In 1983, the government made the move to build the first public shelters. 9 underground MRT stations of the North-South and East-West Lines were hardened as public shelters. Then in 1987, the government embarked on a comprehensive shelter programme beginning with public shelters at the foot of new Housing Development Board (HDB) residential blocks. Since then, public shelters have also been built in secondary schools, community centres and other public buildings.
In September 1994, it was announced that shelters (to be called Household Shelters) would be built inside new HDB flats so that their occupants would have quick access to protection in a war emergency. With this, the practice of building public shelters at the foot of HDB blocks was discontinued. The programme to incorporate public shelters in secondary schools, community centres and other public buildings however continued.
On 7 October 1997, the Civil Defence Shelter Bill requiring, among others, the compulsory provision of shelters in new residential developments was passed by Parliament. On 15 October 1997, the President assented to the Civil Defence Shelter Act 1997. A six-month grace period was given before the Act came into operation with effect from 1 May 1998.
Under the CD Shelter Act 1997, new dwelling units (both houses and flats) are required to have household / storey shelters incorporated in the developments.
With effect from 1 May 1998, applications for planning permissions for new flats or houses submitted to or lodged with Urban Redevelopment Authority (URA) are required to incorporate household or storey shelters.
If an application for outline permission, or an application for written permission (if no outline permission is made) for a residential development is made before 1 May 1998 and the permission was still valid as at 1 May 1998, the CD Shelter Act would not apply to that development. In addition, any subsequent submission for this same development will be deemed as re-submission and not new submission for the purpose of the CD Shelter Act as long as any permission granted by URA arising from this said application has not lapsed or become invalid.