Many thanks for your patience, it is appreciated. I am now pleased to be able to provide further assistance with your query.
There is no minimum period required before an employee is referred to OH and it could potentially happen even after a day’s absence. The employee should try and remember that OH is there to primarily help them and to ensure that the employer is aware of the full health situation and that they are taking the right steps and implementing the necessary changes/adjustments to help the employee with their work, including return to work. Therefore, try not to view the involvement of OH as a form of penalty or detrimental treatment. Of course, if there are concerns about what they are doing and the information they are providing to the employer, a grievance can always be raised.
You can get a detailed explanation of the grievance process here:
https://www.acas.org.uk/grievance-procedure-step-by-step
In summary, an employee is expected to submit their concerns in writing and send them to their line manager, or whoever is nominated as the person to send grievances to under an official workplace grievance policy.
The complaint should include details of what the grievance is about, any evidence that may exist which is relevant and also what the employee wants their employer to do about this issue.
Once the grievance has been submitted, the employer is expected to arrange a formal grievance hearing, inviting the employee to attend and discuss the nature of their complaint. The meeting is also as an opportunity to ask for further clarification or information, as required.
Following the meeting, the employer will take time to consider all the issues and evidence and then make a decision, communicating it to the employee. If the outcome is not to the complainant’s satisfaction, they can appeal and get a second opinion from a different person assigned by the employer to consider the appeal. Once the appeal is also completed, that brings to an end the formal grievance process and there is no option to escalate it further internally.