Abstract: This paper discusses the requirements of wind velocity in the test chamber according to the GJB 150A and GB/T 2423 standards, together with analyses of the related purpose and principle of each standard. The approaches in GB/T 2423 for reducing the influence of the wind velocity on the thermal conditions in the test chamber are elaborated. The problems in choosing and using the test chamber in the implementation of the above-mentioned standards are pinpointed.