Companies reopening on Monday who fail to adhere strictly to the national return to work safely protocol could face closure.
The Irish Congress of Trade unions says businesses cannot cut corners and compromise on workplace safety.
Workers will have to keep a distance of two metres from others and the social distancing requirements will also apply to any customers.
According to the roadmap, which has not yet been confirmed, the next phase will mean that small retail outlets will reopen with a small number of staff on the basis that the retailer can control the number of individuals that staff and customers interact with at any one time.
Large retail shops are expected to be allowed to open from Monday as the Government signs off on entering phase two of the easing of Covid-19 restrictions.
This will exclude stores in shopping centres and they will need to have a ground-level open entrance.
ICTU general secretary Patricia King said that, under the workplace representative infrastructure, the rep is entitled to inform the health and safety authority of any breaches.
Ms King said: "Their role will be to ensure that, on foot of health and safety, all the provisions are being met, and if they are not met that representative is then entitled to feed that information to the Health and Safety Authority.
"The Health and Safety Authority will inspect the place of work and do what is necessary up to and including the closure of the business."