The BioLab is equipped to analyse and test for microbial contamination of water. Various plate count tests are available to estimate bacterial colony forming units (cfu), which is a measure of the total bacterial population in a water sample. Multiple tube dilution technique is used to estimate most probable number (MPN) of total coliforms, some of which would indicate environmental and faecal contamination of water. Confirmatory tests are available to identify indicator organisms associated with environmental and sewage contamination. The bacterial endotoxin assay is available to test the level pyrogens (endotoxins) in water for dialysis.

The plate count methods rely on growth of bacterial colonies on a variety of nutrient mediums incubated at specific temperature for various durations, so that colony becomes visible to the naked eye. But too many colonies, some of which may coalesce with each other would be difficult to count. Hence multiple petridishes with chosen nutrient medium are inoculated with different dilutions of test sample and the colony count is multiplied by the dilution factor.

In the most probable number (MPN) tests, rows of tubes containing lactose broth are inoculated with water samples measuring 10 ml, 1 ml, and 0.1 ml. During incubation, coliform organisms, if present, would produce gas. A small inverted tube (Durham tube) is placed in each test tube to capture as gas is produced by coliform bacteria. Durham tubes float when filled with gas. The number of test tubes in each row, showing definite signs of gas production is identified and a statistical table is used to arrive at the point estimate and range of coliform bacteria in the sample.

The bacterial endotoxin test (BET), based on the fact that the blood of the horseshoe crab (Limulus or Tachypleus) gels or clots when it comes in contact with endotoxin. The Limulus amebocyte lysate (LAL) reagents are used to test for endotoxin using gel-clot method.