Some US troops travelling to Iraq via Shannon Airport are breaching anti-smoking laws by going into toilets for a cigarette.
Airport workers say the troops have been responsible for the airport being evacuated at least once since the smoking ban was introduced in March.
On at least six occasions soldiers have been found crowding the airport toilets and claiming to be unaware of the smoking ban. However, smoking has not been allowed in that area of the airport for many years.
Shannon Airport's high-tech fire alarm system has been activated several times in recent weeks, resulting in fire and security personnel investigating the source of the emergency.
Troops are segregated from the travelling public during the day by steel shutters. Only at night, when the airport is quiet, are soldiers allowed to leave the secure area and browse around the airport's shops and bar. However smoking is not allowed in these areas either.
Aer Rianta has declined to confirm or deny that the smoking ban is being breached at Shannon, and has refused to answer questions regarding the reported infringements.
A company spokesperson would only say in a two-line statement: "Aer Rianta complies fully with the smoking legislation, and will continue to ensure that the smoking ban applies to all passengers, members of the public and staff members."
Some airport workers are angry at the flouting of the smoking regulations. "There has been no smoking in any of the work areas, and I am not aware of anyone having broken the ban in the restaurant or bars," said one airport employee. "The troops should not be treated any differently to the rest of us."
One airport police officer confirmed that fire and security crews have been alerted six or seven times in recent weeks after smoke alarms in toilets were activated by soldiers.
"We have to try and locate the source of the activation, and until we have done that we don't know whether it is a fire or a false alarm. And if we can't locate the source within 10 minutes, and the system is not reset, the building must be evacuated.
"In fairness, it is a very high-spec fire alarm system, but it may be a bit too high-spec. Ten minutes might not be enough for us to respond and locate the source."
He added: "Several times we have found soldiers smoking in the toilets after coming off a long flight, and it appears that they may not have been told about the smoking ban.
"Troops can be travelling for up to 20 hours without being allowed to smoke, and so the first chance they get they try to have a quick cigarette. You have to feel a bit sorry for them but it is a pain in the neck for us."
A spokesperson for the environmental health services section of the Mid Western Health Board said they have received no formal complaints about alleged smoking at Shannon Airport.