Fire extinguisher hydrostatic testing
A hydrostatic test pressure tests an extinguisher's shell. OSHA requires it every 5 years for CO2, water, foam and wet chemical units, and every 12 years for stored pressure dry chemical and halon units. Stored pressure dry chemical units also get emptied and maintained every 6 years. Published prices for a 5 lb ABC hydro test run from $12 to $35 in the public bids below, and shop prices run from $10.50 plus recharge to a published Tampa Bay range of $75 to $95.
Test intervals by extinguisher type (OSHA Table L-1)
OSHA 29 CFR 1910.157(f) sets the hydrostatic test intervals for workplace extinguishers in its Table L-1. Federal regulation text is public, and the main rows are below.
| Extinguisher type | Test interval (years) |
|---|---|
| Soda acid (stainless steel shell) | 5 |
| Cartridge operated water and/or antifreeze | 5 |
| Stored pressure water and/or antifreeze | 5 |
| Wetting agent | 5 |
| Foam (stainless steel shell) | 5 |
| Aqueous Film Forming foam (AFFF) | 5 |
| Loaded stream | 5 |
| Dry chemical with stainless steel | 5 |
| Carbon dioxide | 5 |
| Dry chemical, stored pressure, with mild steel, brazed brass or aluminum shells | 12 |
| Dry chemical, cartridge or cylinder operated, with mild steel shells | 12 |
| Halon 1211 | 12 |
| Halon 1301 | 12 |
| Dry powder, cartridge or cylinder operated with mild steel shells | 12 |
Source: OSHA 29 CFR 1910.157, Table L-1
The 6 year maintenance for dry chemical units
Between 12 year tests, OSHA requires stored pressure dry chemical extinguishers to be emptied and given the applicable maintenance every 6 years. A recharge or a hydro test restarts that 6 year count. Disposable units are exempt.
Minnesota Department of Health guidance describes the same 6 year step as an internal examination by a trained technician, and adds that full maintenance is also needed whenever an extinguisher is hydrostatically tested.
Nonrechargeable dry chemical units are not hydro tested. Minnesota's guidance says they must come out of service 12 years after manufacture.
Sources: OSHA 29 CFR 1910.157(e)(4); Minnesota Department of Health, Maintenance and Testing of Portable Fire Extinguishers
When a test is needed early, and what happens if a unit fails
OSHA requires a hydrostatic test whenever an extinguisher shows new corrosion or mechanical damage. The test schedule does not cover units that were repaired by soldering, welding or patching, have damaged threads, are pitted by corrosion, or were burned in a fire. A shell that is not fit for testing must be removed from service.
Before the test, the shell gets an internal and external examination. The test uses water: OSHA does not allow air or gas pressure. CO2 extinguishers are tested every 5 years at 5/3 of the service pressure stamped on the cylinder.
A shell that fails, or is not fit to test, must be removed from service and from the workplace. The employer keeps a certification record with the test date, the tester's signature and the extinguisher's serial number until the next test or until the unit is retired.
Source: OSHA 29 CFR 1910.157(f)(4)
Who may perform a hydrostatic test
OSHA requires hydrostatic tests to be done by trained people with suitable test equipment and facilities.
Some extinguisher cylinders are US Department of Transportation (DOT) specification cylinders. Testing those takes a requalification identification number (RIN) issued by the DOT's Pipeline and Hazardous Materials Safety Administration (PHMSA). A RIN approval letter that one Florida service company posts says the number covers hydrostatic requalification of listed cylinder types at that one location only.
Texas: a company holding a DOT RIN can get a Type C Hydrostatic Testing Registration from the State Fire Marshal's Office. A technician with a Type B (FEL-B) license may test only DOT non-specification extinguishers; DOT specification units must go to a Type C registered company.
Utah: rule R710-1 issues separate license types for hydrostatic testing, each requiring a DOT RIN, and the general servicing license (Type 4) excludes hydrostatic testing. Utah also bars servicing an extinguisher that is due for a hydro test until it has passed.
Sources: OSHA 29 CFR 1910.157(f)(1); PHMSA RIN D133 approval letter, posted by Serviced Fire Equipment (St. Petersburg, FL); Texas Department of Insurance, State Fire Marshal's Office, extinguisher licensing; Utah Administrative Code R710-1
Published hydrostatic test prices
Some shops price the test alone and add the recharge. Others quote test and recharge together, so compare like with like.
| Business or buyer | Location | Item | Published price |
|---|---|---|---|
| Safety Flare, Inc. | Albuquerque, NM | 12 year hydro test, ABC or BC | $10.50 plus recharge |
| Safety Flare, Inc. | Albuquerque, NM | 5 year hydro test, CO2 | $36.50 |
| Louisiana Fire Extinguishers | Lafayette, LA | Hydrostatic test | $25 |
| FireEx Services | Minnesota (651 area code) | 12 year maintenance with hydro test | $30 per unit plus $90 trip charge |
| Serviced Fire Equipment | Tampa Bay, FL (published area range) | 5 to 10 lb ABC hydro test | $75 to $95 |
| Serviced Fire Equipment | Tampa Bay, FL (published area range) | 5 to 10 lb CO2 hydro test | $85 to $115 |
| City of Tulsa bid: Marmic Fire & Safety Co., Inc. | Tulsa, OK | 5 lb ABC hydrotest | $25.00 |
| City of Tulsa bid: Marmic Fire & Safety Co., Inc. | Tulsa, OK | 10 lb ABC hydrotest | $35.00 |
| City of San Antonio bid: Hotshot Hydro | Seguin, TX | ABC hydrostatic test | $65.00 |
| City of San Antonio bid: Hotshot Hydro | Seguin, TX | CO2 hydrostatic test | $95.00 |
| Chatham County bid: Armor Fire Protection, LLC | Garden City, GA | 5 lb ABC hydrostatic test | $35.00 |
| Chatham County bid: Armor Fire Protection, LLC | Garden City, GA | 20 lb CO2 hydrostatic test | $175.00 |
| Garrett County contract: Fire Protection Products, Inc. | Garrett County, MD | 5 lb ABC hydro test | $12.00 |
| UW-Madison contract: Summit Fire Protection | Madison, WI | CO2 hydro test, stamp and recharge | $30.00 |
| City of San Antonio bid: Hotshot Hydro | Seguin, TX | 6 year maintenance | $45.00 |
| Safety Flare, Inc. | Albuquerque, NM | 6 year maintenance | $5.00 plus recharge if needed |
Sources: Safety Flare, Inc., Fire Extinguisher Service Pricing (PDF); Louisiana Fire Extinguishers, fire extinguisher services; FireEx Services, Services Pricing; Serviced Fire Equipment, Hydrostatic Testing for Fire Extinguishers; City of Tulsa Purchasing, bid summary TAC 181H; City of San Antonio, draft bid tabulation IFB 5894; Chatham County Purchasing, price sheet 25-0153-3; Garrett County, contract 23-1005-F price schedule; UW-Madison Purchasing, contract 21-5105 pricing
Sources and dates
- OSHA 29 CFR 1910.157, Table L-1, read October 8, 2026https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.157
- Minnesota Department of Health, Maintenance and Testing of Portable Fire Extinguishers, read October 8, 2026https://www.health.mn.gov/facilities/regulation/engineering/lscfireext24.pdf
- PHMSA RIN D133 approval letter, posted by Serviced Fire Equipment (St. Petersburg, FL), read October 8, 2026https://servicedfireequipment.com/wp-content/uploads/2026/05/dot-hydrostatic-testing-approval-rin-d133.pdf
- Texas Department of Insurance, State Fire Marshal's Office, extinguisher licensing, read October 8, 2026https://www.tdi.texas.gov/fire/information-fire-extinguisher-registration-license-test.html
- Utah Administrative Code R710-1, read October 8, 2026https://adminrules.utah.gov/api/public/getHTML/uac-html/a40b3abc-0873-4e14-8542-9df17346e345.html
- Safety Flare, Inc., Fire Extinguisher Service Pricing (PDF), read October 8, 2026https://www.safetyflare.net/uploads/1/2/1/9/121921318/fire_extinguisher_service_pricing.pdf
- Louisiana Fire Extinguishers, fire extinguisher services, read October 8, 2026https://louisianafire.com/fire-extinguishers/
- FireEx Services, Services Pricing, read October 8, 2026https://www.fireexservices.com/pricing
- Serviced Fire Equipment, Hydrostatic Testing for Fire Extinguishers, read October 8, 2026https://servicedfireequipment.com/hydrostatic-testing-fire-extinguishers-guide/
- City of Tulsa Purchasing, bid summary TAC 181H, read October 8, 2026https://cityoftulsa.org/media/31304/bid-summary-tac-181h.pdf
- City of San Antonio, draft bid tabulation IFB 5894, read October 8, 2026https://webapp1.sanantonio.gov/RFPFiles/IFB_5894_202507100423160.pdf
- Chatham County Purchasing, price sheet 25-0153-3, read October 8, 2026https://cms.chathamcountyga.gov/api/assets/purchasing-website/1ff60954-35a8-40aa-a13e-c55a96e6c583?download=0
- Garrett County, contract 23-1005-F price schedule, read October 8, 2026https://www.garrettcountymd.gov/sites/default/files/Contract%20Attachment-Fire%20Protection%20Products.pdf
- UW-Madison Purchasing, contract 21-5105 pricing, read October 8, 2026https://www.bussvc.wisc.edu/purch/contract/lists/5105pricing.pdf
Common questions
How often does a fire extinguisher need a hydrostatic test?
Every 5 years for CO2, water, foam, wet chemical and stainless steel dry chemical units, and every 12 years for stored pressure dry chemical and halon units with steel, brass or aluminum shells, per OSHA Table L-1.
Is the 6 year maintenance the same as a hydro test?
No. Every 6 years a stored pressure dry chemical unit is emptied and examined inside. The hydrostatic test, a pressure test of the shell, comes at 12 years. A recharge or hydro test restarts the 6 year count.
How much does a hydrostatic test cost?
Published prices for a 5 lb ABC hydro test range from $12 (Garrett County, Maryland contract) to $35 (Chatham County, Georgia bid). Safety Flare in Albuquerque lists $10.50 plus recharge, and a Tampa Bay shop publishes $75 to $95. CO2 tests are listed from $30 to $175 depending on size.
Who can hydrostatically test a fire extinguisher?
Trained people with proper equipment. DOT specification cylinders need a facility with a DOT requalification identification number (RIN). Texas and Utah also require a state hydro test registration or license.
Do disposable extinguishers get hydro tested?
No. Nonrechargeable dry chemical units are removed from service 12 years after manufacture instead.