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Effective and residue-free — and lethal to anyone inside

Carbon Dioxide (CO2) Total Flooding and Local Application Systems

Firetrace · Kidde Canada & United States $$$$ · USD $20,000–$100,000+ per project

High- or low-pressure CO2 floods an enclosure or blankets a single machine, smothering the fire. It leaves no residue but is lethal at the concentrations used, so it belongs only in normally unoccupied spaces.

Why we like it

  • Residue-free, like the clean agents
  • Local application can protect a single machine such as a printing press or dip tank
  • CO2 is not a PFAS or HFC agent

Watch out for

  • Fatal to people at total-flooding design concentrations
  • Requires lockout valves, odorizers and warning signage
  • Not recommended for occupied spaces
Best for

Normally unoccupied machinery spaces, vaults and industrial process hazards such as printing presses and dip tanks.

Read the full market guide — costs, install effort and alternatives ↓
Market guide

The whole commitment, end to end

What this actually is, what the market looks like, what it really costs, and how much of your time it wants — before you spend anything.

Buying it Hard
Installing it Major project
Living with it Moderate
Up front

USD $4–$8 per sq ft (≈ CAD $5.50–$11); USD $20,000–$100,000+ per project.

Lead time

Weeks for design and installation

Time to install

Days to weeks

How it works

Detection triggers a time delay and alarm, then CO2 is released from high- or low-pressure storage. In total flooding, CO2 is raised to roughly 34% or more of the room's atmosphere — enough to smother the fire and to kill anyone still inside. In local application, nozzles spray CO2 directly onto one hazard, such as a printing press or dip tank, without flooding the whole room. Because of the danger, systems require lockout valves for maintenance, odorizers so a leak is noticed, and warning signage.

Who needs it

Normally unoccupied machinery spaces, vaults and industrial processes, under NFPA 12. Not for occupied spaces.

Codes, standards and listings

Canada
NFPA 12 design; ask for ULC-listed components — ask the distributor for ULC-listed hardware and confirm with the local fire authority.
United States
NFPA 12 design, including lockout requirements; systems UL and FM listed.

What the market looks like

Installed systems sold through authorized distributors and installers; Firetrace (High Pressure CO2) and KiddeFenwal are among the makers. Because it is lethal at design concentration, it is limited to spaces that are normally unoccupied.

Features that actually matter

Total flooding
Fills an enclosure to a smothering concentration.
Local application
Targets a single machine or process rather than the whole room.
Mandatory safeguards
Lockout valves, pre-discharge alarms and time delay, odorizers and signage are part of the system, not options.
No residue
Equipment is not coated or soaked.

What it really costs

Up front
USD $4–$8 per sq ft (≈ CAD $5.50–$11); USD $20,000–$100,000+ per project.
Consumables
CO2 refill after discharge. No reliable public figure — get quotes.
What else you'll need
Lockouts, signage, odorizers and alarm integration.
Over five years
Semiannual cylinder weighing and annual system test. No reliable public figure for service contracts — get quotes.

Per-square-foot and per-project ranges from a US contractor cost guide (getsafeandsound.com), 2025–2026; CAD figures converted from USD at ~1.38 because we found no Canadian source. Get at least two local quotes.

How it differs from the alternatives

Versus inert gas
Both lower oxygen, but inert gas systems are designed to leave a survivable atmosphere. CO2 at design concentration is not survivable.
Versus clean agents
Clean agents are designed for occupied rooms; CO2 is not. Choose CO2 only where nobody is normally present.
01

Buying it

Effort Hard

Where: Not sold to end users — through authorized special-hazard distributors and installers.

Lead time: Weeks for design and installation

Ask how the system will be locked out during maintenance and who controls the lockout.

02

Installing it

Effort Major project

Time: Days to weeks

You'll need: Contractor install

Signage, alarms and lockouts are part of the install and must be complete before the system is armed.

03

Living with it

Effort Moderate

Semiannual weighing of cylinders and an annual system test. Train everyone who enters the space on the alarm and the lockout procedure.

If not this, then what

  • Inert gasGas flooding designed to be survivable for short exposure.
  • FK-5-1-12 clean agentFor enclosures where people may be present.
  • Water mistFor machinery enclosures with a listed design.

Caveats

  • Life-safety hazard: total-flooding concentrations are lethal. NFPA 12 requires lockouts, and our cost source explicitly says it is not recommended for occupied spaces.
Our verdict

Use it only where nobody is normally present, and treat the lockout procedure as seriously as the fire protection. Anywhere people work, choose an agent designed for occupied spaces.

We don't take payment for placement and we don't sell these products. If you think we've got something wrong here, tell us — we'll correct it.

Sources

  1. Safe and Sound — fire suppression system cost
  2. Firetrace

Need this installed or serviced? Find a licensed contractor near you →

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