Illinois Administrative Code › Title 77 - PUBLIC HEALTH › Part 465 - CERTIFICATION AND OPERATION OF ENVIRONMENTAL LABORATORIES › Subpart B - MICROBIOLOGICAL ANALYSES OF PUBLIC WATER SUPPLY SAMPLES › Section 465.390 - General Quality Assurance Procedures

Current through Register Vol. 48, No. 28, July 12, 2024
a) A written description of the current
				laboratory quality control and quality assurance program shall be maintained
				and made available to analysts in an area of the laboratory where analytical
				work takes place. The quality assurance plan shall address all of the items
				listed in the Manual for the Certification of Laboratories Analyzing Drinking
				Water. The quality assurance plan shall be reviewed annually and updated as
				necessary. A record of analytical quality control tests and quality control
				checks on media, materials, and equipment shall be prepared and retained for
				five years.
b) Standard operating
				procedures for each parameter for which the laboratory is certified and for all
				required quality control procedures shall be maintained and made available to
				analysts in an area of the laboratory where analytical work takes
				place.
c) The following minimum
				requirements shall apply to analytical quality control tests for general
				laboratory practices and methodology:
1) Each
				laboratory shall successfully analyze at least one set of proficiency testing
				(PT) samples once every 12 months, for each method (For example, Colilert (18
				hour) and Colilert (24 hour) would require a PT for each assay.) for which it
				is certified. When PT sample results indicate technical error, the Department
				will provide appropriate technical assistance to determine the cause and make
				suggestions for correction of the problem.
2) Each analyst approved for the total
				coliform count procedure by the membrane filter technique for source water
				samples (SWTR) shall verify monthly 10 colonies, including each type of
				atypical colony observed. Counts shall be adjusted based on percent
				verification.
3) Each analyst
				approved for the fecal coliform procedure by the membrane filter technique for
				source water samples (SWTR) shall verify a positive water sample monthly. At
				least 10 isolated colonies shall be chosen from membranes containing typical
				blue colonies and, if present, atypical colonies of different morphological
				types and shall be transferred to lauryl tryptose broth. Positive tubes shall
				be transferred to EC medium. The lauryl tryptose broth shall be incubated at
				35.0 °
										± 0.5 ° C for 24 to 48 hours. The EC medium shall be
				incubated at 44.5 °
										± 0.2 ° C for 24 hours + 2 hours. Turbid
				growth with gas production indicates a positive result. Counts shall be
				adjusted based on percent verification.
4) If there is more than one analyst in the
				laboratory, at least once each month each analyst shall count the same
				heterotrophic plate count plate, total coliform membrane, and fecal coliform
				membrane (per certified method used to test source water samples under the
				SWTR). Colony counts between analysts shall agree within 10 percent. This
				requirement does not apply to SimPlate.
5) The standards for laboratory pure water
				specified in Section
				465.380
				shall be met.