The Anaesthetic Gas Scavenging System (AGSS) Project

The 'Anaesthetic Gas Scavenging System Project' is a project that any healthcare professional can carry out in the theatre environment. Operating theatres are energy hot spots that are six times more energy-intense than hospitals as a whole; at least 84% of the carbon footprint of the operating theatre suite comes from energy consumption (in the absence of desflurane use). Over the next year, NHS trusts/boards will, like many of us at home, face steep energy price rises. Inevitably, the cost to run our theatre suites will also rise.

The NHS needs to tackle the energy burden of needlessly maintaining theatres as if they were operating 24/7. This will require a multi-faceted approach but one spoke in the wheel to reduce energy waste is the Anaesthetic Gas Scavenging System (AGSS).

What is an Anaesthetic Gas Scavenging System?

The AGSS is a means to safely remove anaesthetic waste gases from the theatre environment and is therefore designed to reduce staff exposure to inhalational anaesthetic agents. 

How does an Anaesthetic Gas Scavenging System work?

Anaesthetic Gas Scavenging Systems are typically a fan-based system built into the theatre infrastructure. The fans are connected via piped networks to the back of an anaesthetic ventilator, pulling exhaled waste anaesthetic gases through a low-pressure, high-volume system and expelling them outside of the hospital. They are commonly switch operated.

The Anaesthetic Gas Scavenging System Project

AGSS toolThe 'AGSS Project' is a tool that is ready for you, as a member of the theatre team, to use. It will help you to implement a strategy to reduce the operating hours of these devices, ensuring they are on when they need to be and helping to maintain the safety of staff members.  The step-by-step guide will help to show how much CO2e and £ can be saved. If you enjoy collaborative multi-disciplinary projects and want to make a difference to your theatre energy waste then please get involved - and better still, send in your results so we can share the learning more widely. Case studies will be posted shortly - watch this space. 

Download the tool

If there are any questions once you have had a look at the tool, please contact

This AGSS Project is lead by Dr Jason Gandhi, the National Anaesthetic Sustainability Fellow for the Centre for Sustainable Healthcare and The Association of Anaesthetists Environmental Champions, and Dr John Hickman. It was started in 2019 in Bristol by Dr John Hickman and Dr Samantha Shinde.

Resources for further learning