In its latest weekly incident summary the Mine Safety Unit said a longwall shearer remote went missing from its remote cradle at a NSW coal mine.

The remote was left on longwall by night shift near the bret by tray.

In other incidents a number of notifications for methane levels greater than 2.5% by volume have been reported from underground coal mine operations.

Industry should ensure they put in place adequate ventilation controls for gas levels when carrying out maintenance on their gas drainage plants, the Mine Safety Unit said.