1.0 OBJECTIVE
To determine the efficacy of disinfectants.2.0 SCOPE
This procedure is applicable for all the disinfectants used for disinfection at manufacturing plant.3.0 RESPONSIBILITY
QC-Microbiologist4.0 ACCOUNTABILITY
Head QC5.0 ACCOUNTABILITY
Head QCPROCEDURE
5.1 Principle: The disinfectant efficacy is based on the ability to reduce the microbial population by 90% within 15 minutes. Here the known concentration of microorganisms is mixed with the disinfectant of respective concentration. And the recovery of the microorganisms is checked at 5 minutes, 10 minutes, and 15 minutes.5.2 Requirements
Disinfectant solution
Normal saline.
SCDA & SDA
Sterile purified water
Microbial culture suspension of,
Escherichia coli ATCC 8739
Pseudomonas aeruginosa ATCC 9027
Staphylococcus aureus ATCC 6538
Candida albicans ATCC 10231
Enverionmental Isolate
5.3 Method
5.3.1 SET-1: Prepare the 100 ml of the disinfectant solution of the respective concentration as per SOP.
5.3.2 Distribute the diluted disinfectant solution in 20 ml quantities in 4 different sterile test tubes, one tube for each microorganism.
5.3.3 SET-2: Prepare another set of 4 tubes using the 20 ml of sterile purified water, one tube for each microorganism.
5.3.4 To the set 2 add the 0.1 ml of the suspension of the respective microorganism to the respective tube which will give the final concentration of 1x105 cfu/ml to 1x106 cfu/ml. Carry out the10 fold serial dilution of each microorganism up to 10-6 using 9 ml normal saline. And then plate out1 ml of each dilution. To this add 20 ml of sterile molten cooled at 45° C Soybean casein digest agar for bacterial cultures and 20 ml of sterile molten cooled at 45° C Sabouraud dextrose agar for fungi.
5.3.5 To the set 1 add the 0.1 ml of the suspension of respective Microorganism to the respective tube which will give the final concentration of 1x105 cfu/ml to 1x106 cfu/ml same as the set2. Carry out the10 fold serial dilution of each microorganism from the respective tube of set 1 up to 10-6 using 9 ml normal saline after 5 minutes, 10 minutes and after 15 minutes. And then plate out 1 ml of each dilution. To this add 20 ml of sterile molten cooled at 45°C Soybean casein digest agar for bacterial cultures and 20 ml of sterile molten cooled at 45° C Sabouraud dextrose agar for fungi.
5.3.6 Incubate the Soybean casein digest agar plates at 30-35° C for 5 days and Sabouraud dextrose agar plates at 20-25° C for 5 days.
5.3.7 After incubation observe the plates and record the count in the annexure, calculate the % reduction for each Microorganism, record the same.
5.3.8 Acceptance criteria: The respective disinfectant should show the 90 % reduction in microbial population within 15 minutes.
6.0 ABBREVIATIONS
6.1 SOP: Standard Operating Procedure6.2 QC: Quality Control
Get editable documentsView List
Hello Sir ,
ReplyDeleteI read this SOP and found informative. I have one question , as per Guidelines there shall be minimum 3 log reduction for bacteria and 2 log reduction for spore and fungi. As 90% reduction criteria does not meet it. Is there any other reason for putting this criteria?