The Director-General of the Construction Industry Federation (CIF) says it is not a requirement for workers to wear masks unless they are in an enclosed environment.
Construction sites reopened today, with 150,000 workers returning to building under guidelines for physical distancing and hygiene.
Tom Parlon has been reacting to concerns by some workers over social distancing measures in operation as sites reopen.
He insists the issue is being taken seriously and some people are jumping to conclusions.
Mr Parlon says: "It is not a requirement and it is not recommended by the HSE at the moment and we have said that the wearing of masks in construction is in line with HSE guidance.
"Now they are talking about now in enclosed situations that you wear a face shield or a facemask but it is not a requirement and that is why people are jumping to conclusions.
"You are not required and I have heard experts debate up and down on different things whether you should or not but it is not a requirement to wear a mask."
Mr Parlon's comments come as the government has been warned that "cop on" is not a policy for keeping workplaces safe.
Business Minister Heather Humphreys has said that the Health and Safety Authority will have the power to close businesses that do not adhere to the guidelines.
However, it was today revealed that there are just 67 active HSA inspectors in country, something the Labour Party TD Ged Nash says must be tackled immediately.
Minister Humphreys has not outlined as yet the exact number of new inspectors that will be hired or which departments and agencies supplemental inspectors will be seconded from.