2 · The Whys & the Standards

The Whys & the Standards – BS vs NFPA

The documents

	UK BS	US NFPA
Maintenance	BS 5306-3: code of practice for commissioning and maintenance of portable extinguishers	NFPA 10: Standard for Portable Fire Extinguishers (ch. 7 inspection & maintenance, ch. 8 hydrostatic testing)
Selection & siting	BS 5306-8: selection and positioning	NFPA 10 ch. 5–6 (same document)
Product	BS EN 3 (and UKCA/CE, Kitemark/BAFE-listed)	UL 711 / UL 299 etc. ("UL Listed")
Law behind it	Regulatory Reform (Fire Safety) Order 2005	OSHA 29 CFR 1910.157 in workplaces, plus local adoption of NFPA 10

Side by side: what's done and when

Task	BS 5306-3 BS	NFPA 10 NFPA
Visual inspection	At least monthly, by the responsible person (site)	Approximately every 30 days, by anyone trained. Recorded by tag or electronically.
Main service	Basic service at least annually, by a competent person	Annual maintenance, by a certified person
Deeper service: water, foam, wet chemical	Extended service every 5 years, including a discharge test	Hydrostatic test every 5 years; internal examination per NFPA 10 table VERIFY
Deeper service: dry powder (stored pressure)	Extended service every 5 years, including a discharge test	6-year maintenance (empty, internal examination, recharge) and hydrostatic test every 12 years
Deeper service: CO₂	Overhaul every 10 years, including a hydraulic pressure test	Hydrostatic test every 5 years
Clean agent / halocarbon	Per manufacturer and BS 5306-3 VERIFY	6-year maintenance; hydrostatic test every 12 years
Records	Service label on the extinguisher + report/certificate to the responsible person	Maintenance tag (month/year, who) + verification-of-service collar after internal exam/recharge + hydro test label
When removed for service	Replace with a suitable spare	Replace with a spare of the same type and at least equal rating

The "What's due today?" decision

British Standard route BS

flowchart TD
  A["Extinguisher on annual visit"] --> B{"CO₂?"}
  B -- Yes --> C{"10 years since manufacture<br/>or last overhaul?"}
  C -- Yes --> C1["OVERHAUL incl. hydraulic test<br/>or replace"]
  C -- No --> Z["BASIC SERVICE"]
  B -- No --> D{"5 years since manufacture<br/>or last extended service?"}
  D -- Yes --> D1["EXTENDED SERVICE<br/>discharge test + internal inspection<br/>+ recharge – or replace"]
  D -- No --> Z

Tip: on a phone, scroll sideways or rotate to landscape.

NFPA route NFPA

flowchart TD
  A["Extinguisher on annual visit"] --> B{"Type?"}
  B -- "Water, foam, wet chem, CO₂" --> C{"5 years since last<br/>hydrostatic test?"}
  C -- Yes --> C1["HYDROSTATIC TEST<br/>+ recharge, new hydro label"]
  C -- No --> M["ANNUAL MAINTENANCE<br/>+ new tag"]
  B -- "Stored-pressure dry chemical,<br/>halocarbon / clean agent" --> D{"12 years since<br/>last hydro test?"}
  D -- Yes --> C1
  D -- No --> E{"6 years since manufacture,<br/>last 6-yr or last hydro?"}
  E -- Yes --> E1["6-YEAR MAINTENANCE<br/>empty, internal exam, recharge<br/>+ verification-of-service collar"]
  E -- No --> M

Tip: on a phone, scroll sideways or rotate to landscape.

Why each step is done

Step	Why
Check it's there and accessible	An extinguisher behind a pallet is no use. Accessibility is the most common real-world failure.
Pin and tamper seal	A broken seal means it may have been partly used. A partly used extinguisher can lose all its pressure.
Gauge in the green	Stored pressure leaks slowly over time. Low pressure means a weak or no discharge. Also tap/check the needle isn't stuck.
Weigh it	Proves the agent is all there. CO₂ has no gauge, so weight is the only way to know it's full.
Hose and nozzle	Insects, dirt and perished rubber block or split hoses. The agent goes nowhere useful.
Internal exam / discharge test	Moisture gets in and powder cakes solid (especially where there's vibration). Corrosion inside can't be seen from outside.
Hydrostatic / pressure test	Proves the shell won't burst. Shells weaken through corrosion, damage and age.
Right type for the risk	A water extinguisher next to a switch room is dangerous. A CO₂ in a small office could suffocate the user.
Labels and records	Proves to the client, the insurer, the fire service and the court that maintenance was done.

Who's allowed to do it

	BS BS	NFPA NFPA
Monthly inspection	Responsible person / their nominated staff	Any trained person (owner's responsibility)
Service / maintenance	Competent person: in practice a trained technician, ideally employed by a BAFE SP101 registered company	Certified person: trained, with the manufacturer's service manual, and certified by an organisation acceptable to the AHJ (some US states require a licence)

Positioning: also part of the annual check

You are not normally designing the layout, but you are expected to report extinguishers that are missing, wrong for the risk, or badly sited.

	BS 5306-8 BS	NFPA 10 NFPA
Max travel distance to an extinguisher (Class A)	30 m VERIFY	75 ft (22.9 m)
Mounting height	Handle about 1.0 m above floor for heavier units, about 1.5 m for lighter ones VERIFY	Units ≤ 40 lb (18 kg): top no higher than 5 ft (1.53 m). > 40 lb: top no higher than 3.5 ft (1.07 m). Bottom at least 4 in (102 mm) off the floor.
Rating system	A and B ratings from BS EN 3 fire tests, e.g. 13A 113B	UL ratings, e.g. 4-A:80-B:C

Key takeaways

Monthly look, annual service: both standards agree on this.
Deeper service: BS = discharge test every 5 years (CO₂: overhaul at 10). NFPA = 6-year internal exam + hydro at 5 or 12 years.
CO₂: BS 10-year overhaul vs NFPA 5-year hydro.
UK ratings (13A) and US ratings (4-A) are not the same scale.

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The Whys & the Standards – BS vs NFPA

#The documents

#Side by side: what's done and when

#The "What's due today?" decision

#British Standard route BS

#NFPA route NFPA

#Why each step is done

#Who's allowed to do it

#Positioning: also part of the annual check

#Key takeaways