Ramps and guarding of stairs etc

The categories for the use of ramps are similar to those set down for stairways, the width not being less than that required for the same category of stair.

• The slope of any ramp should not be more than 1 in 12.

• There should be no permanent obstructions placed across any ramp.

Vehicle ramps or areas of buildings accessible by vehicles are required to have barriers in order to protect people.1 Document K2/3 in the Regulations provides guidance on barriers and is shown in Figure 10.2.

Figure 10.2 Vehicle barriers (ramps, etc.)

mon requirement is that buildings in excess of 18.3 m height have fire alarm systems and that adequate access exists for the fire brigade to reach lifts and stairs.

1984 Act: Means of Escape above 6 or 4.5 metres. This provision covers escape stairs where there is a storey over 6 or 4.5 m above ground in specific buildings, namely hotels, boarding houses and hospitals.

10.3 Means of escape in case of fire (general matters under Building Regulations)

The National Building Regulations make general provisions on access and exit matters and these can be enumerated as follows:

• 1984 Act, Section 24: Access and Exit. This section governs access and exit in public buildings and places of public assembly as well as those licensed for entertainment, music and dance. The fire authority has to agree the details: disputes can be determined by the Magistrates' Court.

• 1984 Act, Sections 6 and 7: Deposit of Plans. Sections 6 and 7 require deposit of plans that show the intended arrangement and stipulate that plans shall be updated to show what has been finally built and agreed.

• Local legislation. Many local authorities have created special powers relevant to building control and these should be checked. Under these local provisions there often exist extra safety requirements for basement garages, e.g. the lobby approach to stairs. Another com-

10.4 Buildings of excess height and excess cubical content

Such buildings are still governed within inner London by Section 20 of the London Building (Amendment) Act 1939-The provisos affect buildings higher than 30 m, or 25 m if the area of the building exceeds 930 m2, or for large trade buildings over 7 100 m3- The means of escape in case of fire under Section 20 are still controlled by Sections 33 and 34 of the 1939 Act- The requirements are more stringent than those in Code of Practice 3 clause IV or in BS 5588-2

10.5 Mandatory rules for means of escape in case of fire

The mandatory rules are prescribed in Part B of Schedule 1 to the Building Regulations (1991), known as Approved Document B1. These relate to fire compartments, sprinklers, etc. and should be checked carefully.3 As they do not apply to the actual design of stairs they have been omitted in this edition.

Indication of these rules in practice are given in Chapter 3 (Figures 3.4a and 3.4b). The numbers refer to clauses in Approved Document B1. Full information can be obtained from the latest edition of The Easiregs prepared by Henry Haverstock for Building Design.4

• For building heights not greater than 11 m (measured from top floor to the lowest ground level adjacent to the building).

A typical vertical core is shown in Figure 10.4e. Lobbies cannot be used as through routes to other stairs unless subdivided by fire doors.

10.6 Escape from flats

Ground and first floor flats are treated as houses, assuming occupants can jump from first floor windows. Flats above second floor are subject to mandatory rules as summarized in Figures 10.3a and 10.3b. Protected hallways within flats are limited to 9 m in length. Flats planned more spaciously will need alternative means of escape to balconies and secondary stairs, which can be external but are limited to 6 m unless protected from snow and ice. Internal escapes should terminate at ground level.

10.7 Escape from offices (BS 5588: Part 3, Codes of Practice for Office Buildings)

The horizontal escape is limited by travel distances (Figures 10.4a-c) which refer to all levels (ground and upwards). The number of exits is calculated by occupancy, see Figure 10.4d.

Escape stairs have to be duplicated in the following circumstances.

• Buildings of three or less storeys.

10.8 New technology

Today's technology for fire protection includes smoke detectors, linked to automatic door release and which overcomes the annoyance of the lobby approach to stairs in high-risk locations. Today the stair enclosure doors will operate on a self-closing device whilst the second set of doors will be released by electromagnets. A further change is the acceptance of positive air pressure within the escape routes and stairhalls to expel smoke that may enter from adjacent accommodation. The Loss Prevention Council is a useful authority on up-to-date procedures.5 They publish a number of guides and advise on fire-fighting facilities.

10.9 Access and facilities for disabled people

Although recommendations for disabled people were included in the previous Regulations, they were not obligatory, but under the 1998 revision to Approved Document M new regulations came into force on 25 October 1999. When dealing with access requirements for disabled people reference should also be made to the Disability Discrimination Act 1995.

Figure 10.3a Corridors and lobbies (escape from flats)

Figure 10.3b Flat plans (escape from fats)

Figure 10.4 Escape from offices

(d) Table for number of escape routes

Figure 10.4 Escape from offices

From the viewpoint of construction work, after 2004 service providers will have to ensure that there are no physical features which make it unreasonably difficult for disabled people to use their services. For example, this may involve installing accessible entrances, lifts, etc., in existing buildings. The Regulations apply to:

• Extensions to existing buildings (but not to dwellings, which are excluded from Approved Document M) if the extension has a ground storey. The extension must comply with the requirements of Approved Document M but there is no obligation to bring the existing building up to standard. If the extension is capable of being independently approached and entered from the boundary of the site, then it should be treated as if it were a new building.

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