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Fire Extinguisher Services

Fire Extinguisher Hydrostatic Testing

DOT-Compliant Hydrostatic Testing Hydrostatic testing is a safety requirement that verifies the structural integrity of your fire extinguisher cylinders. Required every 5 or 12 years (depending on extinguisher type), this DOT-compliant process ensures your equipment is safe for continued use. During testing, the cylinder is filled with water and pressurized above normal operating levels to check for leaks, deformation, or structural weakness.

Safety Critical

What is Hydrostatic Testing?

Hydrostatic testing is a pressure test required by the Department of Transportation (DOT) and NFPA 10 to verify the structural integrity of fire extinguisher cylinders. Over time, cylinders can develop weaknesses from corrosion, stress, or damage that aren't visible during routine inspections.

During testing, the cylinder is filled with water and pressurized to approximately 1.5 times its normal service pressure. This safely tests the cylinder's ability to contain pressure without the risk of explosion that would occur with compressed air.

Why It Matters

A weakened cylinder can catastrophically fail under pressure, causing serious injury or death. Hydrostatic testing identifies compromised cylinders before they become dangerous.

Legal Requirement

49 CFR and NFPA 10 mandate hydrostatic testing at specific intervals. Non-compliance voids the extinguisher for fire code purposes.

Insurance Compliance

Most commercial insurance policies require proof of current hydrostatic testing. Claims may be denied if testing is lapsed.

Cost-Effective

Testing and recertifying an extinguisher is typically 40-60% less expensive than full replacement.

Hydrostatic Testing Intervals by Type

Different extinguisher types have different testing requirements based on their construction and operating pressure.

5 Years

Water & Foam Extinguishers

Stored pressure water and AFFF foam extinguishers

5 Years

CO2 Extinguishers

Carbon dioxide high-pressure cylinders

5 Years

Wet Chemical (Class K)

Kitchen fire extinguishers for cooking oils and fats

12 Years

Dry Chemical (ABC)

Multi-purpose ABC dry chemical units

12 Years

Halogenated Agents

Halon, Halotron, and FE-36 clean agents

12 Years

Dry Powder (Class D)

Specialized metal fire extinguishers

* CO2 extinguishers require testing every 5 years due to high operating pressures. Consult manufacturing date stamps to determine due dates.

Our Hydrostatic Testing Process

Professional testing performed by certified technicians using calibrated equipment in accordance with DOT regulations.

Empty & Depressurize

Extinguisher is completely emptied and depressurized for safe testing.

1

Fill with Water

Cylinder is filled with water to prepare for pressure testing.

2

Increase Pressure

Pressure is increased to test level (typically 150% of service pressure).

3

Inspect for Issues

Cylinder is inspected for leaks, expansion, or deformation under pressure.

4

Stamp Test Date

Test date is stamped on cylinder for compliance verification and record keeping.

5

Dry & Recharge

Passing cylinders are dried, recharged with fresh agent, and returned to service.

6

Complete Service

Professional Recharge Services

After hydrostatic testing, or whenever an extinguisher is discharged or shows low pressure, professional recharging restores it to full operational status. We recharge all extinguisher types with the proper agents.

ABC Dry Chemical recharge

BC Dry Chemical (regular & Purple K)

CO2 cylinder refill

Class K wet chemical recharge

Clean agent (Halotron, FE-36) recharge

Water and foam extinguisher refill

When to Recharge Immediately

Extinguisher has been discharged (even partially)

Pressure gauge reads below green zone

Annual inspection reveals low agent weight

After 6-year internal maintenance

Following hydrostatic testing

Visible damage to valve or seal

What Happens If a Cylinder Fails Testing?

Cylinders that fail hydrostatic testing must be condemned and cannot be returned to service. We provide:

Proper Disposal

Safe, environmentally compliant disposal of condemned cylinders.

Replacement Options

New extinguisher recommendations matched to your needs.

Documentation

Condemnation records for your fire safety files.

Stay Compliant. Stay Safe.

Don't wait for a violation. Schedule your semi-annual inspection today.

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