ISO/TR 16738:2009

Overview

ISO/TR 16738:2009 is a technical report from ISO on fire‑safety engineering that provides engineering‑level information about methods for evaluating the behaviour and movement of people during fire emergencies. It is aimed at supporting performance‑based design by explaining how to quantify and manage occupant behaviour - especially escape behaviour - so designers and regulators can compare Available Safe‑Escape Time (ASET) with Required Safe‑Escape Time (RSET) and apply an appropriate margin of safety. The report covers buildings and other built environments (including tunnels and ships) but does not address the use of lifts (elevators) in emergency evacuation.

Key topics

• ASET and RSET concepts - Basis of performance‑based life‑safety design and how to compare available versus required escape time.
• Pre‑travel activity and travel times - Methods to estimate recognition, response and movement times; how these phases combine to form total evacuation time.
• Design behavioural scenarios - How to define qualitative scenarios that describe occupant characteristics, building features and fire dynamics for RSET derivation.
• Effects of fire effluent, smoke and heat - Guidance on tenability, willingness/ability to move through smoke, and impacts on walking speed and toxicity.
• Flow and exit modelling - Calculation of flow time, exit capacities and multi‑compartment/multi‑storey escape strategies.
• Detection and warning - Annex guidance on detection-to-warning timing and how alarm strategies affect RSET.
• Data annexes - Informative annexes provide response‑time distributions, default RSET variables, travel speeds, flow rates, and worked examples (including international comparisons).

Practical applications and users

ISO/TR 16738:2009 is intended for:

• Fire‑safety engineers performing performance‑based design and evacuation modelling
• Building designers and architects assessing life‑safety strategies
• Regulators and code authorities reviewing engineered solutions and alternative compliance approaches
• Risk assessors and emergency planners who need quantifiable occupant behaviour inputs for evacuation or tenability analyses

Typical uses:

• Deriving RSET inputs for evacuation simulations or hand calculations
• Defining design behavioural scenarios and margin‑of‑safety requirements
• Evaluating the impact of smoke, heat and toxic effluent on occupant movement and tenability
• Integrating occupant behaviour with fire dynamics and intervention analyses

Related standards

• ISO/TR 13387 (parts) - occupant behaviour and life‑safety guidance
• ISO 13571 - evaluation of tenability / exposure to fire effluent and heat
• ISO 13943 - fire safety vocabulary

This report is informative (non‑mandatory) and intended to be used in conjunction with the referenced ISO guidance when developing or reviewing performance‑based fire‑safety designs.