Employees caught smoking at work or in their company car could face fines of £50 under proposed government regulations on smoking in the workplace.
Workers or visitors who are caught smoking will receive a £50 fine under the proposals which are currently under consultation, which drops to £30 if it is paid within 15 days, said law firm DWF.
However, employees who do not pay their fine could be fined up to £200 and get a criminal record under the laws which prohibit smoking in all enclosed or partially-enclosed workplaces.
Company cars are also included in the clampdown, unless the vehicle is used by only one driver, or it is a convertible and the roof is open, said the company.
Associate with DWF, Sarah Clayton, said: "The rules in their current format represent the toughest measures yet to combat smoking at work. Employers need to consider how they would implement the regulations throughout company premises and vehicles to ensure they can comply with the law."
Employers, meanwhile, will have to display a No Smoking sign or face penalties of £200, said the company.
Those who are deemed to have failed to take reasonable steps to prevent smoking could face fines of up to £2,500.