Rank: Forum user 
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Please can I ask the forum for advice on the following
'Functional tests of devices such as emergency stops should be carried out on a regular basis and inspection of the general condition of the work equipment and the safety devices (such as guards) should be carried out before each shift starts.'
We have always gone with daily tests of e-stops but would welcome advice on whether it is necessary on all equipment?
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Rank: Super forum user 
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So you are exercising the safety function of the emergency stop daily, that is once per 24 hours, 5 days per week? So, around 245 times per year. Now I'm not sure that you realise, but now sefety components such as e-stop buttons have what is known as a MTTFd, that is mean time to dangerous failure, along with a B10d vallue which is a number of operations until it is expected that they may fail to danger. So, if you are applying 245 potentially unnecessary operations per annum to the components then the MTTFd will be reached quicker, thus you are actually increasing the likely hood of a dangerous failure... One needs to be very careful of blanket assumptions and testing regimes. With an E-Stop you would not only be applying the operation to the head, but the actuator, the electrical contacts, any processing devices such as safety relays, and the output functions, or actuators e.g. the power relays controlled by the safety relay. You should be taking a fundemental look at the systems of the machine and evaluating whether daily testing is appropriate in conjunction with the safety system validation of the equipment you have.
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Rank: Forum user
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Thanks Paul
That certainly makes sense and has been a concern of mine. Do you know where I may get more information or is it a case of seeking more information from the manufacturer of each piece of equipment? is there any general guidance on this matter?
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Rank: Forum user
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During previous employment in manufacturing plants, e-stops were test daily, if not at the beginning of each shift. Whilst I can see Paul's point I would not want to have to explain to a judge following an accident that we didn't test them as we didn't want to wear them out.
Edited by user 22 January 2018 10:01:20(UTC)
| Reason: Typo
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Rank: Forum user
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Below from the PUWER ACOP, indicates that a pre-use check and an inspection are different, an inspection is concerned with 'safety-related parts', so could that be taken as evidence that you're over-testing the E Stop? 81 Inspection does not normally include the checks that are a part of the maintenance activity although certain aspects may be common. For the purpose of this regulation, inspection does not include a pre-use check that an operator makes before using the work equipment. While inspections need to be recorded, pre-use checks do not.
89 As part of an inspection, a functional or other test may be necessary to check that the safety-related parts, for example interlocks, protection devices, controls etc are working as intended and that the work equipment and relevant parts are structurally sound, for example non-destructive testing of safety-critical parts. The need for any testing (for example non-destructive testing of safety-critical parts) should be decided by the competent person who determines the nature of the inspection.
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