Abstract: The study of sprays of liquid fuels such as diesel can be hazardous and costly. However, by replacing the liquid fuel spray with non flammable liquids such as water can reduce these problems. In this study, the similarity between water and diesel in terms of spray characteristics is studied. The study focuses on the characteristic of droplet size of the sprays by using Phase Doppler Anemometer (PDA) using a spray nozzle with pressure of 50, 100 and 150 kPa. From the results, it is found that the droplet sizes of water and diesel are quite similar and thus water spray has the potential to replace diesel spray in non-combusting research studies.