Automatic fire sprinkler systems greatly reduce fire losses and deaths. While sprinklers provide an estimated 75% reduction in death rate within residential structures, they are installed in less than 2% of new U.S. homes. A major impediment is sprinkler system cost, which can be reduced by optimization of the water flux distribution to the burning surfaces. If sprinkler drop size and velocity distributions are known, water flux distributions can be predicted. Existing measurement techniques, however, are incapable of large scale simultaneous measurement of droplet size and velocity, and cannot operate in fire environments.