Turbidity NTU, Max. No Relaxsation. Desirable Characteristics. Polynuclear aromatic hydro carbons. Radioactive Materials. Method of test. Ref to Cline in IS Other Method of Test. Color , Hazen units, Max. Part II Methylene blue-extraction method. Methods of sampling and test physical and chemical for water used in industry. The criteria shall be satisfied if during a period of time not more than 5 percent of the samples show more than MPN and not more than 20 percent of the samples show more than MPN.
Further the faucal coliforms should not be more than 40 percent of the total coliforms. Methods of sampling and test for industrial effluents, Part II. Methods of sampling and test for industrial effluents, Part III. All incinerators shall meet the following operating and emission standards. Operating Standards. Combustion efficiency CE shall be at least The Combustion efficiency is computed as follows:. Emission Standards. Note :. The autoclave should be dedicated for the purposes of disinfecting and treating bio-medical waste,.
I When operating a gravity flow autoclave, medical waste shall be subjected to :. II When operating a vacuum autoclave, medical waste shall be subjected to a minimum of one pre-vacuum pulse to purge the autoclave of all air. The waste shall be subjected to the following:. III Medical waste shall not be considered properly treated unless the time, temperature and pressure indicators indicate that the required time, temperature and pressure were reached during the autoclave process.
If for any reasons, time temperature or pressure indicator indicates that the required temperature, pressure or residence time was not reached, the entire load of medical waste must be autoclaved again until the proper temperature, pressure and residence time were achieved. IV Recording of operational parameters. Each autoclave shall have graphic or computer recording devices which will automatically and continuously monitor and record dates, time of day, load identification number and operating parameters throughout the entire length of the autoclave cycle.
V Validation test. If you are collecting duplicate samples, label the duplicate bottle with the correct code, which should be determined prior to sampling by the lab supplying the bottles. Use the following procedure for collecting a sample for titration by the Winkler method:.
If you are using a dissolved oxygen meter, be sure that it is calibrated immediately prior to use. Check the cable connection between the probe and the meter. Make sure that the probe is filled with electrolyte solution, that the membrane has no wrinkles, and that there are no bubbles trapped on the face of the membrane.
You can do a field check of the meter's accuracy by calibrating it in saturated air according to th e manufacturer's instructions. Or, you can measure a water sample that is saturated with oxygen, as follows.
Once the meter is turned on, allow 15 minute equilibration before calibrating. After calibration, do not turn the meter off until the sample is analyzed. Once you have verified that the meter is working properly, you are ready to measure the DO levels at the sampling site.
You might need an extension pole this can be as simple as a piece of wood to get the probe to the proper sampling point. Simply secure the probe to the end of the extension pole. A golfer's ball retriever works well because it is collapsible and easy to transport. To use the probe, proceed as follows:. Three types of titration apparatus can be used with the Winkler method: droppers, digital titrators, and burets.
The dropper and digital titrator are suited for field use. The buret is more conveniently used in the lab Fig. For titration with a dropper or syringe, which is relatively simple, follow the manufacturer's instructions.
The following procedure is for using a digital titrator to determine the quantity of dissolved oxygen in a fixed sample:. Some water quality standards are expressed in terms of percent saturation. To calculate percent saturation of the sample:. If you are using the Winkler method and delivering the samples to a lab for titration, double-check to make sure that you have recorded the necessary information for each site on the field data sheet, especially the bottle number and corresponding site nu mber and the times the samples were collected.
Deliver your samples and field data sheets to the lab. If you have already obtained the dissolved oxygen results in the field, send the data sheets to your sampling coordinator. Biochemical oxygen demand, or BOD, measures the amount of oxygen consumed by microorganisms in decomposing organic matter in stream water. BOD also measures the chemical oxidation of inorganic matter i. A test is used to measure the amount of oxygen consumed by these organisms during a specified period of time usually 5 days at 20 C.
The rate of oxygen consumption in a stream is affected by a number of variables: temperature, pH, the presence of certain kinds of microorganisms, and the type of organic and inorganic material in the water.
BOD directly affects the amount of dissolved oxygen in rivers and streams. The greater the BOD, the more rapidly oxygen is depleted in the stream. This means less oxygen is available to higher forms of aquatic life. The consequences of high BOD are the same as those for low dissolved oxygen: aquatic organisms become stressed, suffocate, and die. Sources of BOD include leaves and woody debris; dead plants and animals; animal manure; effluents from pulp and paper mills, wastewater treatment plants, feedlots, and food-processing plants; failing septic systems; and urban stormwater runoff.
BOD is affected by the same factors that affect dissolved oxygen see above. Aeration of stream water by rapids and waterfalls, for example will accelerate the decomposition of organic and inorganic material. Therefore, BOD levels at a sampling site with slower, deeper waters might be higher for a given volume of organic and inorganic material than the levels for a similar site in highly aerated waters.
Chlorine can also affect BOD measurement by inhibiting or killing the microorganisms that decompose the organic and inorganic matter in a sample. If you are sampling in chlorinated waters, such as those below the effluent from a sewage treatment plant, it is necessary to neutralize the chlorine with sodium thiosulfate.
See APHA, BOD measurement requires taking two samples at each site. One is tested immediately for dissolved oxygen, and the second is incubated in the dark at 20 C for 5 days and then tested for the amount of dissolved oxygen remaining. This represents the amount of oxygen consumed by microorganisms to break down the organic matter present in the sample bottle during the incubation period.
Because of the 5-day incubation, the tests should be conducted in a laboratory. Sometimes by the end of the 5-day incubation period the dissolved oxygen level is zero. But it's not at all simple and plain and it is vital for all life on Earth. Where there is water there is life, and where water is scarce, life has to struggle or just "throw in the towel. What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking?
All water is of a certain "quality" and you can't tell by just looking , but what does "water quality" really mean? Water full of dirt and grime might work fine for a tomato plant but would you want to drink it? Water quality can be thought of as a measure of the suitability of water for How much do you know about water properties? Dissolved oxygen DO is a measure of how much oxygen is dissolved in the water - the amount of oxygen available to living aquatic organisms. The amount of dissolved oxygen in a stream or lake can tell us a lot about its water quality.
Nutrients, such as nitrogen and phosphorus, are essential for plant and animal growth and nourishment, but the overabundance of certain nutrients in water can cause a number of adverse health and ecological effects. Nutrients, such as nitrogen and phosphorus, are essential for plant and animal growth and nourishment, but the overabundance of certain nutrients in water can cause several adverse health and ecological effects. Below are multimedia resources related to biological oxygen demand and other related water topics.
The green scum shown in this image is the worst algae bloom Lake Erie has experienced in decades. Phosphorus from farms, sewage, and industry fertilized the. Skip to main content. Search Search. Water Science School. Biological Oxygen Demand.
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