Why boilers and pressure vessels must be inspected
Boilers, compressor tanks, gas cylinders, and storage tanks hold large amounts of pressure or hazardous liquids. Corrosion, thinning walls, or a stuck safety valve can lead to an explosion, a leak, or a fire. Inspection and testing confirms that the vessel and its safety devices are still fit for use, before a small defect becomes a major accident.
What we inspect
Boilers
Steam boilers and equipment that produces or uses pressurised steam.
Pressure vessels
Gas storage vessels, process vessels, compressor air receivers, and refrigeration units, above 1 kg/cm² pressure and 2.25 litres volume.
Transport vessels
Cylinders and tanks for carrying pressurised gas.
Storage tanks
Tanks for flammable liquids from 200 litres, and other liquids from 450 litres or above 99 °C.
The risks of neglecting it
Explosion
A vessel that fails to hold its pressure can explode and damage the surrounding buildings.
Hazardous leaks
Leaking gas or flammable liquid can cause fires and pollution.
Production stops
A failed boiler or compressor stops every production line that depends on it.
Stopped by inspectors
Equipment without a valid certificate can be prohibited from use by labor inspectors, bringing work to a halt.
Inspection and testing schedule
| Type | When it is done |
|---|---|
| First | During design and manufacture, before first use, and when installed, altered, or modified. |
| Periodic | Regularly after the first inspection, at intervals set by the vessel type and applicable regulations. |
| Special | After an accident, fire, or explosion. |
| Repeat | When the results of a previous inspection are in doubt. |
Documents to prepare
- Construction drawings and technical data from the manufacturer.
- Material certificates, especially for pressurised plates and pipes.
- Nameplate photo: brand, capacity, working pressure, and serial number.
- Previous certificate and inspection report (periodic inspection).
- Maintenance and repair records.
Site preparation
- Schedule a shutdown if the inside of the vessel needs to be inspected.
- The vessel is emptied and cleaned as directed by our team.
- Water and equipment for a pressure test are prepared if needed.
- An operator or technician accompanies the inspection.
Legal basis
- Law No. 1 of 1970 on Work Safety requires safety conditions for equipment and installations at the workplace.
- The Steam Act 1930 (Stoom Ordonnantie) and its implementing regulations for boilers.
- Minister of Manpower Regulation No. 37 of 2016 on OHS for Pressure Vessels and Storage Tanks.
- Inspections are carried out by an OHS Expert in Boilers and Pressure Vessels appointed by the Minister.
Frequently asked questions
Do air compressor tanks need to be inspected too?
Yes, if their pressure and volume fall within the pressure vessel limits. Send us the nameplate data and we will help confirm.
What is a hydrostatic pressure test?
The vessel is filled with water and pressurised above its working pressure to prove that it is strong and does not leak.
Do operations have to stop?
External inspection can be done while running. Internal inspection and pressure testing require the vessel to be shut down and emptied, so we schedule it with you.
Send us a list of your boilers, vessels, or tanks with nameplate photos through the quote form. Our team will prepare an inspection schedule.
Field documentation
