SOP for environmental  monitoring of air

by

SOP for environmental  monitoring of air

OBJECTIVE  :To lay down a procedure for environmental  monitoring of air.

SCOPE  :This SOP shall provide the procedure for monitoring the viable air borne count .

RESPONSIBILITY :Microbiologist

ACCOUNTABILITY

Manager QC/QA

PROCEDURE 

  • The microbial environmental conditions  shall be monitored as per defined frequency and sampling schedule  by active air sampling .
  • In case the active air sampler is out of order then settling plate method can be used alternatively for monitoring the microbiological quality of air.
  • PRE START UP:
  • Prepare required quantity of Soyabean Casein Digest Agar media(SCDA)  as per  SOP.
  • Aseptically prepare media plates by adding about 20 to25 ml of the medium into sterile petri plates of 90 x 15 mm size and allow to solidify under LAF.
  • Store  the  prepare  media  plates  in  sterile  stainless  steel  containers  at  a  temperature of  22.5 °C ± 2.5°C.
  • For monitoring carry the stainless steel containers with plates into the area where  plates are to be exposed.
  • Mark the plates appropriately with the date of sampling, location number, and the method used prior to sampling.
  • Active Air Sampling
  • Analyse the  microbial quality of air by sampling 100 litre of air at each of the locations, using Active Air Sampler.
  • Sterilise the stainless steel aspirating head of the air sampler prior to use by autoclaving as per SOP.
  • Carry the preincubated SCDA plates and sterile SS head in a SS container  to the sampling location.
  • At the sampling location remove the lid of the plate and place the plate in the sterile SS head of the air sampler. Assemble the SS head on the main body of the air sampler.
  • Operate the air sampler as per SOP.
  • After the completion of sampling remove the plate from the SS head, cover with the lid and replace the plate in the SS container.
  • Carry the container to the Microbiology laboratory and incubate the media plates at  36°C ± 2°C  for 05 days.
  • After completion of incubation, count the number of colonies on each plate and record the results as number of CFU/m3 using the below given formula:

X = Pr x 1000 / V

Where:

V  = Volume of sampled air

r   = Colony Forming Units counted on 90 mm plates

Pr = Probable count obtained by positive hole correction

X  =  Colony Forming Units per m3 of air

Based on the frequency of air sampling i.e. weekly, monthly, once in two months and once in three months ,record the results.

In case  any of the result  crosses the alert limit, inform  Manager QC/QA ,followed by Manager production

& Engg to take necessary corrective action.

In case any of the result crosses the action limit inform  Manager QC/QA ,followed by Manager production

& Engg, Investigate the probable cause of  higher count  and  sanitize and fumigate the area if  required.