A market survey was conducted to determine the availability of portable, direct-reading ozone (O3) meters with a range of 0.05 to 1 ppm of O3. Manufacturers of suitable meters were requested to submit a meter for an evaluation of its physical and performance characteristics. Characteristics measured include stability, drifts, linearity, response times, and specificity. Physical characteristics evaluated include portability, readout, instruction manuals, and ease of zero and span adjustments. As a result of these evaluations, optimum use techniques and performance and construction standards are recommended. Quality control standards for portable O3 meters are also recommended based upon the evaluation results and current industry practices.