Anthony — TSSA-Certified G1 Gas Technician
TSSA G1 licence #TBD · 15+ years in gas and mechanical trades · Service area: Greater Toronto Area, Ontario
Last updated: 2026-08-07
What is the difference between a red tag and a warning tag?
A red tag records an unsafe condition and takes the appliance out of service. A warning or advisory tag records something a technician wants documented — a deficiency, a recommendation, a condition to monitor — without declaring the appliance unsafe. The first one stops you using the appliance. The second one does not.
The word "yellow tag" gets used loosely in Ontario. Some contractors use a yellow or amber card for advisory findings, some use it for their own internal deficiency notice, and some do not use one at all. Terminology and colour vary between companies, so the class and wording printed on your card decide what it is — not the colour.
| Tag | Appliance status | Utility involved? | What you must do |
|---|---|---|---|
| Red tag, Type A | Out of service. Gas shut off at the appliance on the spot. | Yes, in the record of the shut-off | Have the defect corrected and verified before it goes back on |
| Red tag, Type B | May run until the expiry date printed on the tag | Yes, after the date passes | Correct and verify before the printed date |
| Warning / advisory / deficiency tag | Stays in service | No | Address the noted condition on your own timeline |
How do I tell which one I have?
Read the card. A red tag says so in its title and carries a class — Type A or Type B, usually as a checkbox or printed word — plus the cited defect and the issuing contractor's registration details. Type B tags carry an expiry date. Type A tags generally do not, because the gas is already off.
- Look for the words on the card: is it titled as a red tag, or as a warning, advisory, or deficiency notice?
- Look for a class. Type A or Type B appears on a red tag and nowhere else.
- Look for an expiry date. A date on the card points to a Type B red tag.
- Check the appliance itself. If the gas cock at the appliance is closed and secured, you are dealing with a Type A situation.
- Photograph both sides of the card before anyone touches it, then read the cited reason.
Does a warning tag ever become a red tag?
Yes, and it is common. A warning tag records a condition that has not crossed the safety threshold yet. Corrosion progresses, a marginal draft becomes a failing draft, a small leak grows, and the next technician who tests the appliance is looking at a different result than the last one did.
Treat an advisory finding as a scheduled repair rather than an optional one. Correcting it on your timeline in September costs less and is far easier to book than correcting it as a Type A shut-off in January.
Can a home inspector or a utility employee red tag my appliance?
A red tag comes from a certified gas technician working for a TSSA-registered contractor. Utility field staff attending for a gas odour or emergency call can shut off gas and leave documentation, and that shut-off is real regardless of what the paperwork is called.
A home inspector is not a gas technician and cannot issue a red tag or clear one. An inspector's report can recommend that a gas appliance be evaluated, and that recommendation often leads to a real inspection that does produce a tag — but the report itself is not a tag.
Who can remove each type of tag?
A red tag is cleared by a TSSA-registered contractor after the cited defect is corrected and verified. It does not have to be the company that issued it — you can hire any registered contractor, and doing so does not invalidate the tag or restart anything.
A warning or advisory tag has no formal clearance process, because the appliance was never taken out of service. Once the noted condition is corrected, get the correction on an invoice. That invoice is your record, and it is what a buyer's inspection or an insurer will ask for later.
How we handle it
Send photos of the card, front and back, and a TSSA-certified G1 technician will tell you what you are actually holding and what it obliges you to do. If it is a red tag, we correct what is in scope on site and coordinate vetted specialists for anything outside it until the tag is cleared. If it is an advisory, we will say so instead of selling you an emergency.
Frequently asked questions
Is a yellow tag the same as a red tag?
No. A red tag records an unsafe condition and takes the appliance out of service. A yellow, amber, or advisory card is typically a deficiency or warning notice that leaves the appliance in service. Colour and terminology vary between contractors, so go by the class and wording printed on the card rather than its colour.
Can I keep using an appliance with a warning tag on it?
Generally yes, because a warning or advisory tag does not take the appliance out of service. It still records a real deficiency, and those conditions tend to worsen, so treat it as a scheduled repair rather than something you can ignore indefinitely.
How do I tell if my tag is Type A or Type B?
It is printed on the tag, usually as a checkbox or a printed word, along with the cited defect. Type B tags carry an expiry date; Type A tags generally do not, because the gas has already been shut off at the appliance. If the gas cock at the appliance is closed and secured, you are in a Type A situation.
Can a home inspector red tag my furnace?
No. A red tag is issued by a certified gas technician working for a TSSA-registered contractor. A home inspector can recommend that a gas appliance be evaluated, and that recommendation often leads to an inspection that produces a tag, but the inspection report itself is not a tag and cannot clear one.