Objective To provide useful reference data on the standardization of utility and control procedure of plastic film isolators. Methods To explore a useful and appropriate procedure of assessment of internal environment in isolators according to the national standards. Results The measurement results demonstrated that those parameters can well satisfy the demands of evaluation of the function and feasibility of the plastic film isolators in accordance with the national standards. Conclusion The measurement procedure described in this study may well be used in evaluation of plastic film isolators.