Work to rule?
Before you consider going down that road the prime consideration has to be absolute solidarity and the backing of the union.
Otherwise it is easy for the management to "pick off" one or two of the leaders and subject them to a flawed disciplinary process.
This has a variety of benefits for the management: firstly, if they are sufficiently astute they will select a couple of victims who cannot possibly claim racial or sexual or health and safety in their defence. This limits absolutely the power of the Industrial Tribunal to make an award; in addition, even if the Tribunal orders the company to restore the victims to their jobs and to compensate their losses the law is toothless and the decison is not enforcable if the company decide to decline. Which of course they will.
Secondly, the victim, who is immediately suspended, and thereby isolated from his / her colleagues, can be selected for their role, or perceived role, in leading the dispute, thereby, hacking away at the leadership.
Since they will ultimately move through the disciplinary process, frustrated at every turn it discourages their colleagues, who see this, from "breaking ranks"; finally, when the process is exhausted they find themselves out of a job and the company has rid itself, very cheaply, of 2 or 3 "troublemakers".
So you see, in some cases, the Industrial Tribunal and Disciplinary process is actually just another tool the company can use which has absolutely no benefit whatsoever for the workforce.
Unite or perish.