6P.9—Apparatus, materials and safe technique

Choose apparatus that measures the needed variable with suitable resolution, calibrate it, check for leaks or zero error, and use appropriate biological containment and waste disposal.

A colorimeter needs a blank and clean cuvette; a respirometer needs a sealed system and temperature control; a microbial plate needs aseptic handling and safe incubation.

More decimal places do not create more accuracy, and sterile technique does not remove all biological risk.