An expert report analyses the impact of pathway widths and constrictions, as well as a time-staggered use of the escape routes on escape times.
Workplace Regulation ASR A2.3, which is currently being updated by the Committee for Workplaces (ASTA), defines the requirements regarding the dimensions of escape routes. By using a number of simulation models in the context of an expert report the impact of constrictions and stairs on escape routes and a time-staggered use of escape routes effects escape times were investigated.
Employers are required to take precautions for their employees’ protection when setting up and operating workplaces to ensure that employees can be brought to safety immediately and rescued quickly in case of danger (section 4, para. 4 of the Ordinance on Workplaces (ArbStättV)). In this context, the configuration of escape routes and emergency exits plays an important role. For this purpose, rule A2.3 of the Technical Rules for Workplaces (ASR), "Escape Routes and Emergency Exits, Escape and Rescue Plan" (Fluchtwege und Notausgänge, Flucht- und Rettungsplan) stipulates the required number, arrangement and dimensions of the escape routes. Some of the requirements included in ASR A2.3 originate from earlier directives. The Committee for Workplaces (ASTA) therefore commissioned a project group with reviewing and updating ASR A2.3.
To support this revision, an expert report was commissioned by BAuA to investigate the extent to which the width of paths, stairs, doors and constrictions influences escape times and what effects a staggered use of escape routes in multi-storey buildings has. In a supplementary study, the interactions between the number of levels, the number of people per level and the width of the stairs were analyzed. The expert report is based on calculations with two independent microscopic simulation models as well as comparative calculations with macroscopic flow models.
One result of this investigation showed that short constrictions on horizontal escape routes barely have any impact on the total escape time or the passage time of individual persons. In contrast, longer constrictions on horizontal escape routes that may exist in real-world scenarios due to furniture in corridors may have a significant influence on escape times. This leads to delays in escape time. The analyses also showed the existence of a constant linear correlation between the width of the escape route and the total escape time. Stairs in the paths of escape routes lead to a deceleration of the passage of people. If an escape route consists of horizontal as well as vertical elements (stairs), constrictions along the corridor, including a compliant door leading to the stairwell, are negligible, as the actual slow-down in the passage of people is caused by the stairs. In multi-storey buildings, from a certain degree of occupancy of the floors, a tailback can occur in the stairwells and the adjoining areas on the floors.
The results are comprehensively presented in a baua: Report. Two editions of baua: Focus summarize the results and explain individual topics. The objective is to use the results of the expert report in order to adapt the current regulations regarding the widths of escape route in ASR A2.3 to the state of the art.