Prevent the defeating of safeguards

Manipulation of a safety door switch using a replacement actuator

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Manipulation of a safety door switch using a replacement actuator
Source: IFA

If hazards associated with machines cannot be eliminated or sufficiently minimised by design, then safeguards are used. Safeguards are designed to protect machine operators from the remaining hazards associated with the machine. However, safeguards are often repeatedly dismantled, bypassed or otherwise rendered inoperable, despite the risk associated with this. Occupational safety experts estimate that safeguards are temporarily or permanently tampered with on a quarter of all machines. This leads to thousands of work related accidents every year that are linked to the defeating of safeguards.

The most common reason for defeating safeguards is due to shortcomings in the machine’s safety concept. If the safety concept is not adapted to allow the machine to be operated with ease, then safeguards are seen as a nuisance. In such cases, the guard makes it difficult, if not impossible, to carry out maintenance work, set up, operate, troubleshoot or clean the machine. This constitutes a strong incentive for people working with such machinery to bypass the safeguard.

Companies that manufacture and operate machinery have a legal duty to ensure that all machinery placed on the market and made available to the public is safe. Machines with a high incentive for defeating are to be considered unsafe and must not be operated due to the increased risk of damage. So the question of whether or not a machine’s safeguards constitute an incentive to tamper with them and, if so, what measures can be taken to reduce this incentive, is therefore relevant to both the machine manufacturers and the companies operating the machines.

  • "Defeating" working group

    In 2008, the Prevention Managers’ Conference set up the Defeating working group. Assisted by trade associations and German social accident insurance institutions, and under the direction of the Institute for Occupational Safety and Health (IFA), the working group develops cross-sector design examples, informative publications and guidance documents in the areas of machine design, operation and standardisation. The results are published on the following website in cooperation with the Defeating working group of the International Social Security Association (ISSA):

  • Tuition modules for accident prevention

    The working group has developed four tuition modules, among others, to be used in safety instructions and training courses. They help lecturers make specialists from machine manufacturing and operation, occupational safety and prevention aware of the problem of defeating and develop concrete approaches to resolve this issue. The tuition modules contain PowerPoint files with explanatory notes. The modules can be used as a whole or in parts, depending on the time available and the level of detail required.

  • Demo model “Defeating of interlocking guards”
    IFA expert Christian Werner using the demo model to explain the problem of manipulation

    IFA expert Christian Werner using the demo model to explain the problem of manipulation
    Source: IFA

    At several stations, the IFA’s demo model shows different types of interlocking devices for movable guards. The model clearly demonstrates how these can be defeated on the one hand – and how they can be protected against defeating on the other hand.

    The demo model is intended for use in seminars from institutions of the German Social Accident Insurance . Here the seminar participants can learn about the different types of interlocking devices, defeat safeguards and learn how to identify defeated safeguards more easily. They also learn which technical measures can be taken in each situation to prevent interlocking devices from being defeated.

    The demo model can also be loaned to companies as part of a training course on the subject by an IFA expert. Please feel free to contact us in this regard.

  • App for determining the incentive to bypass safeguards

    The IFA has developed a web application that can be used to determine incentives to bypass safeguards on machines. The result from the web application is intended to help with the identification of measures that lead to a reduction in the bypassing of safeguards and a subsequent decrease in the accident risk resulting from such actions.

    The web application and additional information can befound here.

    Start MaSeM

  • Teaching material for vocational schools

    The DGUV’s Education and Health school portal provides teaching materials for vocational schools in order to raise trainees’ awareness about the defeating of safeguards at an early stage.

    The trainees expand their technical competence in handling safeguards on machines. Participants are made aware of the issue and encouraged to take responsibility for the safe use of machinery through informative written material, discussion of accident examples and independent risk analysis on a machine.

    DGUV Education and Health school portal:, web code: lug1001361

  • Survey on the defeating of safeguards

    To assess the current extent of the problem, the IFA conducted a survey between 2020 and 2022. In an online survey, close to 850 occupational safety professionals were asked for their opinion on the current level of defeating.

    The survey results indicated that defeating in companies is tolerated by supervisors more often than expected. The survey results also showed a statistically significant correlation between tolerance by management and the frequency of defeating and subsequent accidents.

    The survey results can be found here:, Webcode: p022557

Further information

New Internet portal:
Advice to prevent defeating of protective devices for manufactureres, merchants and operators


Stefan Otto, B.Sc.

Accident Prevention: Digitalisation - Technologies

Tel: +49 30 13001-3525
Fax: +49 30 13001-38001