Over the winter months, many people use their gas and electric boilers more than usual, which can highlight potential faults, and wear and tear that would not usually be seen during the rest of the year.
As a result of this, inspections are an essential part of keeping people safe during this time of year, and in some unfortunate cases, an inspector may deactivate a boiler and attach a notice to it, a process known informally as “red tagging”.
This can be concerning for many people, partly because of the worry about having an unsafe component in their house, but also because they will not be able to use their boiler until it is repaired, or in some rare cases, replaced.
However, it is important to know why a boiler might receive a red tag, what it means for you and the process for what happens next.
- The Reality Of Red Tagging
What is known as red-tagging, often called such because historically a red tag is attached to the boiler itself is part of the Gas Industry Unsafe Situations Procedure.
The first step undertaken by a Gas Safe engineer is to assess any potential faults with your boiler and the potential risks of continued use, which they will explain clearly and concisely, as well as answer any questions that will naturally emerge from this.
Typically, they will identify a fault and be able to repair it there and then, but if that is not possible, they will follow the next step of the GIUSP, which classifies the boiler fault with one of three titles, identified with a sticker.
- Not to Current Standard (NCS) – These are for safely operating boilers that are working but not currently operating to the standards that are expected for a boiler. They will remain on but the homeowner will be informed of what is needed to meet those standards.
- At Risk (AR) – These are faults that can potentially cause a dangerous situation in the future but are not an imminent hazard. They are subsequently labelled “do not use” and should be turned off.
- Immediately Dangerous (ID) – These are faults that mean that if the fitting is left connected to a gas supply could potentially constitute an imminent threat to life, and should be physically disconnected from the gas main, capped off and labelled “do not use”.
Contrary to popular belief, registered Gas Safe engineers do not have the right to turn off appliances without the permission of the homeowner, although they would report this situation, which may lead to an emergency service provider coming in who is entitled to disconnect and label any immediately dangerous fitting.
The emergency service provider (typically the company that provides gas to your area), has the legal entitlement to enter your property and make the situation safe.
- What Types Of Fault Are Immediately Dangerous?
The types of faults that could be deemed as worthy of the red tag include many of the more obvious examples of a major fault, such as obvious gas leaks, rust damage, blocked/malfunctioning vents, a gas metre that isn’t working, a cracked heat exchanger and missing parts.

