Stairways Fire Escape Routes

A stairway should be of sufficient width for the number of people who are likely to use it in an emergency and it should not normally be less than 1 metre wide. However, a narrower one may be adequate if you are sure that only a few people, who are familiar with the stairway, will use it. Where more than one stairway is provided, you should assume that the widest one may be unusable as a result of the fire. This means that the remaining stairway(s) will need to provide a satisfactory escape route for everyone present.

There may be no need for you to discount the widest stairway where each stairway is reached through a protected lobby. Certain other compensatory features, such as sprinklers or smoke control systems, may also be considered. Stairways should normally be protected by fire-resisting partitions and fire-resisting, self-closing doors (except toilet doors) and lead directly to a way out of the building. An unprotected stairway may, however, be suitable in workplaces of low or normal fire risk, provided that:

• the stairway links no more than two floors and those floors are not linked to another floor by an unprotected stairway; and
• it is additional to that required for escape purposes; and
• no escape route from a dead-end situation on an upper floor passes the access to such a stairway.

People should not have to pass through a protected stairway to reach an alternative stairway. Where this cannot be achieved, a stairway may be by-passed, for instance by using doors connecting adjacent rooms. In such situations the doors should be kept free from obstruction and available for use at all times. A single stairway may be suitable for means of escape in workplaces of low or normal fire risk, provided that people on each floor can reach it within the appropriate travel time (see details of distances earlier in this section).

It also needs to:

• be constructed as a protected stairway and serve no more than three floors above, or one floor below, ground level;
• be accessed, other than at the top floor, by means of a protected lobby or protected corridor;
• be of sufficient width to accommodate the number of people who may need to use it in an emergency; and
• lead direct to open air.

There is no need for you to provide protected lobbies where the workplace is of low fire risk. This also applies to workplaces of normal fire risk, provided that either an automatic fire detection system or sprinklers linked directly into the fire alarm system are installed in the rooms or areas leading directly onto the protected stairway. In small workplaces of low or normal fire risk, unprotected stairways (including a single stairway) may be satisfactory as a means of escape, provided that:

• the stairway provides access between the ground and first floor and/or ground floor and basement only, and an exit can be reached from any part of those floors within the escape times given for single escape routes earlier in this section; and
• access to the stairway is clearly visible from any part of the floor it serves and it exits not more than 6 metres from a storey exit leading direct to open air at ground level.