More than 300 faulty carbon monoxide alarms bought in Northern Ireland remain unaccounted for.
It is believed about 90 of them were sold in the Newtownards area.
Ards Borough Council has called on anyone who bought a Sensor Safe carbon monoxide alarm, with a serial number, SF80190, to stop using it.
Twelve people have died due to carbon monoxide poisoning in Northern Ireland over the past 10 years.
Carbon monoxide has no smell or taste and so alarms detecting the gas can save lives.
When it enters the body, it prevents the blood from bringing oxygen to cells, tissues, and organs, and can be fatal if victims are not attended to in time.
Sensor Safe Limited, who make the detectors, recalled the product as it was unable to detect the gas.
Anyone with a carbon monoxide detector anywhere in Northern Ireland has been urged to check if their alarm is labelled with the faulty serial number.
If so, they are asked to return it to where it was purchased and if in doubt, to contact Environmental Health staff.