Some areas are still affected.
People in Galway city, Oranmore, Salthill and Claregalway can now resume using gas, as the warning for those areas has now been lifted.
Gort, Loughrea, Craughwell and Ballinasloe remain unaffected by this issue and may continue to use gas.
However several towns are still affected, including Tuam, Headford, Ballinrobe, Claremorris, Castlebar, Westport, Crossmolina and Ballina.
Gas Networks Ireland say that customers should make sure that all appliances are switched off before turning the gas supply on.
Further instructions on how to do this are available here.
Gas Networks Ireland crews continue to work on the remaining affected areas to remove the odourless gas from the network. It says its primary objective is to restore gas to all affected customers in the Galway and Mayo regions as quickly as possible, while ensuring at all times that safety is first priority.
New information in relation to the resumption of gas to other affected areas, as the result of this incident, will be advised as soon as they become available.
Customers with any concerns may contact its Customer Care line on 1850 200 694. Customers who suspect a gas leak or smell gas in any part of the country should always call GNI’s 24 hour emergency line on 1850 20 50 50.