What to Do If Your Fire Extinguisher Pressure Gauge Is in the Red
When you glance at your fire extinguisher and notice the needle on the pressure gauge is in the red, it’s a clear sign something’s wrong. Whether it’s too low or too high, pressure outside the safe zone means your extinguisher may not function properly in an emergency.
Here’s a simple guide to understanding what the pressure gauge means, what to do if it’s in the red, and how to stay compliant with Canadian fire safety regulations.
What Does the Pressure Gauge Measure?
Most fire extinguishers—especially ABC dry chemical and CO₂ models—are pressurized to force the extinguishing agent out when activated. The gauge measures internal pressure and helps identify whether the unit is still in working condition.
The gauge typically has three zones:
Green: Safe and ready for use
Red (left side): Undercharged or low pressure
Red (right side): Overcharged or high pressure
Some models may also show a yellow “caution” zone, depending on design.
If the Gauge Is in the Red (Low Pressure)
This means the extinguisher is undercharged, and may not discharge properly—or at all—when you need it. This is most commonly caused by:
Age and natural pressure loss
A slow leak
Accidental discharge or damage to the valve
Exposure to extreme temperatures
What to do:
Do not use the extinguisher.
Mark it as “out of service.”
Contact a certified technician for an inspection.
Most units can be recharged if there is no structural damage.
In Ottawa, all commercial fire extinguishers must be inspected annually. More details are available through the Ontario Fire Code.
If the Gauge Is in the Red (High Pressure)
This is less common but still dangerous. Overcharged extinguishers are typically caused by:
Faulty recharging
Exposure to heat (e.g., near a furnace or in a vehicle during summer)
What to do:
Remove the unit from service immediately.
Store it in a safe area until inspected.
Overpressurized cylinders can rupture and should be handled carefully.
Some high-pressure cylinders may also require hydro testing if there’s concern about internal damage.
Can I Fix It Myself?
No. Fire extinguisher servicing—including recharging or pressure adjustments—must be done by a certified technician using specialized equipment. Attempting to service a unit yourself is unsafe and could void its certification.
You can find certified facilities through Transport Canada’s Requalification Directory.
Fire Extinguisher Service in Ottawa
At Rapid CO₂, based in Ottawa, Ontario, we provide complete fire extinguisher inspections, refills, recharging, and hydro testing. If your gauge is in the red, our technicians will determine whether the extinguisher can be safely recharged or needs to be replaced.
We also offer on-site servicing for commercial clients, and can provide inspection reports to keep your business code-compliant.
For pressure issues, servicing, or testing, call (613)-299-8412.
