The safety of people in buildings is the top priority. Careful planning of escape routes is an essential part of any safety concept. The question of when a second escape route, known as a secondary escape route, is required in addition to the main escape route is particularly important. This article provides a comprehensive overview of the requirements and regulations in accordance with the Technical Rules for Workplaces ASR A2.3.
Definition: Second escape route
A secondary escape route, formerly known as a second escape route, is an additional escape route that, like the main escape route, leads outside or into a secured area. Its necessity arises from the risk that the main escape route may no longer be safe to use in certain situations. There can be various reasons for this, which we will look at in more detail below.
When is a second escape route required?
The need for a secondary escape route can arise from various hazardous situations. These include the main escape route being jeopardised by areas with an increased risk of fire or the storage or use of hazardous substances in the vicinity. A second escape route is also essential for hazardous work, for example in installation rooms for steam boiler systems.
The size of the premises also plays an important role. A secondary escape route is mandatory in production, storage or workshop rooms with a floor area of 200 square metres or more. For other workspaces, such as open-plan offices or modern coworking spaces, this limit is 400 square metres.
Particular attention must also be paid to buildings with a high number of people. If the number of people is so high that an orderly escape via the main escape route can no longer be guaranteed, a secondary escape route is mandatory. This applies in particular to places of assembly, schools and day care centres, which are often subject to additional legal regulations.
Technical execution and design
There are various options for the technical design of secondary escape routes. Stairs with straight flights should always be favoured. If this is not possible, spiral staircases, spiral staircases or, in certain cases, even fixed ladders can be used as a second escape route. The choice of a suitable variant should always be made in the order listed above. Moving walkways and escalators are also permitted along secondary escape routes.
The exits can be designed as normal doors, French doors or wicket doors in gates.
Emergency exits in the form of windows, hatches or flaps are also possible. It is important that all doors and emergency exits open in the direction of escape, although sliding variants are also permitted.
The minimum dimensions are clearly defined: Emergency exits in wall openings must be at least 0.90 metres wide and 1.20 metres high. For emergency exits in floor or ceiling openings, a minimum size of 0.70 x 0.70 metres or a diameter of 0.70 metres is prescribed.
Labelling of secondary escape routes
The correct labelling of secondary escape routes is crucial for their effectiveness. Every exit or emergency exit must be clearly labelled. In many cases, it is also necessary to mark the route to this exit, for example if the emergency exit is located in a separate room.
Standardised safety signs are used for this purpose, such as the ‘Emergency exit’ sign (D-E019) or ‘Emergency exit with escape ladder’ (E016).
Second escape route: Possible exceptions
There are situations in which a secondary escape route can be dispensed with. This is possible if additional measures are taken to ensure that the main escape route is safe to use.
In areas with an increased fire risk, for example, these can be measures that prevent the rapid spread of fire and smoke. Even if there are several main escape routes, these can be used as secondary escape routes so that no second escape route is required.
Safe secondary escape route with water mist
The installation of a low-pressure water mist extinguishing system is an innovative technical alternative to the structural second escape route. This solution is particularly interesting for existing properties where subsequent structural changes such as an additional escape staircase would involve considerable expense.
The system offers several advantages: Not only does it allow living space to be extended without costly structural alterations, it also ensures that the existing stairwell can be used safely by all building occupants in the event of a fire.
Good to know: The effectiveness of this alternative is already recognised by the authorities - for example, the authority for urban development and housing of a major German city has confirmed this solution as a verified replacement for a second structural secondary escape route.
First & second escape routes: an investment for greater safety
The planning and installation of secondary escape routes is a complex task that requires both technical understanding and in-depth knowledge of the legal requirements.
Careful implementation of the requirements is essential for the safety of everyone in the building. Given the complexity of the matter and the high level of responsibility, it is advisable to consult experts in order to find the optimum solution for the specific situation.
Investing in well-planned escape routes is always an investment in the safety of the people in the building.