Objective To test and evaluate the sterilization efficacy of a self-developed formaldehyde
generating terminal sterilization equipment for biosafety laboratories, and to provide scientific support for
its application and promotion.Methods Using Geobacillus stearothermophilus or Bacillus subtilis var.
niger spores as biological indicators, the single-factor variable method was applied to systematically
investigate the effects of three key parameters—paraformaldehyde dosage, sterilization duration, and
ambient relative humidity—on the sterilization efficacy of isolators in biosafety laboratories. Results
Complete sterilization was achieved with paraformaldehyde dosages of 3, 1.5, and 0.75 g/m3
for 6 h of
sterilization. With a fixed dosage of 0.75 g/m3, valid sterilization was attained after 2, 4, and 6 h of
exposure. Under the fixed dosage and duration, qualified sterilization efficacy was obtained at relative
humidity levels of 70%, 75%, and 80%.Conclusion The self-developed formaldehyde generating
terminal sterilization equipment exhibits excellent and reliable sterilization efficacy for isolators in
biosafety laboratories under optimized parameters, and can be used for terminal disinfection and
sterilization in biosafety laboratories.
