fire · Free · Open Source · MIT

Evacuation Time (RSET) Calculator

Required Safe Egress Time. Based on NFPA 101 / BS 9999 / SFPE Handbook. Results shown with the full formula so you can verify. Zero signup, zero tracking, zero data sent to a server — all calculation is client-side.

Inputs
RSET — Required Safe Egress Time
2.5 min
Pre-movement
60s
Travel
25s
Flow through exits
64s
Raw JSON result
{
  "preMovementS": 60,
  "travelS": 25,
  "flowS": 64,
  "rsetS": 149,
  "rsetMinutes": 2.5,
  "regulation": "NFPA 101 / BS 9999 / SFPE Handbook"
}
Overview

About the Evacuation Time (RSET) Calculator

Required Safe Egress Time (RSET) per NFPA 101 / BS 9999. Combines pre-movement time + travel time + flow-through-exits time. Required in fire risk assessments for occupied buildings above certain thresholds.

Formula
RSET = pre-movement + travel + flow
Regulation

NFPA 101 / BS 9999 / SFPE Handbook

How to use

Step-by-step: using the Evacuation Time (RSET) Calculator

  1. 1
    Enter occupants, travel distance, exit widths, pre-movement time.
Who uses this calculator

Used by safety professionals worldwide

Regulation citations

Authoritative sources

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