There are different types of controls: initial control, periodic control and audit control.

Controls reduce the risk of serious injuries

The purpose of the checks is to establish that the pressurised device is safe to use. Together with the monitoring and lifetime record, the checks provide an indication of the condition and state of the equipment so that damage does not occur when the equipment is in operation.

For example, an accredited inspection body has equipment to see damage inside materials that is not visible on the surface. Even invisible damage can be an indication that something is not right or is happening to the device.

If a pressurised device is used without being checked, there may be damage that goes undetected. This damage can cause the device to break or explode, which can have devastating consequences.

Which devices are subject to inspection requirements?

All pressurised devices belonging to class A or B must be checked. In order to determine whether a device is subject to inspection requirements, you must first know what type of pressurised device you are using (pipeline, pressure vessel, vacuum vessel or tank).

Once you have found out what type of device it is, you will find the information needed to classify the pressurised device in the Swedish Work Environment Authority's provisions and general guidelines (AFS 2023:11) on work equipment and personal protective equipment - safe use, Chapter 9, Sections 25–35.

The tables for classifying pressurised equipment into classes A and B have a number of exceptions. You must therefore read all the subtitles of the tables. All limits in the tables are lower limits. This means that if a value lies exactly on the line, the device belongs to the lower class.

Gas cylinders, portable fire extinguishers and breathing apparatus cylinders must also be checked. Gas cylinders are checked according to the Swedish Civil Contingencies Agency (MSB) regulations.

The employer is responsible for ensuring that checks are carried out

The employer is responsible for ensuring that the control requirements are followed at the workplace. In Chapter 9 of the provisions on work equipment and personal protective equipment, you will find the information you need to determine the correct classification of the device.

The classification in turn indicates whether the device must undergo checks according to Chapter 10 of the provisions on work equipment and personal protective equipment.

• Class A. Requirements for initial inspection, audit inspection and recurring inspection in the form of operational tests. In addition, there are requirements for regular inspections in the form of internal and external examinations.
• Class B. Requirements for initial inspection, audit inspection and recurring inspection in the form of operational tests.

The inspection may only be carried out by accredited inspection bodies

Inspection of pressurised devices may only be carried out by an accredited inspection body. Swedac (the Swedish Board for Accreditation and Conformity Assessment) is the authority that accredits inspection bodies in Sweden, i.e. approves them.

Examples where control is needed

Water tanks on concrete trucks

The Swedish Work Environment Authority has noted that accidents have occurred with concrete trucks equipped with water tanks intended for cleaning the gutters and tools used in concrete work.

The water tank is emptied by pressurising it with air from the vehicle's compressor and is therefore considered a pressurised device Therefore, these water tanks must comply with the Swedish Work Environment Authority's provisions on the use and control of pressurised devices.

Inspection requirements for the water tanks

These tanks, which contain both air and water, are often of such a size that they belong to class A or B. This means that they must be inspected by an inspection body before they can be used. During the inspection, the inspection body checks, among other things, that the safety equipment functions satisfactorily and protects against overpressure.

Risk of damage due to corrosion and high pressures

The risks with this type of pressurisation are that the tank can be affected by corrosion when it is emptied and refilled with fresh water. This could lead to damage to the tank and the tank bursting.

It is also important to check that the external connections do not have too high pressures. This may result in the safety valve and relief line not being able to relieve the pressure and the tank's maximum permitted pressure being exceeded.

Read more about inspections of certain pressurised devices:

Professional boiling vessels

Tanks