ISO/TC 92/SC 4/WG 11 - Behaviour and movement of people

The aim of this document is to provide designers with correlations that can be used in performance-based fire safety design to represent the reduction of movement speed of building occupants when walking in an environment with low visibility, which also contains irritants. Different correlations are provided for deterministic analysis and probabilistic analysis. It is recognized that values for visibility and irritant species concentration can be used as performance criteria in performance-based fire safety design. Performance criteria related to visibility and irritant species are not specified in this document. However, it is always necessary to take into account relevant performance criteria when applying this document. For example, an occupant cannot be assumed to continue moving if a performance criterion related to visibility or irritant species concentration is violated in the design calculations. It is also recognized that fire smoke can have an influence on the cognitive processes of occupants during evacuation. This type of influence on cognition is not covered in this document but can be considered if deemed to have a major impact. Fire smoke can also influence behaviour (e.g. occupants changing their movement path if moving into worsening smoke conditions). This type of behaviour change is not included in this document but can be considered if deemed to have a major impact. In some jurisdictions, it is not permitted to include fire smoke in escape routes as part of the fire safety design; this document is not applicable in such situations.

ISO/TS 29761:2015 describes a methodology for the selection of design occupant behavioural scenarios that are severe but credible for use in deterministic fire safety engineering analyses of any built environment including buildings, structures, or transportation vehicles. Occupant behavioural scenarios are linked to design fire scenarios. Guidance on the selection of design fire scenarios and design fires is covered in ISO 16733‑1. The steps in ISO 16733‑1 are followed in this Technical Specification with life safety of the occupants as the single fire safety objective under consideration. ISO/TR 16738 provides information on methods for the quantification of the different aspects of human evacuation behaviour in a design context. One part of that process involves the selection of occupant behavioural scenarios. This Technical Specification provides guidance for that aspect of the evaluation of an egress design. ISO/TS 29761:2015 addresses behaviours that occur after fire ignition and does not deal with behaviours that influence fire ignition.

ISO/TR 16738:2009 is intended to provide information to designers, regulators and fire safety professionals on the engineering methods available for evacuation strategies in relation to the evaluation of life safety aspects of a fire safety engineering design. Information is presented on the evaluation, quantification and management of occupant behaviour, particularly escape behaviour, during a fire emergency. ISO/TR 16738:2009 addresses the parameters that underlie the basic principles of designing for life safety and provides information on the processes, assessments and calculations necessary to determine the location and condition of the occupants of the building, with respect to time. ISO/TR 16738:2009 provides information on methods for the quantification of the different aspects of human evacuation behaviour in a design context. It is intended for use together with the parts of ISO/TR 13387 and associated guidance documents and standards. These provide some of the information useful in performing a life safety evaluation and a means for incorporating the results of the life safety evaluation into the wider aspects of a fire safety engineering design. The use of lifts (elevators) in emergency evacuations is not dealt with in ISO/TR 16738:2009.