Katy, I have only just come across this thread so I hope I am not too late with advice as I work in the field of industrial safety.
You do not state in your opening post whether it is the actual working practices (example'- new equipment or procedures being introduced) that has changed or whether it is your role that has changed within established procedures and practices. The foregoing is very important in how best to proceed with your problem.
If new equipment or working procedures have been introduced then under legislation sufficient risk assessments should have been carried out and hazard reduction measures introduced if those risk assessments did not come within laid down perimeters.
Your first step, should the above be the case, would be to ask to see those risk assessments in the company of someone who understands how they are compiled and what the parameter results should be. There are strict regulations in regard to manual handling in a workplace environment and that is what I feel needs to be looked at in your case.
If the management refuses to allow you to see the risk assessments then you need to apply for a grievance hearing as allowed for under current legislation. Should you be required to undertake such action then having someone from a trade union to accompany you to such a hearing will be imperative. Those persons are known as Formal Companions and have to be allowed on a workplace site whether a trade union is recognised by an employer or not.
Should it be that your role has changed within current established working practices and equipment used, then your problem is far less straight forward. There should still be risk assessments for the various tasks in place, and those assessments should be reviewed each year. However, your employer may well argue at any grievance hearing that the working tasks have not changed, but that you are no longer fit enough to carry out those tasks.
In the above, an " occupational compatibility interview" should be carried out by your employer to assess your fitness for the tasks you are employed to carry out. Should that interview conclude that you are not any longer compatible with that work then it becomes very complicated. How long you have been employed by the company in that work will become very prevalent, and in that, whether your employer has to seek alternative work for you within the company.
In the above, you would most definitely need professional assistance by way of a trade union full-time organiser or employment solicitor as such circumstances then enters the realms of the Equalities Act etc.
Hope this helps Katy and please post as to how the matter progresses.
