It's illegal to sell or burn smoky coal in Cavan and Longford towns from today.
As of this morning, the smoky coal ban is in place in 13 more towns across Ireland. The Department of Climate Action extended the ban for environmental and health reasons.
However the coal can still be used in areas outside of restrictions.
People are being urged to make sure the fuel they're buying or burning is labelled as smokeless.
Some fuel suppliers have questioned the need for the ban and say it will impact on their businesses.
Tommy Sheahan from North Pole Fuels in Cavan told Shannonside Northern Sound he doesn't see how it can be enforced.