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Unattended experiments

This guide sets out the minimum requirements for the provision of information when an experiment is left unattended.



It is acknowledged that there is a requirement to leave experiments to run attended including overnight. This guide aims to provide practical information and a recommended template for the provision of information with the experiment to ensure that it can be safely shutdown in the event of an incident and the relevant persons contacted.

This guide applies to all experiments conducted in University laboratories within high risk departments.

This guidance applies to:

  • apparatus and rigs but not proprietary items such as refrigerators, drying ovens, spectrometers etc

  • use of apparatus outside normal working hours including overnight, weekends and holidays

  • those wishing to leave apparatus unattended, including research students, their supervisors, academics, technicians etc


Unattended Experiment

An Unattended Experiment is a laboratory experiment which is left without supervision (person knowledgeable about experiment not present within the laboratory) for a significant period of time; >2hours.

Operational Form

An Operational Form is a form containing all required information to make safe an unattended/overnight experiment in the event of an incident. This should be attached to the equipment/fume cupboard and be up to date.

Responsible Person

The Responsible Person is the person who has setup the experiment and is responsible for its safe setup, operation and shutdown. They are also responsible for ensuring an operational form is completed and displayed when an experiment is left unattended.


1) Department H&S arrangements should include the requirement to place Operational Forms on equipment (including fume cupboards etc.) when experiments are left unattended.

2) The requirement for operational forms to be communicated to all relevant persons.

3) Laboratory risk assessments to identify when unattended experiments are to be carried out and include the need for an operational form as a control measure.

4) The Operational Form must contain the following information as a minimum:

  • name and contact details of responsible person/s

  • main hazards of experiment

  • instructions for safe shutdown of experiment (these should provide sufficient information for any person to safely shutdown the experiment)

  • supervisor permission

5) Operational forms to be placed on/close by equipment/fume cupboards where required and remain up to date (remove old copies promptly). If shutdown requires switching off the power supply, ensure it is clear which switch/plug is connected to the equipment.

Document control

Date of next review: This page is due for review in June 2023 as part of the review process for the University's Laboratory safety standard.


If you have any questions, please contact us.

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