What type of drug testing equipment is used?
The test is usually performed on a Hitachi 740 spectrometer at 340 nm wavelength of light. A spectrometer is a piece of scientific equipment that shines a beam of light through the urine sample. The amount of light that passes through the sample is termed “transmittance”, i.e. transmitted through the sample. The light that does not pass through the sample is termed absorbance, i.e., absorbed by the sample. The change in absorbance per minute is the parameter measured to determine if a sample is positive or negative. A baseline is run on each sample to determine the absorbance, because each urine sample is unique and different. Therefore, every sample has a different starting and ending point of the absorbance per minute to determine if a sample is positive or negative.
