deities and altars, said the worship areas in his home are open only to his customers. He acknowledged that he has had complaints from residents, but said his altars are coated in fire retardant sprays, and tea-light candles are kept in covered glass holders.
Other religious groups also use residential premises as bases for their activities. These include Christian cell groups and home church services.
The Housing Board said the use of flats for public worship is "strictly prohibited" and infringes on the terms and conditions of the lease or tenancy agreement. As a last resort, the board can take action to "compulsorily acquire a home ownership flat, or terminate the tenancy of a rental flat".
The Urban Redevelopment Authority (URA) said private residential properties are not allowed to be converted into places of worship without prior permission. Its spokesman said the URA will investigate if it receives feedback on unauthorised activities.
The authority added that older places of worship located in private residences have existed prior to the establishment of the Planning Act in 1960. These are allowed to remain.
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