What is the minimum clear width required for all existing exit stairs?

The minimum clear width required for all existing exit stairs is 915 mm. This dimension is established in building codes to ensure safe and efficient egress during an emergency. The rationale behind this requirement is to provide adequate space for occupants to evacuate quickly and safely, especially in situations where panic may lead to crowding.

Having a width of 915 mm helps to mitigate the risk of bottlenecks, allowing more people to exit simultaneously. It is an essential aspect of building safety regulations that aims to protect life and promote rapid evacuation in the event of a fire or other emergencies. While other widths may vary based on specific design considerations or new constructions, the 915 mm standard specifically addresses the needs for existing structures where modifications might be limited by the prior built conditions.