Reducing coal loss and dilution in our mines is a growing focus in mining efficiency and maximising resource value. Blast damage to coal roof is a significant cause of coal loss and dilution in mines across the world. Typically, when a Geologist is modelling a coal roof surface, touch coal records from production drillers are used to support existing exploration data. Touch coal is recorded when a drill rig intercepts the coal roof during normal production drilling operations. The operator records the depth at the point of intersection on a drilling log. To minimise blast damage we implemented a novel technique: Measure While Drilling. The Measure While Drilling process makes use of data sets obtained via production drill rig sensors, which measure a variety of drilling parameters, including rate of penetration (ROP). This technique enables the Mine Geologist to produce short-term coal models with vastly increased resolution, enabling the precise identification of coal roof and floor when compared with acquired survey data. The implementation of Measure While Drilling at Daunia Mine has significantly reduced surface blast damage while enabling a reduction in coal roof standoff. This has resulted in greater coal recovery and removed blast induced coal dilution from our site. Measure While Drilling technology has also been demonstrated to improve the speed of uncovering coal by better fragmentation of the overburden material. The Daunia trial demonstrated a production dig rate efficiency increase of 10%, in releasing the coal for mining. This ability marks a major advance in the efficiency of coal mining, by releasing coal resource quicker to mining and providing the Drill and Blast team the opportunity to better fragment overburden material, reducing hard dig and hard toe areas across the site. CITATION: Partridge, J R L, 2019. Measure while drilling: a case study at Daunia Coal Mine, in Proceedings Mining Geology 2019, pp 7280 (The Australasian Institute of Mining and Metallurgy: Melbourne).