Unions have raised fears that the Government is using a crackdown on whiplash claims to prepare a "secret assault" on injuries at work.
Unite said a consultation launched on Thursday on whiplash claims included proposals to raise the limit for cases in the small claims court for personal injury claims, including workplace accidents, from £1,000 to £5,000.
The union warned that the move to include workplace accidents will deny workers access to justice and could affect litigation on health and safety issues.
Unite general secretary Len McCluskey said: "Despite initially saying the rise in the compensation cap would apply to whiplash claims only, the Government has snuck in plans for it to cover workplace accidents too.
"This smacks of nothing less than a secret assault on workers injured at work by a Government which professes to govern for all.
"The principle of the small claims provisions is that injuries are so minor, and cases so straightforward, as to not need legal representation.
"Patently that is not true of workplace accidents and diseases where the employer and insurance company have substantial resources to defend any legal action.
"As they stand, the plans will price workers out of justice, leaving them unable to recover legal costs and result in workplaces becoming more dangerous and workplace diseases going unchecked.
"I would urge the Government to think again and exempt workplace accidents from these proposals."
Tom Jones, of law firm Thompsons, said: "If they go ahead, these Government reforms will hit injury victims, on the roads and in the workplace, while lining the pockets of car insurer chief executives and their shareholders."