Every 12 minutes, someone in the East Midlands reports a smell of gas to the National Gas Emergency Service

• Over 43,500 calls to the national gas emergency number reported of a smell of gas within the East Midlands in 2025
• Rhinologist explains how they are trained to ‘smell gas’ for public safety
• Cadent introduces new ‘gas sniffing’ cars to its networks

For Gas Safety Week (14 – 20 September), Cadent, the UKs largest gas distribution network, is shining a light on one of the industry’s most unusual but vital roles - a specialist team trained to ‘smell gas’ to ensure the odourant levels are correct for public safety.

In 2025, Cadent received more than 43,500 calls to the national gas emergency number from people reporting a smell of gas across its East Midlands network alone – equalling one call every 12 minutes - showing the importance of people recognising the smell and knowing what to do in an emergency.

Natural gas has no smell of its own, so a specially made chemical (mercaptan) is added to give it the distinctive odour people associate with gas. This acts as an important warning sign to let people know a leak may be present and to immediately call the national gas emergency number on 0800 111 999*.

Cadent’s rhinologists are trained to detect whether the right level of mecaptan is present in the gas supply. Getting the balance right is critical, if the odour is too strong, a small leak could be mistaken for a major incident; if it is too weak, people may not detect a gas escape at all.

Edward Fountain is a Lead Rhinologists at Cadent in the East Midlands responsible for ensuring the correct levels of mercaptan are maintained across 40,000km of pipeline in the region.

Across the East Midlands, odourant is injected at gas pressure control sites and entry points. The rhinologists test levels at several different locations, as well as carrying out additional checks at many district governors, where gas pressure is reduced before it reaches homes and businesses.

Edward Foundain said: It’s a serious job with potentially life-threatening consequences if we get it wrong. To ensure we are fully competent, we test ourselves rigorously, completing checks every quarter and before every site visit. We also attend external training every year.

To cross-check our results, we use a portable device known as an odorimeter that presents a controlled mixture of gas and air to the human nose, helping us ensure we meet strict standards.

While the smell of gas remains an important safeguard for customers. Cadent is also investing in advanced technologies alongside its specialist teams to identify gas escapes even earlier.

Picarro, a ‘gas-sniffing’ device fitted to specialist vehicles, is now used across Cadent’s networks to help detect gas escapes before the odour is noticeable to the human nose. In the East Midlands, 67 per cent of the regions gas pipelines have been surveyed using the technology.

Tom Ballard, Head of Safety and Engineering at Cadent East Midlands, said: Innovating our detection processes has safety and environmental benefits, while also helping us prioritise work for our repair and replacement teams.

The device has accurately identified gas escapes in rural areas where it is unlikely residents would have noticed a smell of gas.

By helping the public understand what gas smells like, and by using technology to identify gas escapes before they become noticeable, we can find leaks quicker, reduce disruption and help keep people safe and warm every day.