1 Subject content and scope of application This standard is the basic principle guidance of sampling technology, and does not include detailed sampling steps. This standard applies to open rivers, closed pipelines, open water bodies, bottom sediments and groundwater sampling.
This standard is a sampling technique guide for quality assurance control, water quality analysis, bottom sediment and sludge, and is designed to obtain reliable data for water pollution identification.
2 water sample type
2.1 General In order to explain the water quality, some parameters of the water are to be determined at the specified time, place or at specific intervals. Concentrations such as inorganics, dissolved minerals or chemicals, dissolved gases, dissolved organics, suspended solids, and bottom deposits.
Certain parameters, such as the concentration of dissolved gases, should be measured on site as much as possible in order to obtain accurate results.
Since chemical and biological samples are collected, processed, and equipment are different, samples should be collected separately.
Sampling techniques are subject to specific conditions, and the classification is described in Chapter 3.
2.2 Instant Water Samples Samples collected from a water body that are not randomly random (in terms of time and location) are called instantaneous water samples.
Instant water samples can be collected manually, either on the surface of the water, at a defined depth or on the bottom. They can also be collected by automated methods.
In general, the sample collected represents only the water quality at the time of sampling and at the sampling point, while automatic sampling is a series of such transient samples based on a predetermined selection time or flow interval.
The following conditions are suitable for instant sampling:
a. When the flow rate is not fixed and the measured parameters are not constant (if a mixed sample is used, the difference between the individual samples may be masked by the mutual reaction);
b. Discontinuously flowing water, such as water discharged in batches;
c. When the water or wastewater characteristics are relatively stable;
d. It is necessary to examine the possible presence of contaminants or to determine when the contaminants are present;
e. When there is a need for high values ​​of pollutants, low values ​​of zui or changes in data;
f. It is necessary to determine the change law of water quality based on the data in a short period of time;
g. When it is necessary to determine the spatial variation of a parameter, such as the variation of a parameter in different sections and/or depths of water or open water;
h. Before developing a larger sampling plan;
i. Determination of certain parameters such as dissolved gases, residual chlorine, soluble sulfides, microorganisms, oils, organics and pH.
2.3 Collecting periodic samples at fixed time intervals (depending on time)
The sample is automatically started and stopped at a specified time interval by a timing device. Samples are typically taken over a fixed period of time and a volume of sample is injected into each container.
When collecting samples by hand, collect periodic samples as described above.
2.4 Collecting periodic samples at fixed emission intervals (depending on volume)
When the water quality parameters change, the sampling method is not affected by the discharge flow rate, and such samples are attributed to the flow ratio sample. For example, the unit volume of liquid flow (for example: 10 000 L), the amount of sample taken is fixed, regardless of time.
2.5 Collect continuous samples at a fixed flow rate (depending on time or time average)
Continuous samples collected at a fixed flow rate can measure all components present during the sampling period, but do not provide a change in the concentration of each parameter during the sampling period.
2.6 Continuous samples collected at AC speed (depending on flow or proportional to flow)
The collection of flow ratio samples represents the overall mass of the water, even if the flow rate and composition are changing, and the flow ratio sample can also reveal these changes that are not observed with the instantaneous sample. Therefore, for flow water with a significant change in flow rate and concentration of the pollutant to be tested, collecting the flow ratio sample is an accurate sampling method.
2.7 Mixed water samples are mixed at the same sampling point in terms of flow rate, time, volume or flow rate, in a known ratio (intermittent or continuous). This sample is called a mixed water sample.
Mixed water samples can be collected automatically or manually.
The mixed water sample is a mixture of several separate samples, which reduces the analysis of the sample, saving time and reducing consumption.
Mixed samples provide an average of the components, so the data for these sample parameters should be verified prior to sample mixing to ensure the accuracy of the sample data after mixing. When the sample is mixed with a significant change in the composition or properties to be tested, the mixed water sample cannot be used, and a single storage method is adopted.
The following conditions are suitable for mixing water samples:
a. When the average concentration needs to be determined;
b. Calculate the mass load per unit time;
c. To assess the impact of special, changing or irregular emissions and production operations.
2.8 Integrated water samples For a certain purpose, the instantaneous water samples taken from different sampling points are mixed into one sample (the time should be as close as possible to obtain the required data). This mixed sample is called a comprehensive water sample.
The following conditions are suitable for integrated water samples:
a. In order to evaluate the average component or total load, such as a river or river, the composition of the water varies along the width and depth of the river, and is proportional to the point on the entire cross-section and their relative flow. Mixed sample
b. When several wastewater channels enter the integrated treatment plant respectively.
Because several wastewaters react with each other, they may have a significant effect on the treatability and its components. Integrated water samples can provide more useful information when mathematical predictions of their interactions may be incorrect or impossible.
Natural and artificial lakes or rivers often show changes in spatial distribution. In most cases, changes in total or average values ​​are not particularly pronounced, and local changes are more important. In this case, it is more effective to test the single sample than to test the integrated water sample.
3 sampling type
3.1 Sampling of open rivers When monitoring the sampling of open river water, the following basic points should be included:
a. sampling of water use locations;
b. After the sewage has flowed into the river, it should be sampled at a well-mixed location and at the location before the inflow;
c. Sampling of well-mixed locations and mainstream and tributary locations prior to mixing after tributary convection;
d. sampling of the location after the mainstream diversion;
e. Sampling locations set according to other needs.
Each sampling point in principle provides for the collection of fixed-point samples at different depths across different locations of the river.
When sampling, it is generally selected to be continuous sunny days before sampling, and the water quality is stable (except for special needs).
The sampling time is determined on the basis of people's activities, the working hours of the factory and the time when the pollutants flow. In addition, in the tidal zone, the situation of the water quality should be considered to include the bad time of the water quality in the sampling time.
3.2 Sampling of closed pipes Sampling in closed pipes will also encounter similar problems with sampling in open rivers. The sampler probe or sampling tube should be placed properly downstream of the inlet water and the sampling tube must not be close to the tube wall. Turbulence parts, such as in the "T" shaped tube, elbows, and the rear of the valve, can be fully mixed, generally as a good sampling point for Zui, except for isokinetic sampling (ie, constant velocity sampling).
3.3 Sampling of open water bodies in open water bodies may cause large differences in water quality due to different locations and stratification of temperature.
When investigating water quality conditions, it should be considered that the water quality in the layering and circulation periods is significantly different. To understand the water quality during the cycle period, surface water samples can be collected; to understand the water quality during the layering period, the samples should be sampled according to depth.
When investigating the pollution status of waters, it is necessary to conduct comprehensive analysis and judgment, and grasp the basic points (such as the location before the inflow of wastewater, the place where the infusion is fully mixed, the location of the water, the location of the outflow, etc., some of which can refer to the sampling of the open river, but it cannot be equated. ) to obtain a representative water sample.
When sampling, it is generally selected to be continuous sunny days before sampling, and the water quality is stable (except for special needs).
3.4 Bottom sediment sampling sediments may be collected using a grab, mud collector or drilling device.
Typical deposition processes typically have large differences in delamination or composition. In addition, the unevenness of the river bed and the local movement of the river can cause large changes in the thickness of each sediment layer.
In addition to the main pollution source and the estuary site, the location of the mud collection site should be selected due to the accumulation of topography and tidal conditions and the deterioration of the sediment. Alternatively, you can choose a location where the deposited layer is thin.
In the case where the distribution of sediment accumulation is unknown, the location of the sediment should be balanced. In the estuary part, due to the easy change of sediment accumulation, it is necessary to add sampling points appropriately. The method of mud mining, the principle is to change the position slightly in the same place for collection.
Mixed samples can be collected by a mud collector or a grab. When it is necessary to understand the stratification, a drilling device can be used.
When collecting sediment, whether it is a core or a representative mixed sample of defined depth deposits, the nature of the sample must be known in order to properly interpret these analyses or tests. In addition, if the degree of change in the bottom sediment and its nature are difficult to predict or impossible to know, sampling points should be added as appropriate.
Collecting individual samples not only results in changes in sediments, but also component distribution maps, so individual samples are more useful than data from mixed samples.
The sample containers provided in Chapter 5 are also suitable for the storage of sediment samples, generally using wide-mouth containers. Since this sample contains a lot of water, pay special attention to the seal of the container.
3.5 Groundwater sampling Groundwater can be divided into upper layer stagnant water, diving and confined water.
The water quality of the upper layer of stagnant water is basically the same as that of surface water.
The aquifer is directly connected to the atmosphere and water through the vadose zone, so it has seasonal characteristics.
The geological conditions of confined water are different from those of diving. It is directly affected by hydrological and meteorological factors, and the thickness of the aquifer is not subject to seasonal changes. The water quality is not easily polluted by human activities. Some factors that should generally be considered when collecting samples:
a. The groundwater flow is slow and the rate of change of water quality parameters is small;
b. The temperature change below the surface is small, so when the sample is taken out of the earth's surface, its temperature changes significantly. This change can change the chemical reaction speed, reverse the exchange direction of the anion and cation in the soil, and change the growth rate of the microorganism;
c. Some compounds also oxidize due to absorption of carbon dioxide and changes in pH due to changes in alkalinity;
d. Some gases dissolved in water, such as hydrogen sulfide, are highly volatile when the sample is taken out of the surface;
e. Organic samples may be affected by certain factors, such as absorption of sampler materials, contamination, and loss of volatile materials;
f. Soil and groundwater may be severely contaminated, affecting the health and safety of the sampling staff.
A water sample taken from a monitoring well can only represent a horizontal or vertical local condition of an aquifer, and cannot be sampled at any point in the water system as it is for surface water. Because it is very difficult to do so, it costs a lot of money.
If the purpose of the sampling is simply to determine if there is any contaminant in a particular source, then simply collect the water sample from the water pipe. When the purpose of sampling is to determine the horizontal and vertical distribution of certain organic pollutants or some pollutants, and make corresponding evaluations, then it is necessary to organize considerable human and material resources for research.
For regional or large-area monitoring, existing wells, fruit or tributaries of rivers can be used, but they must meet the monitoring requirements. If time is tight, only some representative sampling points should be selected. However, if the source of pollution is small, such as landfill waste, lagoons, or low concentrations of pollutants, such as organic matter, it is necessary to set up a special monitoring well. The number and location of these additional wells depend on the purpose of the monitoring, the characteristics of the aquifer, and the migration of contaminants within the aquifer.
If the potential source of contamination is above the groundwater level, it is necessary to sample in the aerated zone to get a real picture of the threat to groundwater. In addition to chlorides, nitrates and sulfates, most of the contaminants are adsorbed on the gas-filled material and migrate under appropriate conditions. Therefore, it is very possible to collect groundwater samples that have been in existence for many years, and no new pollution is observed. This will give people the illusion of safety. In fact, pollutants are always passing through the gas at a very slow rate. Groundwater migration. It is also important to understand the geological data and geological conditions of the hydrology and the background of the groundwater.
In addition, the collection of water samples should also take into account that the composition of the water close to the well wall can hardly represent the entire groundwater quality of the sampling area, as there may be drilling contamination near the well and certain important environmental conditions, such as redox potential. There is a big difference between the near well and the surrounding groundwater carrying material. Therefore, it is necessary to extract an appropriate amount before sampling.
3.6 Precipitation sampling It is very difficult to accurately collect precipitation samples. Before the precipitation, the sampler must be covered and opened only after the precipitation actually appears. Take the whole process water sample for each precipitation (precipitation starts to end). When collecting samples, avoid sources of pollution, and there should be no tall trees or buildings that block rain or snow in order to obtain accurate results.
4 sampling equipment
4.1 Sampling equipment for the determination of physical or chemical properties
4.1.1 Instantaneous non-automatic sampling equipment
4.1.1.1 Overview Instant Samples When collecting surface samples, use a bucket or a jar to sink into the water. After filling the water, raise the water surface.
For fixed-point sampling of selected depths of stratified water, it is recommended to follow the method described in 4.1.1.3. If you only need to know the average water quality of a vertical section of a water body, you can sample it according to the comprehensive depth method described in 4.1.1.2.
4.1.1.2 Integrated depth sampling equipment Comprehensive depth sampling requires a set of mechanical devices to clamp the bottle and sink it into the water. The sampling bottle with the heavy object sinks into the water at a uniform speed, and the water samples of the entire vertical section are introduced into the sampling bottle through the injection hole.
In order to be able to aliquot the water sample at all depths, the speed at which the sample bottle settles or rises should vary with depth, or the sample bottle can have an adjustable orifice to maintain the change in water pressure. The water injection flow rate is constant.
When there is no such sampling device, an empty sampler can be used to separately collect samples of each depth and then mix.
The empty sampler is a manual, easy-to-use sampler. The sampler is a glass or plastic cylinder with open ends, a scale on the side, a thermometer, a hose on the lower side, and a device for weighting the bottom. The top and bottom ends have two semicircular covers that open in the same direction. When the sampler sinks into the water, the two semicircular covers on both ends are opened upwards, and the water does not stay in the sampler, reaching the predetermined depth. The semi-circular lids at both ends are covered, that is, the sample of the desired depth is taken. (The above-mentioned emptied sampler is just one of them. Others can be used as long as they can achieve the same effect.)
4.1.1.3 The selected depth sampling device will plug the sample bottle with heavy objects and sink into the water. When the sample bottle sinks to the selected depth, the bottle is opened and the bottle is filled with water and then plugged. This method does not apply to samples with special requirements (eg dissolved oxygen).
For special requirements, reversed water collectors, vented water collectors, etc. can be used.
Samples of stratified water are collected, and the venting type water collector described in 4.1.1.2 may also be used to obtain a sample of a vertical section.
4.1.1.4 Grab-type dredgers that collect sediments Grapples-type muds designed with their own weight or leverage are designed to have different characteristics, including spring braking, gravity or toothed plate locking methods. These vary with the depth of the mud layer and vary with the size and area of ​​the sample taken. Therefore, the nature of the sample taken is affected by the following factors:
a. the depth through the mud layer;
b. the angle at which the tooth plate is locked;
c. Locking efficiency (the ability to avoid obstacles in objects);
d. causing disturbances and causing loss of sample or sanding off sample components or organisms at the mud-water interface;
e. Stability of the sample in the rapids.
When selecting a dredger, consideration should be given to habitats, water flow conditions, sampling areas, and available vessel equipment.
4.1.1.5 Grab Bucket Grab bucket is very similar to ground bucket equipment. They are settled to a selected sampling point by a boom operation to collect a larger amount of mixed sample, which is more representative of the selected sampling location than the use of a dredger.
4.1.1.6 Core sampler The core sampler collects sediment vertical profile samples. The collected core samples do not have mechanical strength. Care should be taken to maintain the longitudinal integrity of the mud samples when removing the sample from the sampler to obtain samples of each layer.
4.1.2 Automatic sampling equipment
4.1.2.1 Non-proportional automatic sampler
a. Non-proportional isochronous discontinuous autosampler automatically collects the quantitative water samples from the designated sampling points into the sample storage containers of the sampler according to the set sampling time interval and the storage sequence.
b. The non-proportional isochronous continuous autosampler automatically collects the quantitative water samples from the designated sampling points into the respective sample containers of the sampler according to the set sampling time interval and the storage sequence.
c. The non-proportional continuous automatic sampler automatically collects the quantitative water sample from the specified sampling point into the sample container of the sampler.
d. Non-proportional isochronous mixing The automatic sampler automatically collects the quantitative water sample from the specified sampling point into the sample storage container of the sampler at the set sampling interval.
e. Non-proportional isochronous mixing automatic sampler automatically collects the quantitative water samples from the specified sampling points to the mixed storage of the sampler according to the set sampling time interval and the storage sequence, and according to the set number of samples. In the sample container.
Such a sampler should have the function of collecting 2 to 10 mixed samples in a single sample container.
4.1.2.2 Proportional automatic sampler
a. Proportional isochronous mixing The automatic sampler automatically collects a proportional water sample with a proportional flow rate from the specified sampling point to the mixed sample container in the sampler at a set sampling interval.
b. When the ratio is not equal, the hybrid automatic sampler automatically collects the quantitative water sample from the specified sampling point into the mixed sample container in the sampler for each set volume of sewage.
c. Proportional isochronous automatic sampler
According to the set sampling time interval, it is proportional to the sewage discharge flow rate, and the water samples are continuously collected from the designated sampling points into the respective storage sample containers in the sampler.
d. Proportional isochronous autosampler
According to the set sampling time interval and the storage sequence, the quantitative water samples proportional to the sewage flow rate are automatically collected from the designated sampling points into the respective sample containers in the sampler.
e. Proportional isochronous mixing automatic sampler automatically collects the quantitative water sample proportional to the sewage flow from the specified sampling point to the sampler according to the set sampling time interval and the storage sequence, and according to the set number of samples. In each of the mixed sample containers.
4.2 Equipment for collecting biological characteristics samples
4.2.1 General Some bioassays, like the sampling of physical and chemical analysis, can be done on site. However, most samples must be returned to the laboratory for testing. Some sampling equipment can be performed manually (via divers) or automated telemetry observations. And collecting certain biological species or biological groups.
The sampling range described in this section is primarily concerned with simple equipment that is routinely used.
For the collection of biological samples, the ideal is a jar. The bottle diameter of the Guangri bottle is close to the diameter of the wide-mouth bottle. The bottle is made of plastic or glass.
4.2.2 Plankton
4.2.2.1 Phytoplankton sampling techniques and equipment are similar to those described in transient and fixed-point samples for the detection of chemical in water. In most lake surveys, use bottles or plastic drums with a volume of 1 to 3 L and collect them using the sampling device in 4.1.1.3. Quantitative detection of phytoplankton should not be collected using netting.
4.2.2.2 Zooplankton Collection of zooplankton requires a large number of samples (up to 10L). When collecting zooplankton samples, using a cable to manipulate the water sample (see 4.1.1.3), it is also possible to use a nylon mesh for measuring plankton. The size of the grid used depends on the species of zooplankton tested.
4.2.3 benthic organisms
4.2.3.1 Aquatic attached organisms For the quantitative collection of aquatic adherent organisms, a standard microscope slide (diameter 25 mm x 75 mm) is suitable. In order to accommodate two different aquatic conditions, the slide requires two forms of base brackets.
In small, shallow rivers, or along lakes, the water is relatively clear, and the slides are mounted on shelves or placed on a shelf fixed to the bottom. In the middle of a large river or lake, the water is relatively turbid, and the slide can be fixed on a frame made of polypropylene plastic. The upper end of the shelf is connected with a polystyrene foam block to make it float in the water.
Slides are exposed to water for a certain period of time. (Depending on the water quality, the time is usually about two weeks in the water.)
Note: The exposure time of the slide in water is not fixed and should be determined depending on the attachment. If the water quality is turbid, the exposure time is the same, and too many attached organisms affect the microscopic examination.
4.2.3.2 Large-scale aquatic plants For qualitative sampling, the sampling equipment varies with the depth of the water according to the specific conditions. In shallow water, garden cookware can be used. For deeper water, mud collector can be used. Currently, it has been used in diving exploration. Start using the matching underwater breathing apparatus (SCUBA for short).
Quantitative sampling, in addition to determining that the sampling area has been determined, or that large aquatic plants have been measured, or otherwise evaluated, can be similar to the above techniques.
4.2.3.3 The sampling equipment currently used by large invertebrates does not provide quantitative data for all habitat types. Usually limited to sampling within a specified water area. In some cases, laboratory personnel are required to rely primarily on qualitative sampling, and analysis of these samples requires extensive replicates and time.
In the control survey of benthic organisms, the effects of natural habitat differences between different sampling points must be carefully recorded. However, since the sampling technique and the applicable equipment are very different, there is relatively no restriction on the type of habitat to be investigated. The form of sampler used depends on many parameters - the depth of the water, the flow, the physical and chemical properties of the substrate, and so on.
The equipment used to collect large invertebrates is:
a. Grab and mud collector;
b. handle net;
c. cylinder and box sampler;
d. Drilling equipment (for sediment sampling);
e. Pneumatic pump;
f. artificial substrate;
g. drift nets (drift nets).
4.2.4 Fish-trapped fish are either active or inactive. Sampling methods for activities include the use of pull nets, trawling, electronic fishing, chemicals, and hooks and hooks. Inactive sampling methods include trapping methods (such as gill nets, fine nets) and trapping methods (such as traps, traps, etc.). The use of sampling equipment for the migration of fish and the “rapid replenishment†of fish (ie the rapid growth of fish stocks) has certain limitations on the qualitative and quantitative testing of fish.
4.3 Equipment for collecting microorganisms Sterilized glass bottles or plastic bottles are suitable for collecting most samples. Deep water sampling devices (Article 4.1.1.3) can be used when sampling deeper locations below the surface of lakes and reservoirs.
All instruments used, including pumps and their associated equipment, must be completely free of contamination and the equipment itself must not introduce new microorganisms. Sampling equipment and containers should not be rinsed with water.
4.4 Equipment for collecting radioactive property samples Sampling techniques and equipment for collecting chemical components of water and wastewater are generally applicable to radioactivity determination.
Hard glass and polyethylene plastic bottles for general physical and chemical analysis are suitable for radionuclide analysis. However, it is necessary to select a suitable sampling container for the form of the test nuclide (for example, measuring total alpha, total beta radioactivity can be used in polyethylene bottles, and measuring sputum, only glass containers can be used). The sample vials should be washed and dried before sampling.
When collecting water samples, try to prevent the radionuclide from being adsorbed on the surface of the container and lost (for example, soaking the stable isotope of the nuclide to be tested for more than one day).
5 Sample Containers and Auxiliary Equipment The following information is provided to aid in the selection of sampling vessels during general sampling.
5.1 Materials In order to evaluate water quality, the chemical components of the water (test substances) need to be analyzed, and the concentration ranges from trace amounts to trace amounts to large amounts. In addition, interaction between components, photolysis, etc., should shorten storage time and restrictions on light and heat exposure. Biological activity should also be considered. What zui often encounters is improper cleaning of the container, and contamination of the sample by the material of the container itself and adsorption on the wall of the container.
When selecting a container for collecting and storing samples, there are other factors, such as drastic changes in temperature, crack resistance, sealing properties, repeated opening conditions, volume, shape, quality supply, price, cleaning and reuse. Sex and so on.
Most of the inorganic samples are made of polyethylene, fluoroplastic and carbonate. Commonly used high density polyethylene, suitable for analysis of sodium silica, total alkalinity, chloride, specific conductivity, pH and hardness in water. A brown glass bottle can be used for the photosensitive material. Stainless steel can be used for high temperature or high pressure samples or for samples of trace organics.
General glass bottles are used for organic and biological species. Plastic containers are suitable for radionuclides and water samples containing elements belonging to the main components of glass. Sampling equipment often uses neoprene gaskets and oil-lubricated valves, which are not suitable for collecting organic and microbial samples.
Therefore, in addition to the physical characteristics required above, the selection of containers for collecting and storing samples, especially for the analysis of trace components, should follow the following guidelines:
a. The material used to make the container should reduce the pollution of the water sample to a small size, such as glass (especially soft glass), the dissolution of inorganic components and the dissolution of organic compounds and metals from plastics and synthetic rubber (plasticized vinyl cap liner, chlorine Butadiene rubber cover);
b. cleaning and treating the properties of the container wall in order to reduce the contamination of the surface of the container by trace components such as heavy metals or radionuclides;
c. The material used to make the container is chemically and biologically useful, reducing the reaction between the sample component and the container to a low degree;
d. Errors may also be caused by the adsorption of the analyte on the sample container. Especially for the measurement of trace metals, other analytes (such as detergents, pesticides, phosphates) can also cause errors.
5.2 Automatic sampling line and storage sample container sampling line refers to the pipeline through which the sample is sucked from the sampling point to the storage sample container by automatic sampling. The time the sample stays in the sample line should be based on the time the sample is stored in the container. The material of the sampling line and the material of the storage container can be selected according to the criteria described in Section 5.1.
5.3 Types of sample containers
5.3.1 General Determination of physical and chemical parameters of natural water, using polyethylene and borosilicate glass for routine sampling. In addition, Zui uses chemically inert materials and is too expensive for routine use. Commonly used are various types of fine mouth, wide mouth and bottle with screw cap, cork stopper (external chemically inert metal foil), rubber stopper (not ideal for the study of organic matter and microorganisms) and grinding Glass stopper (alkaline solution is easy to stick to the plug). These bottles are easy to obtain and inexpensive. If the sample is placed in a box and sent to the laboratory for analysis, the lid must be designed to prevent loosening of the stopper and to prevent spillage or contamination of the sample.
5.3.2 Containers for special samples In addition to the above-mentioned matters to be considered, some photosensitive substances, including algae, are used to prevent light from opaque or colored glass containers, and they should be placed during storage. Light place. The sample collected and analyzed contains dissolved gases, which change the composition of the sample by aeration. The fine-mouth biochemical oxygen demand (BOD) bottle has a radial-shaped glass stopper, which reduces the absorption of air to a low degree. Special sealing measures are required during transportation.
5.3.3 Trace organic pollutant sample containers In general, the sample vials used are glass bottles. All plastic containers interfere with high sensitivity analysis, and glass or Teflon bottles should be used for this type of analysis.
5.3.4 Containers for the inspection of microbial samples The basic requirement for the use of microbial sample containers is the ability to withstand high temperature sterilization. In the case of freeze sterilization, the materials of the bottles and liners should also comply with this Code. The material should not produce and release chemicals that inhibit microbial viability or promote reproduction during sterilization and sample storage. Samples should be sealed and packaged in the mouth of the container before opening to prevent contamination.
5.4 Sample transport Empty sample containers are transported to the sampling site, and the samples are loaded and analyzed in the laboratory. The box can be made from a variety of materials - such as foam, corrugated cardboard, etc. - to reduce the loss of samples during transport to a low limit. The lid of the box is typically lined with a barrier material to apply a slight pressure to the stopper. When the temperature is high, prevent the biological sample from changing, and the sample should be stored in cold storage or preserved with ice.
5.5 Quality Control To prevent contamination of the sample, each laboratory should implement an effective container quality control program as in the general quality assurance program. Randomly select the cleaned bottle and inject high-purity water for analysis to ensure that the sample bottle does not leave impurities. As for the quality assurance in the sampling and storage procedures, it should also be analyzed by adding the same reagents as the sample after sampling.
6 signs and records
6.1 Overview After the sample is injected into the sample vial, it is carried out in accordance with the national standard “Technical Regulations for the Preservation and Management of Water-Sampling Samplesâ€. On-site records are very useful in water quality survey programs, but they can easily be misplaced or lost; never rely on them to replace detailed information. The details should accompany the sample from the sampling point until the end of the analytical tabulation process.
The minimum amount of information required for Zui depends on the end use of the data.
6.2 At least the following information should be provided for surface water:
a. measurement project;
b. name of the water body;
c. the location of the location;
d. sampling point;
e. sampling method;
f. water level or water flow;
g. meteorological conditions;
h. temperature, water temperature;
i. method of pretreatment;
j. The appearance of the sample (suspended matter, sedimentation, color, etc.);
k. Whether there is odor;
l. sampling year, month, day, sampling time;
m. Sampler's name.
6.3 At least the following information should be provided for groundwater:
a. measurement project;
b. location location;
c. sampling depth;
d. the diameter of the well;
e. pretreatment method;
f. sampling method;
g. the structure of the aquifer;
h. water level;
i. The amount of water produced by the water source;
j. The main use of water;
k. meteorological conditions;
l. Appearance when sampling;
m. water temperature;
n. sampling year, month, day, sampling time;
o. The name of the sampler.
6.4 Supplementary information Whether to store or add stabilizers should be recorded.
Appendix A Required Performance of Automatic Sampling Equipment (Reference)
The following items serve as a guide for designing, selecting automated sampling equipment or sampling components. Users should focus on those performances when developing a specific sampling technique.
A1 Strict structure and functional components of Zui (especially electronic parts).
A2 parts exposed or immersed in water should be reduced to a small number of zui.
A3 Corrosion resistance.
The A4 is relatively simple in design and easy to maintain and operate.
A5 Whether the cleaning of the container on the automatic sampling supply line can meet the requirements (refer to the container material). The ability of the container to accept on the automatic sampling supply line.
A6 Possibility of being blocked by solids.
A7 Output volume accuracy.
A8 Analytical data provides a good correlation compared to manually obtained samples.
The A9 sample container is easy to disassemble, clean and reassemble.
The A10 portable sampler should be fully enclosed, lightweight, readily available and resistant to harsh weather conditions and capable of operating over a wide range of environmental conditions.
A11 is capable of sampling a flow ratio sample or a time mixed sample.
A12 can adjust the flow rate of the inhaled liquid and, if necessary, prevent phase separation.
A13 The suction tube has a small internal diameter of 12 mm and is equipped with a streamlined filter to prevent clogging and solids accumulation.
A14 Ability to assign duplicate aliquots to each bottle.
A15 For on-site sampling - performance of AC and DC power operation, DC power should be maintained for 120h to provide 1h sample volume. If explosion-proof is required, pneumatic sample and control components must be used.
A16 For temperature- and time-sensitive samples, the sample can be stored at 4 to 6 °C for 24 h at ambient temperatures up to 40 °C.
A17 When collecting samples separately, the small sample volume of the batch sample is 0.5L.
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