Preventive Maintenance Intervals by Equipment Type (2026 Guide)

Before you set an inspection interval for a fire extinguisher, a stepladder or an office printer, find out where the interval comes from. Some intervals are law. Some are a manufacturer's recommendation. A surprising number are habit that has hardened into something people believe is law.

Where the number comes from matters more than the number itself. Miss a legal interval and you are out of compliance. The manufacturer's figure is a starting point you can move with evidence, while a good-practice interval is entirely yours to set, as long as you can explain why you put it where you did.

This guide covers the equipment you are likely to issue to people or keep in shared pools: laptops and their batteries, printers, projectors and AV, power tools, ladders, portable appliances, fire extinguishers, lifting gear and lab instruments. Vehicles get a brief mention at the end. For how to turn these intervals into a schedule people actually complete, see how to build a preventive maintenance schedule.

Three kinds of interval, and why you should label them

Whenever you record an interval against an item, record its basis alongside it. In an audit, “we test every 12 months because the regulation says so” and “we test every 12 months because we always have” are very different answers, and only one of them survives a follow-up question.

The master table: equipment, typical interval, and where it comes from

Intervals below are as stated by the source linked in each row. Where a source gives a range, the range is shown. Where no fixed interval exists, the table says so rather than inventing one.

Fire extinguishers: the most prescriptive item you own

In the US, if you provide portable extinguishers for employee use, OSHA spells out the cycle. 29 CFR 1910.157(e) requires a visual inspection monthly and an annual maintenance check. Stored-pressure dry chemical extinguishers that need a 12-year hydrostatic test must also be emptied and given maintenance every six years. The hydrostatic test table in the same section sets five years for water and carbon dioxide units and twelve for stored-pressure dry chemical.

NFPA 10, the consensus standard most fire codes adopt, tightens the monthly wording to intervals not exceeding 31 days, and expects a record of who inspected and when, on a tag or electronically.

In the UK the law is less specific about frequency. Article 17 of the Regulatory Reform (Fire Safety) Order 2005 requires fire-fighting equipment to be kept “in an efficient state, in efficient working order and in good repair”. The interval comes from BS 5306-3, under which BAFE notes a basic service should be carried out on every extinguisher at least annually.

Portable appliances: the annual PAT test is a myth

Many UK offices still test every plug-in item every twelve months because they believe the law requires it. It does not. The Health and Safety Executive's own PAT testing FAQ states that the Electricity at Work Regulations require equipment to be maintained to prevent danger, but do not say how or how often, and do not make annual testing a legal requirement.

What HSE offers instead is a set of suggested starting points in Maintaining portable electrical equipment in low-risk environments (INDG236). For desktop computers, VDU screens and photocopiers that are rarely moved, it suggests no user checks, a formal visual inspection every two to four years, and no combined inspection and test at all if the item is double insulated. Earthed (Class I) kit such as kettles gets a visual inspection every six months to a year and a test every one to two years.

On a building site the risk logic runs the other way, and HSE's FAQ uses exactly that contrast: a power tool used on a construction site should be examined more often than a lamp in a hotel bedroom. So if you issue power tools to people working in the field, don't borrow the office intervals.

In the US the comparable rule is a work-practice requirement rather than a test cycle. OSHA 29 CFR 1910.334(a)(2) requires cord-and-plug equipment and extension cords to be visually inspected for external defects before use on any shift, and damaged items removed from service until repaired and tested. Equipment that stays plugged in, in a position where it is not exposed to damage, is exempt until it is moved.

Power tools, workshop kit and PUWER

The UK's Provision and Use of Work Equipment Regulations 1998 apply to everything from a hand drill to a lathe. Regulation 5 requires work equipment to be “maintained in an efficient state, in efficient order and in good repair”, and any maintenance log that exists to be kept up to date.

Regulation 6 adds inspection in three situations, summarised in HSE's inspection guidance:

1. After installation and before first use, and after reassembly at a new site, where safety depends on installation conditions.
2. At suitable intervals where the equipment is exposed to conditions that cause deterioration liable to result in danger. The interval comes from your risk assessment.
3. After exceptional circumstances, such as major modification, known or suspected serious damage, or a substantial change in how it is used.

HSE says inspection results should be recorded and kept at least until the next inspection, and that a digital record is fine as long as it is secure and can be produced for an inspector. Simple pre-use checks normally do not need recording.

In the US, 29 CFR 1910.242(a) puts responsibility for the safe condition of tools on the employer, explicitly including tools employees bring themselves. OSHA sets no interval here, so write your own down and keep to it.

Ladders: daily checks and recorded inspections

Ladders are one of the few items where US and UK practice line up closely. OSHA's 29 CFR 1910.23(b)(9) requires ladders to be inspected before initial use in each work shift, and (b)(10) requires a defective ladder to be tagged “Dangerous: Do Not Use” and removed from service.

In the UK, the LA455 guide produced by the Ladder Association with HSE distinguishes two layers. The user does a pre-use check at the start of the working day and after anything changes, such as a drop; this does not need recording. The employer is responsible for detailed visual inspections at fixed intervals, in line with the manufacturer's instructions, and these should be recorded.

Lifting equipment: LOLER's fixed intervals

Most offices own no lifting equipment. Workshops, theatres, AV teams that rig speakers or lighting, and facilities teams with hoists often do. Under LOLER, HSE says thorough examinations are due every 6 months for lifting accessories and for any equipment used to lift people, and every 12 months for all other lifting equipment. The alternative is an examination scheme drawn up by a competent person, which can set different intervals for specific parts.

Either way, a thorough examination ends in a written report by a competent person. File it against the hoist or sling it describes, where the next person to check that item will see it.

IT and AV equipment: mostly manufacturer territory

Laptops, printers and projectors carry almost no statutory inspection duty beyond the electrical safety points above. Their intervals come from the manufacturer, and increasingly from the device itself.

Laptop batteries

Batteries are the component most likely to force a repair decision mid-life. Apple says its Mac batteries are designed to retain up to 80% of original capacity at their maximum cycle count, which ranges from 300 to 1,000 cycles depending on model. Dell's battery FAQ says typical users will notice reduced runtime after 18 to 24 months, that its batteries carry a one-year warranty as standard, and warns against puncturing or compressing a swollen battery.

For batteries, forget the calendar. Check battery health every time a laptop comes back for reissue, because that is the one moment it is guaranteed to be in IT's hands. And if you find a swollen battery, take the laptop out of service there and then rather than waiting for any schedule.

Printers

HP says many LaserJet maintenance kits should be installed after a page yield of around 225,000, varying with print conditions, and that the printer will usually display a message as parts near end of life. HP also offers a rough rule of every one to two years depending on volume. Page count is the better trigger; the calendar is a fallback for printers nobody reads the counter on.

Projectors and AV

Projector filter maintenance is condition-based. Epson's user guides tell you to clean the air filter when the filter or vents get dusty, when a message appears, or when the filter light flashes. For a projector in a shared meeting room, add a quick filter and lens check to whatever room check already happens. For one that travels with a team, check it on return.

Lab and test instruments: calibration intervals

Calibration is where people most often expect a fixed number and find there isn't one. The joint ILAC and OIML guidance on determining calibration intervals (ILAC-G24 / OIML D 10, 2022 edition) notes that standards such as ISO/IEC 17025 and ISO 9001 require laboratories to manage recalibration intervals, but leaves the interval itself to the laboratory.

According to that guidance, the initial interval is based mainly on a risk assessment, taking into account factors including the measurement uncertainty required, the type of equipment, the manufacturer's recommendation, how heavily and in what environment it is used, and the results of previous calibrations. After that, the interval is adjusted based on what successive calibrations actually find.

If you manage a pool of instruments, give every one its own due date rather than a department-wide one. An instrument that is out of calibration should also be impossible to issue, because work done with it may need repeating once the problem is found.

Vehicles, briefly

Pool cars and vans are often tracked alongside other equipment. In Great Britain a car needs its first MOT by the third anniversary of registration and annually after that. Servicing intervals come from the manufacturer's handbook and are usually mileage- or time-based, whichever comes first. US inspection rules vary by state, so check your own state's requirements rather than relying on a national figure.

Worked example: a 60-person office with a small workshop

Worked example (hypothetical numbers). An organisation in England has 60 staff, 70 laptops, 4 laser printers, 6 meeting-room projectors, 12 extinguishers, 3 stepladders, a workshop with 15 power tools and 1 lifting hoist.

Three of those seven lines have no calendar date at all. They are triggered by something happening to the item, which is a good argument for tying checks to custody events, so that whatever comes back gets looked at before it goes out again.

Checklist: setting an interval you can defend

1. Find the legal requirement first. If one exists, it is your maximum interval, full stop.
2. Read the manufacturer's manual next. Note whether the interval is calendar, hours, pages or cycles.
3. Write down your risk reasoning for anything without a fixed rule: environment, frequency of use, who uses it, consequence of failure.
4. Record the basis against the item, not in a separate policy document nobody opens.
5. Raise the work before it is due, with enough lead time to book a competent person.
6. Block issue of anything overdue. An expired ladder inspection or calibration should stop the item going out.
7. Review intervals annually, lengthening only on evidence and never below a legal requirement.

Keeping intervals attached to the equipment

A well-chosen interval still fails if it lives in a spreadsheet while the equipment moves between people and sites. In Stackroom, a maintenance plan on an asset raises a ticket ahead of the scheduled date, records estimated and actual cost, and puts the item into maintenance status so it cannot be issued until the work is resolved. The maintenance and warranty page covers how plans, tickets and cover sit together on the asset record.

Over time, that service history also tells you whether the item is worth keeping. Something that keeps failing between scheduled services needs a repair-or-replace decision. Shortening its interval won't fix it.

Sources

• 29 CFR 1910.157 Portable fire extinguishers — OSHA
• 29 CFR 1910.23 Ladders — OSHA
• 29 CFR 1910.242 Hand and portable powered tools — OSHA
• 29 CFR 1910.334 Use of equipment — OSHA
• Guide to Fire Extinguisher ITM — NFPA, 2020
• Regulatory Reform (Fire Safety) Order 2005, article 17 — legislation.gov.uk
• Fire extinguisher guidance (BS 5306-3) — BAFE
• Portable appliance testing FAQs — HSE
• Maintaining portable electrical equipment in low-risk environments (INDG236) — HSE, 2013
• Maintenance of work equipment (PUWER regulation 5) — HSE
• Inspection of work equipment (PUWER regulation 6) — HSE
• Thorough examinations and inspections of lifting equipment (LOLER) — HSE
• LA455 Safe use of ladders and stepladders — Ladder Association with HSE, 2021
• ILAC-G24 / OIML D 10 Guidelines for the determination of recalibration intervals — ILAC and OIML, 2022
• Mac battery cycle count — Apple
• Dell laptop battery FAQ — Dell
• HP LaserJet maintenance kits guide — HP
• Cleaning the air filter — Epson projector user guide
• Getting an MOT — GOV.UK