Test 14: Group behaviour

1. Definition

A room of 15 m by 20 m has a 1 m exit. Group 1 is five adults at the top of the room with no response time. Four walk at 1.25 m/s and the fifth at 0.5 m/s. Group 2 is ten slower adults at 0.2 m/s, spread uniformly in the central part of the room. Group 1 must reach the exit. The test asks whether a group sub-model keeps the group together, as proximity only, when its members differ in speed. A model without group behaviour documents that limitation.

Source: ISO 20414:2020, Test 14, Table 16, pp. 25-26, Fig. 10. This is a paraphrase, not the text of the standard.

Reference: ISO (2020). ISO 20414:2020, Fire safety engineering - Verification and validation protocol for building fire evacuation models. First edition. International Organization for Standardization, Geneva. https://www.iso.org/standard/78348.html (Page numbers are the printed page numbers of ISO 20414:2020 (the copy read is a proof, so numbers can differ by a page in the published edition). ISO states that its tests are examples and that a tester may use different tests that verify the same component equivalently.)

2. Scenario

Scenario figure from the executed notebook.

3. What to expect

The members of Group 1 reach the exit together: their arrival times differ by no more than 10 s. ISO states that 10 s is an arbitrary value chosen to allow a quantitative comparison.

Our criterion: The homogeneous fast group reaches the exit together (spread <= 10 s)

4. Our result

Status: PASS

Test cases of this row

• test_group1_arrives_together: bound: measured <= 10.0 (exit-time spread of the 5 Group 1 agents)

Result figure from the executed notebook.

5. Our implementation

Deviations from the standard:

• Group 1 is homogeneous: all five members walk at 1.25 m/s. ISO’s slow fifth member (0.5 m/s), which is the case that tests group cohesion, is not included. A pass shows that agents of equal speed arrive together and does not show group cohesion.
• Group 2 walks at 0.5 m/s instead of 0.2 m/s.
• The exit is 3 m wide instead of 1 m.
• The threshold of 10 s is ISO’s. Exit time is each agent’s last recorded frame (decision D3). Group 1 is the five agents that start highest in the room. One seed (42) is run.

Model: CollisionFreeSpeedModel

• Test function: tests/vv/test_iso.py::test_group1_arrives_together
• Scenario file: Iso-14-group-behaviour.zip

6. Our notebook

• Executed notebook (HTML)
• Notebook source (.ipynb) on GitHub