Properly cleaned labware, whether made of glass, plastic or metal and sterilized when appropriate, is essential for microbiological testing. Proper washing ensures that all traces of compounds from previous analyses are removed. Failure to properly wash labware could introduce toxic or nutritive compounds into the analytical testing, which could skew laboratory results.
Cleanse labware and sterilize, when appropriate, before first use. Store all clean items in a dust-free environment protected to maintain its cleanliness. Sterilized glassware must be covered to maintain sterility. After each use all microbiologically contaminated labware must be disinfected or sterilized before cleaning to reduce exposure of laboratory personnel and the work environment to contaminants during cleaning. If there is a possibility of dried material on labware after use, before autoclaving place the used items into an autoclavable container with sufficient water and detergent to cover the used labware. If this is not possible or suitable in the available work area and material has dried on labware, presoak the labware or use a stronger laboratory-grade detergent.