What are the main escape routes

The optimum function of a main escape route is based on various basic requirements. The type of use and layout of the workplace play a decisive role here.

In addition, planning focuses on the maximum possible number of people present - this determines the required number, arrangement and dimensions of the escape routes.

The length of a main escape route, i.e. the shortest distance from the starting point to the emergency exit without taking into account the room equipment, is a key characteristic. A first escape route must be as short as possible. The maximum length depends on the fire risk.

Examples of the maximum length of the main escape route:

• Rooms without / with normal fire risk: up to 35 m
• Rooms with increased fire risk and automatic fire extinguishing equipment: up to 35 m
• Rooms with increased fire risk without automatic fire extinguishing equipment: up to 25 m
• Rooms with a risk from explosive substances: up to 10 m

Exceptions are possible in accordance with ASR A2.3 and the risk assessment. The actual length of the walkway must not exceed 1.5 times the maximum permissible length.

The dimensional specifications for main escape routes are divided into height and width. A first escape route should have a clear height of 2.10 m and not be less than 2.00 m wide. Similar regulations apply to passageways and doors along the main escape route: The recommended height is 2.10 m, but at least 1.95 m.

The above dimensions also apply to areas with functional elements such as overhead door closers.

The maximum number of people who have to use the main escape route in the event of danger determines its width. Installations and equipment such as fire extinguishers, wall projections or door elements must be given special consideration in the planning, as they can temporarily restrict the available space.

The minimum clear widths for the first escape and rescue route are defined in ASR A2.3 for new and existing buildings. An overview can be found in the following blog article "How wide must an escape route be?".