CD Shelters

General Information

1. What is the History of the CD Shelter Programme?
   

   Before the 1991 Gulf War, the sheltering concept was based on the public having sufficient warning time to seek refuge in public shelters. Such facilities were then being built at the foot of new HDB residential blocks, schools, community clubs and other public buildings.

   Learning from the Gulf War, it was noted that the warning time of an impending attack in any future conflicts could be as little as a few minutes. Hence, following a review of the shelter programme in 1993, it was decided to bring shelters closer to the people.

   The concept of having shelters within dwelling units (or in a common area at each storey of the building) meets the basic sheltering requirement
   - having occupants in shelters within the shortest time possible after the
   sounding of the Public Warning System.

   By comparison, a communal shelter at the building basement would take
   occupants a much longer time to reach from their dwelling units. This would considerably increase their exposure to weapon effects before they reach the safety of the communal shelter.

   Other factors favouring household shelters over communal shelters include the following:
   
   - Little maintenance required of household shelter in normalcy as it is a peacetime functional space (as store room or pantry) in the dwelling unit.
   
   - Not necessary to set aside space for building communal shelters at the void decks. Hence the space can be released for other social and recreational uses.

   [Public shelters (underground MRT stations, schools and community centres/ clubs) would be more suitable for people already in the open and those on the move.]

   In Sep 94, the Government made the announcement to build household shelters inside new HDB flats (encompassing those tendered for construction from Apr 95 onwards), and the practice of building public shelters at the foot of HDB residential blocks was discontinued.

   The enactment of the CD Shelter Act 1997 on 7 Oct 97 made it compulsory for all new houses and flats to be built with shelters (owners/developers have the option to build either household or storey shelters in their developments). A grace period of 6 months was given before the Act came into effect on 1 May 98. This allowed building industry practitioners to adapt to the new policy.

2. Are household shelters and storey shelters as safe as basement shelters and void deck shelters?
   

   The safety provided by household and storey shelters is comparable to that provided by shelters at the foot or basement of the block. Such protection comes from a combination of the strengthened walls, ceiling and floors; and the setback distances of the shelter walls from the building's exterior.

   Singapore's apartment blocks are robust structures that will not easily collapse even after being hit by a bomb (although localised damage to the block is expected). Because household shelters are stacked one on top of another, they form a continuous vertical hardened tower with a firmfoundation to provide added stability and resilience against collapse.

3. Can requirements for household shelters - which restrict the design of flats - be relaxed?

   The specifications for household shelter space, wall thickness and protective doors are governed by technical requirements issued by SCDF and BCA. These specifications are reviewed from time to time, with inputs from professional bodies such as the HDB, SIA, IES, ACES. The discussions also take into consideration the current and future building trends, and recommendations are implemented where possible.

   For example, the minimum shelter size and setback distances were also reduced in Apr 2001. Such changes to the existing shelter code are meant to accommodate greater flexibility in the design of the building. SCDF has also allowed the floor area of sky-rise garden balconies under URA rules to be discounted from a flat's GFA (Gross Floor Area) when computing minimum household shelter sizes; as well as the use of prefabricated shelter walls.

4. Can the ventilation openings be covered up completely?

   The ventilation openings in the household shelters can be partially covered up by removable aesthetic or architectural finishes. However, at least 25% of the aggregate area of the ventilation openings have to be kept uncovered. This will allow some fresh air to get to anyone who is inadvertently trapped inside the shelter.

5. If there is a fire in the dwelling unit, can a household shelter be used as a refuge?

   Occupants must not seek refuge in household shelter in the event of a fire because it is not designed for such emergencies. Instead, occupants should quickly evacuate from their apartments and move downstairs to the safety of open ground, away from the fire.

Public Education on CD Shelters

1. Will residents be taught how to use shelters during emergencies?
   

   Household shelters in HDB flats are actually storerooms strengthened to function as bomb shelter during a war. During peacetime, the shelters may be used by residents for their own purposes, although most employ them as storerooms. When war is imminent, the SCDF will step up its public education programme to advise residents on what to do to prepare their shelters. Basically they have to empty their shelters to create space for people to seek refuge in, and also to completely close off the ventilation openings.

   In addition, SCDF will advise residents on other preparatory measures, such as bringing in essential household items into the shelter (such as telephones, radios, battery-operated torch-lights, important personal documents, water and medicine etc). The public will also be educated on the shelter occupation procedures.

   As for public shelters, a total of 5 exercises were conducted for the population since 1988, as follows:

• Tiong Bahru MRT station - 7 Feb 1988
• Lavender MRT station - 24 Sep 1989
• Braddell MRT station - 13 Jan 1991
• Newton MRT station - 10 Jan 1993
• Tiong Bahru MRT station - 15 Sep 1996
  
  In addition, Shelter Open House cum CD Exhibition events were conducted in Feb 2000 and more recently in Feb 2003. The Feb 2003 Shelter Open House involved four MRT public shelters along the new North-East Line and two HDB public shelters. Such programmes were conducted to serve as part of the continual process of sustaining public awareness on shelter provision and familiarising the population on the use of public shelters during a war situation, and also familiarise CD volunteers and grassroots leaders in assisting to convert and man the shelters.

2. Where can I learn more about CD Shelters?
   
   Click on the link to learn more about emergency shelter procedures.
   
   
3. Where are the nearest public shelters to my home?

   Click on the link to find the location of the nearest public shelters.

4. What is SCDF doing to help people staying in homes without shelters?
   

   The CD Shelter Act 1997, requires new flats and houses to be built with household or storey shelters. This requirement is based on several important considerations:

• During war, shelters must be very quickly accessible to residents as the warning time may be very short.
  
• Experience from the Middle East shows that people risk being injured or killed when trying to seek shelter that are some distance from their homes.
  
• Shelters should be fully utilised during peacetime to make them cost effective. Therefore shelters are not purely designed and built to be dedicated shelters, but to serve peacetime functions as well.
  
• As the household shelter is integral to the dwelling unit, separate maintenance is not required.

Because household and storey shelters are integrated into the overall design of the building, the SCDF recognises that retrofitting shelters into existing dwelling units would greatly inconvenience owners, incur disproportionately high costs and create layout difficulties. Hence the CD Shelter Act only requires shelters for new dwelling units. However, owners wishing to build shelters in their houses can seek the SCDF for advice.

For residents in dwelling units without shelters, the SCDF will advise them how to improvise some form of cover in their homes by using household and furniture items that are available. While this does not offer the same degree of protection as a shelter, such improvised cover will nonetheless offer a reasonable degree of protection against flying debris and glass splinters - generally the major cause of casualties in any blast incident. In fact, as mentioned earlier, it is definitely safer to stay at home under some form of cover than to be out in the open trying to get to a public shelter during an attack.

5. Which are the professional bodies that the SCDF consult regarding household shelters, and how often are such forums held?
   
   During the drafting of the shelter legislation and specifications for household shelters, SCDF consulted major developers and key professional bodies such as the SIA, IES, ACES and REDAS. Later, a separate feedback session was held to present the draft documents to the same bodies, major developers and architectural firms to obtain their feedback as well.

   A discussion group comprising representatives from SCDF, HDB, BCA, and the above-mentioned professional bodies was initiated in Feb 98 to address issues commonly raised by Qualified Persons regarding the technical requirements for household shelters. At these meetings, case studies on the shelter's layout in various types of housing developments were presented and discussed. In addition, the SCDF and the BCA also compiled examples of architectural designs of household shelters (with case studies and illustrations) to facilitate the Qualified Persons in planning and designing household shelters. This is to ensure the correct interpretation of technical requirements.

   So far, over 10 discussion sessions have been held. After more than 3 years since the implementation of the CD Shelter Act, this discussion forum has stopped. Instead, ample opportunities are provided to raise shelter issues and offer feedback during the bi-monthly FSSD Standing Committee meeting; as well as the quarterly dialogue sessions that the FSSD conducts with the building professionals.

When a building is hit

1. Will the building collapse, leaving the shelters standing on their own?
   
   Even after being hit by a bomb, it is very unlikely that buildings will collapse like a pack of cards to leave the household shelters standing on their own. From engineering studies and tests conducted, plus observations of war torn areas, building damage by weapon effects is usually localised in nature. While several floors of the building may be perforated, thus causing the collapse of the adjacent areas, the building as a whole will remain standing.

   However, it must be noted that while a shelter can give protection in many situations, it is not practical to design a shelter that will give total protection. Should a large enough weapon explode sufficiently close to a shelter, that shelter may be damaged with its occupants amongst the resultant casualties. This is an inevitable risk in a war situation.
   

2. Will occupants be trapped in the shelters of a damaged building?

   The risk of being trapped is minimised because of certain design considerations. For instance, the ceiling outside the shelter is strengthened to prevent debris from blocking the path of egress. The protective steel door is also designed such that it can still be opened despite being damaged. Tests using a typical HDB household shelter have demonstrated that occupants in a sealed shelter can remain inside within tolerable limits for up to 4 hours. This will be sufficient time for the SCDF, which is equipped with the necessary appliances and skills, to mount a rescue of the people from the building.

3. Is there a back-up power supply for the household shelters?

   There is no back-up power supply. However, occupants will be advised to bring along their own battery operated lighting and communication devices when seeking refuge in the shelter.

Cost Considerations

1. Is it fair for owners to pay for the additional cost incurred in building the shelters?
   
   On the issue of who should pay for the incremental cost of building shelters, the basic principle is that owners should bear the cost of their own protection at home. From HDB's experience, the incremental cost attributed to household shelter requirements (such as increased wall thickness, shelter doors etc) is estimated to be about $4,000. This works out to about 4-5% of the selling price of a HDB 4-Room Flat; and 2-3% of a HDB 5-Room Flat (and even less for a private dwelling unit). Given that a typical HDB household shelter is capable of holding 4 persons, it actually does not cost more than $1000 per person. This figure can be regarded as a relatively small one-off up-front lump payment of the premium for assurance of protection in war.