Viroxy's microbiologist about to incubate settle plates

Air Monitoring through Passive Sampling

Passive sampling air monitoring is performed by exposing environment air to agar plates naturally.

Passive air sampling measures microorganism population that are airborne in a facility.


The Method

Passive sampling is performed by exposing agar plates to the environmental air for a certain period. The number of agar plates used depends on the size of the test ground. We usually recommend at least 5 agar plates per room. The microorganism population that settles on the agar plates are analysed.

Passive sampling is cheaper and simpler compared to active sampling which requires a device. Passive sampling also does not produce reliable quantification. We normally recommend clients to select active sampling method instead of passive sampling method as it is more accurate.


Sample Site Selection Criteria

When selecting sites to be sampled, it is important to ask the following questions:

Include sites that are known to harbor high-levels of microorganism.


Colony Findings

Findings are categorised according to this table. The table is based on World Health Organization’s guide on monitoring the environment in vaccine manufacturing facilities.


Service Request Process

  1. To request for this service, submit your enquiry through the contact form and we will contact you. Alternatively, call us at +603 2630 8888 for a discussion.
  2. Please determine the size of the premises you wish to test before discussing with us. 
  3. List potential sites of contamination that may require testing such as door handle, playpen, table etc.
  4. Wait for an e-mail from us which will contain a submission form and quotation. Fill in your details if you agree and send the form back to us.
  5. Wait for a sample acquisition date from us.
  6. Collect settle plates from us and acquire air samples according to the instructions provided. If you'd prefer us acquiring the samples for you, it is possible but appropriate travel fees will be applied.
  7. Send us the settle plates in ice cold condition within 24 hours.
  8. Wait for the result from us. It takes one week to gather the result and another week to generate test report and issue a certificate.

Call us now at +60 (0)3 2630 8888 to speak to one of our experts