David
Health surveillance for what??

This is a question asked quite often and there is no solid reply. However a few things need to be considered:

1. For what reason are you undergoing health surveillance? If it is because you work with hazardous agents - noise, chemicals that require HS then the employees under HSWA need to comply with a reasonable management request.

2. Do the employees fully understand why they are being asked to undertake it? In my lengthy experience most people refuse purely because they do not understand what is expected of them or what is going to be done to them and why.

If you have put in place a good quality communication session with questions and answer sessions I am of the strong belief you will get very few refusing.

Most are concerned about the following:
the security of their medical records
if the surveillance is being used to make them redundant etc etc

Ensure you are doing it becuase it is required and you make good use of the data. Just because you have a policy does not make it the right thing to do - risk assessments, COSHH assessments, noise, vibration etc should highlight it too.

The most important thing is then to act on any advice you are given - so if they identify people whose hearing is diminishing then you need to invetigate, look at the risk assessments and act.

Irrespective of the materials worked with/to be worked with, and contracts, all people have the right to refuse medical care/inspection.
That they may, in certain circumstances, be dismissed for refusal is not that relevant.
The same way that they can refuse to sign the (inevitable) consent for their gp records to be made available to their employer which usually accompanies the consent for medical surveillance (in the same way that many (about 40% so far) are refusing to allow their health records to be stored centrally for access by several million public servants).
Of course, you MAY have valid reasons for surveillance, or it may just be a fishing expedition (as so many are now)
You may also like to consider the cost and security implications of medical surveillance, which go way beyond the initial examination and should allow for the 40 year storage of such records, secure storage.
Of course, your provider for the examination may also require consent separate from your companies if they are to access, store or use the records.

http://www.nationalarchi.../sched_health_safety.pdf

Not forgetting the Human Rights Act....