An attempt to replicate a study of the accuracy of test results of medical laboratories was unsuccessful. Limitations of the obtained data prevented the research from having satisfactory internal validity, so no formal report was published. External validity of the study was also limited because the systematic random sample of 78 licensed…

This module, recommended for third or fourth year high school students, consists of three parts. The first part (entitled "Knowing Plastics") gives some background information regarding the origin of plastics, their chemical and physical properties, and the different available types. The second part (entitled "Shaping…

The purposes of water treatment in a marine steam power plant are to prevent damage to boilers, steam-operated equipment, and steam and condensate lives, and to keep all equipment operating at the highest level of efficiency. This laboratory exercise is designed to provide students with experiences in making accurate boiler water tests and to…

The determination of the thickness of a sludge blanket in primary and secondary clarifiers and in gravity thickness is important in making operational control decisions. Knowing the thickness and concentration will allow the operator to determine sludge volume and detention time. Designed for individuals who have completed National Pollutant…

The jar test is used to determine the proper chemical dosage required for good coagulation and flocculation of water. The test is commonly used in potable water, secondary effluent prior to advanced wastewater treatment, secondary clarifier influent, and sludge conditioning practice. Designed for individuals who have completed National Pollutant…

This module describes the process used to determine solids mass and location throughout a waste water treatment plant, explains how these values are used to determine the solids mass balance around single treatment units and the entire system, and presents calculations of solids in pounds and sludge units. The instructor's manual contains a…

Designed for individuals who have completed National Pollutant Discharge Elimination System (NPDES) level 1 laboratory training skills, this module on digestor gas analysis provides waste water treatment plant operators with the basic skills and information needed to: (1) successfully run the carbon dioxide analysis test; (2) accurately record…

A brief overview of the basic concepts and philosophies for sampling water and waste water systems is presented in this module. The module is not intended to specify sampling procedures, frequencies, or locations for specific treatment facilities but rather to outline those general procedures which should be followed when sampling under most…

Designed for individuals who have completed National Pollutant Discharge Elimination System (NPDES) level 1 laboratory training skills, this module provides waste water treatment plant operators with the basic skills and information needed to: (1) standardize a nephelometric turbidimeter; (2) determine the turbidity of a sample; and (3) calculate…

Describes procedures for collecting and using cryptozoic invertebrates in introductory biology classes to develop interest in invertebrate ecology, behavior, physiology, morphology, and taxonomy. (PEB)