EN
Autoclave
Periodic inspection of steam autoclaves: vessel examination, door safety, safety valve and pressure tests performed by authorised engineers with signed reports.
Autoclave periodic inspection is the regular examination and testing, by authorised engineers, of pressure vessels used for sterilisation, curing or process heating under saturated steam pressure. The vessel body integrity, door locking system and safety devices are assessed. Autoclaves used for sterilisation directly concern public health, so they belong to the equipment group requiring the highest inspection rigour.
What Is an Autoclave and Where Is It Used?
An autoclave is a pressure vessel in which water is converted to steam in a generator and injected into a closed chamber, reaching saturated steam temperatures of 121-134°C under pressure. Main application areas:
- Hospitals and clinics: Sterilisation of surgical instruments and textiles (TS EN 285 large steam sterilisers, TS EN 13060 small sterilisers).
- Laboratories: Medium preparation and waste sterilisation.
- Sterile pharmaceutical industry: Terminal product sterilisation.
- Composite and rubber industry: Press-curing autoclaves.
- Food industry: Canning retorts.
Periodic Inspection Items
The inspection relies on a multi-stage plan that deepens according to the equipment's purpose:
- Body and weld examination: Search for corrosion, cracks and deformation on internal and external surfaces, with non-destructive testing at critical zones.
- Door and locking system: Condition of the gasket, the function preventing door opening under pressure, and safety switches.
- Safety valve and pressure gauge: Set pressure verification, indicator accuracy and periodic blow-down test.
- Pressure test: Hydrostatic test or the proof test foreseen by the standard at its period; tightness verification.
- Process reliability: For sterilisation autoclaves, steam penetration and vacuum leak tests (Bowie-Dick / vacuum qualification) are evaluated together with the mechanical inspection.
Legislation and Standards
Inspections are performed under Law No. 6331 and the Regulation on Health and Safety Conditions in the Use of Work Equipment. The technical basis is the 2014/68/EU (PED) and TS EN 13445 for pressure equipment, and TS EN 285 / TS EN 13060 for sterilisers. Under the regulation, the periodic control is made at least once a year unless otherwise foreseen; the door lock and safety valve are functionally tested at every inspection.
Risk Factors and Operator Recommendations
The common root cause of autoclave accidents is opening the door under pressure or a defective locking system. Therefore, the integrity of the electrical safety chain (door sensor, pressure switch) is verified together with the mechanical lock. Poor water quality creates scale and solidification in the steam generator, reducing steam capacity and accelerating corrosion; regular water treatment and periodic cleaning must be contracted for. In sterilisation processes, load density, pack size and indicator tape verification are inseparable parts of process validation.
Outcome
At the end of the inspection, a signed report with the compliance status and rectification proposals is issued. Autoclave inspections are conducted within our Periodic Inspection of Pressure Vessels service group. For your other equipment you may review our Steam Boiler page and contact us to plan your inspection programme.
FAQ on Autoclave Periodic Inspection
Textile finishing and dyeing autoclaves, rubber vulcanisation presses-cure tanks, wood impregnation and composite autoclaves plus sterilisation kettles; as closed volumes working above 0,5 bar they fall under the Work Equipment Regulation and pressure equipment rules (PED/TS EN). Criticality is set by working pressure-temperature, cycle count and lid lock type.
The lid lock (pressure interlock): the door must not open while under pressure or before temperature falls — most autoclave accidents happen by hot content dumping and pressure release during lid opening. The control covers mechanical and automation function of the locking mechanism, pressure sensor-alarm-cut chain, safety valve set pressure, gauge and vacuum-temperature program limits; a taped-out lock is a life risk.
Visual-corrosion examination of shell-lid-gasket-groove, thickness measurement (UT) where needed; pressure proof at 1,5 times working pressure, verification of lid lock-block function under pressure and at cycle end; safety valve-fusible plug, gauge calibration, automation program-recipe limit-alarm record checks, heating-steam jacket-pump-mechanical audit, earthing-bonding and electrical panel safety, plus steam-water line hardware control.
A yearly engineer examination with proof test (five-yearly hydrostatic cycle where the code requires) is the minimum regime; on high-cycle or chemically aggressive autoclaves the interval is risk-based shortened. The report carries gasket, lock cam-shaft, sensor and pressure switch replacement periods and the operator's pre-cycle lid check instruction. A door with a faulty lock must never return to service before repair-approved verification.