1. Objective
To lay down a procedure for microbiological analysis of compressed air and Nitrogen.

2. Scope
This procedure is applicable for microbiological analysis of compressed air and Nitrogen used at factory for manufacturing and testing.

3. Responsibility:
Quality Control and Quality Assurance department.

4. Procedure
4.1 Take pre-incubated SCD broth tubes from the incubator.
4.2 Refer sampling programme for sampling point to be sampled.
4.3 Label the SCD broth with below information:
– Sample location:
– Date:
– Room No.:
– Room location:
– Sampled by:
4.4 Carry the pre-incubated broth tubes with SS test tube stand to the sampling point.
4.5 Disinfect stand and outer surface of tube with 70% IPA.
4.6 Enter the room as per pre-defined entry procedure.
4.7 Open the sampling valve gradually and open the SS cap of the test tube.
4.8 Hold the cap facing downwards and flush the compressed air or nitrogen in the broth for 30 seconds.
4.9 Carry out sampling of 0.2µ micron filtered nitrogen.
4.10 Repeat the procedure at any one unfiltered point of use as positive control.
4.11 Carry the sampled media to QC laboratory. Keep all test tubes in incubation.
4.12 Incubate the SCD broth at 20-250C for 72 hrs and further 48 hrs at 30-350C.
4.13 Note down the sampling details in logbook.
4.14 Make entry on media consumption log.
4.15 After completion of incubation record the result in laboratory note book in presence of second person.
4.16 Inspect the positive control sample test tube.
4.17 If there is any visible growth or turbidity observed in sample tube then it is to be considered as positive and identify the microorganism.
4.18 If positive result observed, file OOS and investigate.
4.19 If there is no growth or turbidity observed in sample tube, it shall be considered as compliance with the test
4.20 Discard the test tube after completion of test.

5. Abbreviations
SOP: Standard operating procedure
SCD broth: Soyabean Casein Digest broth
OOS: Out of specification
IPA: Isopropyl alcohol
QC: Quality control
SS: Stainless steel

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