Incentive to bypass protective devices

Assessment matrix

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Figure: Example assessment of the incentive to bypass a protective device
Source: IFA


Approximately 37% of all protective devices on metalworking machines are bypassed by defeating. This substantially increases the potential hazard and the likelihood and severity of accidents, and has already resulted in fatal accidents. Reliable statistics, data and facts on the subject of "bypassing of protective devices on machinery" appeared for the first time in 2006 in the HVBG Report of the same name.

The bypassing of protective devices can be avoided completely only if machines are designed such that tampering presents no advantages, i.e. no incentive exists. Whether this (ideal) situation has been reached on a machine or not is an issue of crucial importance to the designers, purchasers and operators of machines.

The IFA presents an assessment matrix by means of which the incentive to bypass protective devices on machines can be evaluated. For practical use, an Excel table is available by means of which the benefits gained from the bypassing of a protective device can be identified. The section of the assessment matrix entitled "Corrective measures" contains recommendations for measures which can be identified, from the results obtained, for the phases of a machine's design, purchase and operation.


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New Internet portal:
Advice to avoid bypassing of protective devices for manufactureres, merchants and operators

Further information


Christian Werner, M.Sc.

Division 5: Accident prevention, Product safety

Tel: +49 2241 231-2653
Fax: +49 2241 231-2234