Extend Working Time Regulations to contracted freelance workers

Many industries engage freelancers for lengthy contracts of 50+ hours per week, exceeding the working time limits which standard employees have the right to. I propose that the Working Time Regulations regarding maximum weekly working time and daily/weekly rest become a statutory right for freelancers who are engaged by a company, in keeping with the need to protect the health and safety of workers. Optionally, employers may offer an opt-out for freelancers who want to work in excess of 48 hours/week as overtime.