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Water you can use near live electrical equipment

Water Mist Portable Extinguishers (A:C Rated)

Amerex · Badger Canada & United States $$ · No reliable public figure — get quotes

Deionized water discharged as a fine mist, rated for ordinary combustibles and safe near energized electrical equipment. Used in hospitals, including MRI-compatible versions, and in clean rooms.

Why we like it

  • Leaves only water — no powder contamination
  • A:C rating covers ordinary materials and energized electrical equipment
  • Non-magnetic versions exist for MRI suites

Watch out for

  • Most models have no Class B rating, so they are not for flammable liquids
  • Fewer retail outlets than standard extinguishers — mainly dealers and industrial suppliers
Best for

Hospitals and MRI suites, clean rooms and other spaces where powder contamination is unacceptable.

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 Easy
Installing it Trivial
Living with it Easy
Up front

No reliable public figure — get quotes.

Lead time

Days; MRI-compatible units may need ordering

Time to install

Minutes

How it works

The cylinder holds deionized water. A misting nozzle breaks it into very fine droplets that cool the fire. Because the water is deionized and the spray is broken up, it does not conduct electricity back to the person holding the extinguisher, which is what earns the C rating. Afterward there is only water to deal with.

Who needs it

Healthcare, clean rooms and anywhere powder contamination is unacceptable; selected through the NFPA 10 hazard assessment.

Codes, standards and listings

Canada
Water-based agent extinguishers per CAN/ULC-S554; rating per CAN/ULC-S508; selection under the National Fire Code of Canada.
United States
Water-based agent extinguishers per UL 8; rating per UL 711; selection per NFPA 10.

What the market looks like

Amerex and Badger are the makers most often named. These are sold through fire equipment dealers and industrial suppliers, typically to healthcare and controlled-environment facilities.

Features that actually matter

Deionized water
The reason it is safe near energized equipment.
Fine mist nozzle
Breaks the stream so it does not form a conductive path.
MRI-compatible versions
Non-magnetic construction for MRI rooms, where a steel cylinder would be dangerous.
Water-only residue
No powder to contaminate sterile or clean environments.

What it really costs

Up front
No reliable public figure — get quotes.
Consumables
Recharge with deionized water after use. No reliable public figure — get quotes.
What else you'll need
Bracket and signage.
Over five years
Five annual services plus a 5-year hydrostatic test. No reliable public figure — get quotes.

No public price source was checked; all cost lines need dealer quotes.

How it differs from the alternatives

Versus a standard pressurized water extinguisher
Plain water is Class A only and conducts electricity. Mist adds the C rating.
Versus ABC dry chemical
No powder contamination, but usually no Class B rating.
01

Buying it

Effort Easy

Where: Fire equipment dealers (who also service them) and industrial suppliers.

Lead time: Days; MRI-compatible units may need ordering

For an MRI suite, specify a non-magnetic model explicitly.

02

Installing it

Effort Trivial

Time: Minutes

You'll need: Drill · Wall anchors · Bracket

In MRI areas, use non-magnetic mounting hardware as well.

03

Living with it

Effort Easy

Annual service and a 5-year hydrostatic test.

If not this, then what

  • Clean agent extinguisherResidue-free and also suits electronics; larger units carry Class A and B ratings.
  • ABC dry chemicalBroader coverage including liquids, where powder residue is acceptable.

Caveats

  • No Class B rating on most models.
  • The hydrostatic test interval is.
  • No price source was checked; get dealer quotes.
Our verdict

The right extinguisher for hospitals, MRI suites and clean rooms. Keep something rated for Class B nearby if flammable liquids are present.

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. UL Solutions — Fire extinguisher testing and certification

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

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