| In order to further investigate the stability,carrier and air disinfection of peracetic acid-glutaraldehyde compound disinfectant,a series of tests were carried out according to “Veterinary Disinfectant Identification Technical Specification”.B.subtilis(ATCC 9372)spores and E.coli(8099)carriers killing effect,chemical and microbiological method to detect the stability of the stock solution and diluent disinfectant and the use stability of diluent,static weightlessness method to measure metal corrosion,using S.albus 8032 indicator bacteria,aerosol spray method determine the air disinfection effect and minimum dosage,interaction between spray disinfection and ammonia were tested.The results showed that:(1)The B.subtilis spores carrier was acted for 60 min by the disinfectant,which was 256 times dilution,the killing rate was 100%.The E.coli carrier was acted for 10 min by the disinfectant,which was512 times dilution,the killing rate was 100%.The results shows that the lowest effective bactericidal concentration of the disinfectant on the carrier of B.subtilis spores was 0.39%,the shortest effective time was 60 min.For the E.coli carrier,the minimum effective bactericidal concentration was 0.195%,and the shortest effective action time was 10 min.(2)54℃/14 d 、 37℃/90 and 25℃/12.5 months were sealed and stored away from light in the disinfectant stock solution.The average reduction rate of peracetic acid content was 14.93%,30.28%,and10.17%,respectively.The killing log value were 5.50,4.70 and 5.72 when acted on the B.subtilis spores.The results showed that under the condition of sealed and dark at room temperature,the shelf life of the disinfectant was more than one year and less than two years.The E.coli was acted for 7.5 min by the disinfectant which was stored at 25℃ for 30 days in a concentration diluent,the killing log value was more than 5.After the common concentration disinfectant used repeatedly 75 times,the E.coli carrier was acted for 15 min by the disinfectant,the killing log value was more than 3.After the common concentration disinfectant used continuously 14 days,the E.coli carrier was acted for 15 min by the disinfectant,the killing log value was more than 3.The above application conditions met the standard of disinfection.It shows that the common concentration disinfectant can be stored at room temperature for 30 d,and used repeatedly 75 times and used continuously for 14 d.(3)After 72 hours immersion at room temperature,the corrosion rate of the maximum use concentration(sterilization concentration)and the common concentration(disinfection concentration)of this disinfectant on stainless steel,copper,carbon steel,aluminum and iron was between 0.01 and 0.1.It shows that the highest use concentration and common concentration of this disinfectant are mild corrosion to stainless steel,copper,carbon steel,aluminum,iron.(4)The effect of spray disinfection raised with the increase of spray dose and action time.After the spray dosages of common concentration disinfectant with 15 m L/m3 or 20 m L/m3 for 30 min or 20 min,respectively,all the killing rate of S.albus was more than 99.90%.It shows that the minimum dosage of this disinfectant for air spray disinfection is 15 m L/m3.(5)After the spray dosages of common concentration disinfectant with 15 m L/m3 for 30 min,the removal rate of ammonia was 32.7 %,meanwhile,the killing rate of S.albus was more than 99.90%.When the concentration of ammonia≥48.57 mg/m3,after 30 minutes of action,the killing rate of S.albus was less than 99.90%.It shows that the minimum dosage of air spray disinfection is 15 m L/m3 512 times diluted disinfectant,which can reduce the ammonia concentration while achieving disinfection effect;but when the ammonia concentration≥48.57 mg/m3,it could reduce disinfection effect. |
