GB/T 5748-1985 Method for determination of dust in the air of workplaces
Some standard content:
National Standard of the People's Republic of China
Methods for airborne dust
measurement in workplace
UDC 613.. 638
GB 5748--85
This standard is formulated to evaluate the degree of hazard of dust in the air of the workplace, strengthen the scientific management of dust prevention measures, protect the safety and health of employees, and promote production development. This standard is applicable to the determination of dust concentration, free ammonia content and dust concentration in the air of the workplace. 1 Terminology
1.1 Workplace
The place where workers often or regularly stay during the production process. 1.2 Dust
Solid particles suspended in the air of the workplace. 1.3 Dust concentration
The mass (mg/m*) or number (particles/cm) of dust contained in a unit volume of dense air. This method adopts mass concentration. 1.4 Free silicon oxide
refers to crystalline silicon dioxide.
1.5 Dust dispersion
The distribution ratio of the number or mass of dust in each particle size range. This method uses the number of horizontal distribution points. 1.6 Dust measurement points
The locations that must be monitored in the workplace contaminated by dust. 2 Principles for the selection of dust measurement points
2.1 The dust measurement points should be set at representative locations where workers are exposed to dust. 2.2 The dust measurement location should be selected within the range of frequent activities of dust-exposed personnel and in the breathing zone where the dust is more evenly distributed. When there is wind flow, "- generally it should be selected on the downwind side or return air side of the work site. The sampling location of the mobile dust-generating point should be located at a representative location in the production activities, or the sampler should be set up on a mobile device. 3 Dust concentration determination method
3.1 Principle Extract a certain volume of dust-laden air and retain the dust on a filter membrane of known mass. The increment of the filter membrane after the sample is taken is used to calculate the mass of dust per unit volume of air (cut g/m3) 3.2 Equipment
8.2.1 The sampler uses a dust sampler that has passed the product inspection. When sampling in a workplace that requires explosion-proof, use an explosion-proof dust sampler. The airtightness of the sampling head It shall meet the requirements of Appendix A. 9.2.2 The filter membrane shall be a perchloroethylene fiber filter membrane. When the dust concentration is lower than 50 mg/m*, a filter membrane with a diameter of 40 mm shall be used. When it is higher than 50 mg/m*, a filter membrane with a diameter of 75 mm shall be used. When the perchloroethylene fiber filter membrane is not applicable, a corrugated glass red vitrine membrane shall be used instead. 3.2.3 Gas flow meters commonly use rotary flow meters with a flow rate of 15 to 40 l/min. Turbine gas flow meters can also be used. When the flow rate needs to be increased, the above flow meter can be increased to 80 l/min. At least each half of the flow meter shall use a bell-type gas meter, a soap film flow meter or a gas flow meter with an accuracy of ±1%. Ministry of Health of the People's Republic of China
1986 01-27
Ministry of Labor and Personnel of the People's Republic of China
1986-05-01Implementation
GB 5748-85
The flow monitor should be calibrated times. When the flow meter is obviously contaminated, it should be cleaned and calibrated in time. 3.2.4 Use an analytical instrument with a sensitivity of not less than 0.0001g every day. According to the regulations of the metrology department, calibration should be performed times every day. 3.2.5 Stopwatch or a timer equivalent to a stopwatch. 3.2.6 The desiccator contains color-changing rubber chips.
3.3 Determination procedure
3.3.1 Preparation of filter membrane Use tweezers to remove the backing paper on both sides of the filter membrane, place it on a balance to weigh it, and record the initial mass. Then install the filter membrane into the filter membrane clamp. After confirming that the filter membrane has no wrinkles or cracks, put it in a numbered sample box for use. 3.3.2 Installation of the sampler Take out the prepared filter membrane clamp, install it into the sampling head and tighten it. When sampling, the dust-receiving side of the filter membrane should face the dust-laden airflow. When facing the dust-laden airflow, splashing mud and sand cannot be avoided. When the sample is contaminated, the dust receiving surface can be sideways. 3.3.3 The time of sampling start For continuous dust-generating work points, it should be 30 minutes after the start of the work. For intermittent dust-generating work points, the workers should be placed on the sampling:
3.3.4 The sampling flow rate is usually 15-401/min. When the concentration is low, the flow rate can be increased appropriately, but it must not exceed 801/min. During the entire sampling process, the flow rate should be stable. $.3.5 The duration of sampling is determined according to the estimated value of the dust concentration at the dust measuring point and the minimum value of the required dust increase on the filter membrane, but generally it shall not be less than 10min (when the dust concentration is higher than 10mg/m*, the gas sampling volume shall not be less than 0.2m3, and when it is lower than 2mg/m, the gas sampling shall be 0.5~1m\). The duration of sampling is generally estimated according to formula (1): Am ×1000
Wu: t-sampling duration, min;
- required minimum dust increment, the mass should be greater than or equal to 1mg;
- estimated dust concentration in the workplace, mg/kg; (1
Q- flow rate during sampling, 1/min.
3.3.6 The increment of dust collected on the filter membrane The increment of dust on the filter membrane with a diameter of 40mm should not be less than 1mg, but not more than 10mg. The filter membrane with a diameter of 75mm should be made into a cone for sampling, and its dust increment is not subject to this limit. 3.3.7 Treatment of samples after sampling After sampling, remove the filter membrane from the filter membrane holder. In general, it does not need to be dried and can be directly placed on the day specified in 3.2.4. Weigh and record the mass. If the relative humidity on site is above 90% or there is water mist during sampling, the filter membrane should be placed in a desiccator for 2h and weighed, and the measurement results should be recorded. After weighing, put it in the desiccator for 30 minutes and weigh it again. When the difference between the two adjacent mass measurements does not exceed 0.1 m3, take the minimum value. 3.4 The dust concentration is calculated according to formula (2):
C- mom.10..
-dust concentration, mg/m3,
Where: C—
filter membrane mass before sampling, Ⅱg;
filter membrane mass after sampling, mg:
sampling time i, min
Q——sampling flow rate, I/ min.
(2)
3.5 This method is the basic method. If other instruments or methods are used to determine the dust mass concentration, this method must be used as the basis. 4 Method for determining the content of free silicon dioxide in dust 4.1 Chen Li
Silicates are soluble in heated pyrophosphoric acid, while quartz is almost insoluble. The content of free silicon dioxide in dust is determined by mass method. 4.2 Equipment
4.2.1 Conical flask (50ml),
4.2.2 Shotgun (25ml).
4.2.3 Beaker (200～400ml)
4.2.4 Glass funnel and funnel stand.
4.2.5 Thermometer (0～360℃).
4.2.6 Electric furnace (adjustable).
High temperature electric furnace (with temperature controller).
GB 5748—85
Porcelain crucible or platinum crucible (25ml, with cover). Snail forceps or platinum-tipped snail forceps.
Desiccator (containing color-changing silica gel).
Analytical balance (sensitivity is 0.0001g).
Agate mortar.
Fixed fish filter paper (slow speed)
4.2.14 pH test paper.
4.3 Reagents
4.3.1 Pyrophosphoric acid (heat 85% phosphoric acid to boiling, until no bubbles appear at 250℃, cool, and store some in a reagent bottle). 4.3.2 Hydrofluoric acid.
4.3.3 Crystalline ammonium nitrate.
4.3.4 Hydrochloric acid.
All the above reagents are chemically pure.
4.4 Sampling
Collect suspended dust near the breathing zone where workers often work. Collect about 0.2g of dust at the maximum flow rate using the sampling method with a filter membrane diameter of 75mm, or use other appropriate sampling methods for sampling; when limited by sampling conditions, settle dust can be collected at the height of the breathing zone.
4.5 Analysis steps
4.5.1 Place the collected dust sample in an oven at 105±3.℃ for 12h, cool it slightly, and place it in a desiccator for later use. If the dust particles are large, grind them with an agate mortar until they feel smooth when rubbed by hand. 4.5.2 Accurately weigh 0.1~0.2g of dust sample into a 50ml conical flask. 4.5.9 If the sample contains coal, other carbon and organic dust, it should be placed in a porcelain crucible and burned at 800~900℃ for more than 30min to completely ash the carbon and organic matter. After cooling, wash the residue into the conical flask with pyrophosphoric acid. If it contains sulfide minerals (such as pyrite, chalcopyrite, molten iron, etc.), add several milligrams of crystalline ammonium nitrate into the conical flask. 4.5.4 Take 15ml of pyrophosphoric acid with a base, pour it into the conical flask, and shake it to make the sample completely wet. 4.5.5. Place the conical flask on an adjustable electric furnace, heat it quickly to 245-250℃, keep it for 15 minutes, and stir it continuously with a glass rod with a thermometer.
.5.6 Remove the conical flask, cool it to 100-150℃ at room temperature, and then put the conical flask in cold water to cool it to 40-50℃. During the cooling process, add 50-80℃ distilled water to dilute it to 40-45ml. When diluting, add water while stirring vigorously. 4.5.7 Carefully transfer the contents of the conical flask to a beaker, and then rinse the thermometer, glass rod and conical flask with hot filtered distilled water. Pour the washing liquid into the beaker, dilute it to 150-200ml with distilled water, and stir it with a glass rod. 4.5.8 Place the beaker on the electric stove and boil the contents. Filter with gray filter paper while it is hot (add paper pulp when there are dust particles in the filtrate). Do not pour too much filtrate. Generally, it should be about two-thirds of the filter paper. 4.5.9 After filtering, wash the beaker with 0.1N hydrochloric acid and transfer it to the funnel. Rinse the sediment on the filter paper E for 3 to 5 times, and then wash it with hot distilled water until there is no acidic reaction (can be tested with pH test paper). If platinum is used, wash it until the phosphate reaction occurs and then wash it three times (see 4.8 for the test method). The above process should be completed in the day. 4.5.10 Fold the filter paper with sediment several times, put it in a constant amount of porcelain block, dry it in an oven at 80, and then put it in the electric furnace F for low-temperature carbonization. Cover it and leave a small gap during carbonization, then put it in a high-temperature electric furnace (800-900℃) and smoke it for 30 minutes. Take out the filter paper, cool it slightly at room temperature, and then put it back in! Cool the desiccator for 1 hour, weigh to a constant weight and record the result. GB 5748-85
4.6 The free silicon cyanide content in the dust is calculated according to formula (3): SiO,(F) =
-free silicon dioxide content, %;
Where: SiO,(F) -
m-ground crucible mass, g
-average weight of sediment, g,
G-dust sample mass, g.
4.7 Treatment of dust containing insoluble substances
4.7.1 When the dust sample contains substances that are difficult to be dissolved by pyrophosphoric acid (such as silicon carbide, chlorite, tourmaline, topaz, etc.), it needs to be treated with hydrofluoric acid in a platinum crucible.
4.7.2 Add a few drops of 1:1 sulfuric acid to the platinum crucible to wet the sediment completely. Then add 5-10 ml of 40% hydrofluoric acid (in a fume hood), heat it slightly to dissolve the free silicon oxide in the sediment, and continue heating and evaporation until no smoke is emitted (to prevent boiling). Then burn it at 900℃ and weigh it to a constant weight.
4.7.3 The amount of free silicon oxide after the insoluble material is buried is calculated according to formula (4): m2-m2×100
Si0,(F)=
Where: m: - mass of the sediment after hydrofluoric acid treatment, g, and the meanings of other symbols are the same as those in formula (3). 4.8 Test method for phosphate (PO)
4.8.1 Principle
Phosphoric acid and ammonium molybdate are reduced with ascorbic acid at pH 4.1 to produce a colorimetric product. 4.8.2. Preparation of test solution
4.8.2.1 Acetate buffer (pH 4.1) Take 0.025N sodium acetate solution and 0.1V acetic acid solution and mix them in equal volumes. 4.8.2.2 1% ascorbic acid solution (store in refrigerator). 4.8.2.3 Ammonium molybdate solution Take 2.5g ammonium molybdate and dissolve it in 100ml 0.05N sulfuric acid (prepare it before use). 4.8.3 Test method
4.8.3.1 When measuring, dilute 4.8.2.2 and 4.8.2.3 solutions 10 times with 1.8.2.1 solution respectively. 4.8.a.2 Take 1ml of filtrate and add 4.5ml of each of the above solutions and mix well. Let it stand for 20 minutes. If phosphate ion is present, color will be displayed. 4.9 This method is the basic method. When other methods are used, this method must be used as the basis. 5 Determination of dust dispersion
5.1 Filter membrane dissolution smear method
5.1.1 Principle
The sampled filter membrane is dissolved in an organic solvent to form a suspension of powder particles, which is then prepared as a specimen and measured under a microscope. 5.1.2 Reagents and equipment
5.1.2.1 Acetic acid (chemically pure).
5.1.2.2 Porcelain crucible (25 ml) and small beaker (25 ml).
5.1.2.3 Glass rod.
5.1.2.4 Glass dropper or pipette.
5.1.2.5 Slide (75×25×1 mm).
5.1.2.6 Microscope.
5.1.2.7 Heliostat micrometer.
5.1.2.8 Objective micrometer,
The above equipment must be cleaned before use to avoid dust pollution. -(4)
5.1.3 Operation steps
GB 5748--85
5.1.3.1 Place the filter membrane with dust in a porcelain flask or a small beaker, add 1-2 ml of acetic acid with a pipette, and stir thoroughly with a glass rod to make a uniform dust suspension. Immediately use a dropper to absorb a drop and drop it on the slide. Use another slide to slide at a 45" angle and stick a label, number, and indicate the sampling location and date. 5.1.3.2 If the dust on the smear is dense and affects the determination during microscopic examination, Add an appropriate amount of acetic acid to dilute and prepare the specimen again. 5.1.3.3 The prepared specimen should be stored in a glass plate to avoid contamination by external dust. 5.1.3.4 At a magnification of 400 to 600 times, use the objective micrometer to calibrate the spacing of each scale of the eyepiece micrometer, that is, place the objective micrometer on the microscope stage and the eyepiece micrometer in the meniscus. Under a low-power microscope (objective 4× or 10×), find the scale line of the objective micrometer and mark it. Move the objective micrometer to the center of the field of view, then change to the magnification required for measurement, and make any scale of the objective micrometer overlap with any scale of the eyepiece micrometer in the center of the field of view. Then find the scale line where the two scales overlap again, count the scale numbers of the overlapping parts of the two micrometers, and calculate the distance between each scale of the eyepiece micrometer. 5.1.3.5 Determination of dispersion
Remove the objective micrometer, place the powder sample on the stage, first use the low-power microscope to find the dust particles, and then use Observe at 400-600 times. Use an eyepiece micrometer to selectively measure the size of dust particles in sequence. If you encounter a long diameter, measure the long diameter; if you encounter a short diameter, measure the short diameter. Measure at least 200 dust particles, record according to the table below, and calculate the fraction.
Powder number dispersion measurement record table
Particle, diameter, μm
Number of dust particles, pieces
Percentage, path
5.1.3.6 "This method is not applicable to dust and fibrous dust that can be dissolved in dry organic solvents. This: Natural sedimentation method. 5.2 Natural sedimentation method
5.2.1 Principle
Collect dust-laden air in a sedimentator, let the dust particles settle naturally on the cover glass, and measure under a microscope. 5.2.2 Equipment
5.2.2.1 Green sedimentator.
5.2.2.2 Cover glass (18×18mm)
5.2.2.3 Slide (75×25×1mm) 05.2.2.4 Microscope.
5.2.2.5 Micrometer.
5.2.2.6 Micrometer.
5.2.3 Operation steps
5.2.3.1 Soak the cover glass in chromic acid solution, rinse with water, and then clean it with 95% ethanol. Then put it in the groove of the settler, push the slide to be flush with the base, and cover the cylinder cover for sampling. 5.2.3.2 When sampling, push the submersible plate toward the groove until the cylinder is outside the base, remove the cylinder cover, move it up and down several times to allow dust-laden air to enter the cylinder, cover the cylinder cover, and push the slide to be flush with the base. Then place the sedimentation vessel horizontally for 3 hours to allow the whole particles to naturally fall on the cover glass.
5.2.3.3 Push the slide out of the base, take out the cover plate and stick it on the sample plate, number it, and indicate the date and location of the sample. Then measure it under a microscope.
5.2.3.4 The measurement and calculation of dust dispersion are the same as 5.1.3.5. GB5748$5
Appendix
Main technical indicators of dust measuring equipment
(Supplement)
A, 1 Filter membrane The retention rate of the filter membrane, when using oil mist with a diameter of 0.3μm for detection, should not be less than 99%, the resistance of the filter membrane, when sampling with a flow rate of 201/mi and a filtration area of 8cm2, should not be greater than 1000Pa; the stability of the filter membrane quality, the change in the quality of the filter membrane caused by the change in atmospheric humidity should not be greater than 0.1%. A2 Air tightness of the sampling head: Place the sampling head with a plastic film on the filter membrane in a beaker of water, and send air into the sampling head to pressurize it. When the pressure difference reaches 1000Pa, bubbles should appear in the water. A.3 Flowmeter: The flowmeter accuracy is ±2.5%. A, 4 The vacuum fan should be able to operate continuously for 100 minutes or more, the sampling flow rate (with filter membrane) should be greater than 151/min, and the negative pressure should be greater than 1500Pa. mB1 point
GB5748-85
Appendix B
Determination of dust measuring points and sampling positions in factories
(reference)
B.1.1 "When there are multiple dust-generating equipment in a factory\building, select one measuring point for less than three units, two measuring points for four to ten units, and at least one measuring point for more than ten units. When dust-generating equipment handles different materials, measuring points shall be set according to the type of materials, and one dust measuring point shall be set for a single dust-generating equipment.
B.1.2 Dust measuring points shall be set for mobile dust-generating equipment according to the length of the regular moving range. One for less than 20m, and one for 20m For the above, one dust measuring point shall be set up at each loading and unloading place.
B.1.3 In the centralized control room, at least one dust measuring point shall be set up, but there shall be no less than one dust measuring point at the operating post. B.1.4 For belts with a length of less than 10m, one dust measuring point shall be set up, and for belts with a length of more than 10m, at least one dust measuring point shall be set up at the head and tail of the belt. A high-type belt transport transfer station shall have one dust measuring point at the head and tail of the machine, and a low-type transfer station shall have one dust measuring point. B,2 Sampling position
The sampling position shall be selected in the breathing zone close to the operating post (generally about 1.5m) or the dust-generating point. C.1 Measuring point
GB5748—85
Appendix C
Determination of dust measurement points and sampling locations for underground mine tunnel projects (reference)
C.1.1 For T-type working faces with a digging length of more than 10m, brushing, bottom pulling, top picking and digging chambers with continuous operations for more than five shifts, a dust measurement point shall be set for each working face. For working faces with more than one shift, only one rock drilling dust measurement point shall be calculated. C,1.2 For chamber-type mining areas, dust measurement points shall be set according to the type of operation. For road-type mining areas, measurement points shall be set according to the number of operating tunnels. For mining areas with a cutting volume of more than 50m, one dust measurement point shall be set. When chiseling funnels, one ore block shall be used as one dust measurement point. C1.3 For hoppers, ore shall be discharged according to the mining area. Dust measuring points are set up in the field, but when several adjacent mines are unloading at the same time in the inter-air flow, only 1 dust measuring point is set up. For the carpet-type mining method, dust measuring points are set up according to the number of tunnels. When using a belt transfer machine for transportation, 1 dust measuring point is set up for each belt transfer machine, loading station, tipping cage, etc. 2 dust measuring points are set up for unloading and unloading of ore. Dust measuring points are set up in the main transportation tunnel according to the number of middle sections. C.1.4 A dust measuring point is set up in the crushing room.
C.1.5 When the number of shifts for hitting the wrong rod, mixing and spraying is more than 1 shift in a month, dust measuring points are set up respectively. C.1.6 Dust measuring points are set up in the changing room according to the number of rooms. C.2 Sampling location
C.2.1 The sampling position for drilling operations shall be set at the worker's breathing zone on the windward side 3 to 6 m from the working face. The sampling position for mechanical loading operations, simultaneous drilling and loading operations, and simultaneous operations of tunneling machines and rock loaders shall be set at the windward side 4 to 6 m from the rock loader: the manual loader shall be set in the downwind flow about 1.5 m from the rock loader. The sampling position for ordinary method excavation of the sky piece shall be set in the return air flow under the safety shed, and the sampling position for hanging tanks or climbing tanks to excavate the large and medium-sized mines shall be set in the return air flow under the left sky.
C,2.2 The sampling position for room-type and tunnel-type mine operations shall be set in the windward flow 3 to 6 m from the dust-generating point; the sampling position for multiple constant light machines operating simultaneously shall be set at a place with poor ventilation conditions. The sampling position for electric rake operations shall be set at about 1.5 m from the worker's operating location. C.2.3 The sampling position for the ore dumping and ore placing operations of wells and funnels shall be set at about 3 m on the downwind side. The sampling locations of dust-generating points such as belt transfer machines, loading stations, and tank cages are all set at 1.5 to 2 m downwind of the dust-generating points. The sampling locations of the main transport tunnels are set at locations with severe pollution. .2.4 The sampling locations for shotcrete and bolting operations are set at 5 to 10 m downwind of the upper operating location. D,1 Dust measuring points
GB5748—85
Appendix D
Determination of dust measuring points and sampling locations in Xutian mines (reference)
D,1,1 A dust measuring point is set in the driver's cab of each drilling rig (down-the-hole drill, cone drill, impact drill, etc.), and a dust measuring point is set at the drilling rig. For bench-type pneumatic drills (including light, heavy rock drills) for rock drilling, dust measuring points are set according to the working surface. D.1.2 A dust measuring point is set in the driver's cab of each electric shovel and diesel shovel, and a dust measuring point is set outside the driver's room. Each scraper has a dust measuring point in the driver's cab and a dust measuring point outside the driver's cab. Each T-2G and T-4G loader has a dust measuring point. Each manual excavation work surface has a dust measuring point. D1. A dust measuring point is set in the driver's cab of vehicles (cars, electric locomotives, diesel locomotives, bulldozers and rollers, etc.). Other transportation (cableways, belts, ramps, flatbed trucks, manual transportation, etc.) have dust measuring points at transfer points or drop points. D,,4-A dust measuring point is set on the working step pavement. 2 to 4 dust measuring points are set on the permanent pavement (between the mining site and the ore unloading bin or the stone quarry).
D,1.5 A dust measuring point is set in each secondary blasting and rock drilling area, D.1.6 A dust measuring point is set at each waste rock yard, ore unloading bin, and transfer station. D.1.7 A dust measuring point is set for each independent wind source. D.1.8 Dust measuring points shall be set up at the ore chute and the ore discharge point. A dust measuring point shall be set up at the metering room and the mobile air compressor station. A dust measuring point shall be set up at the maintenance yard, material warehouse, winch room, pump room and rest room. D.2 Sampling location
D.2.1 The sampling location in the driver's room of electric shovel, drilling rig, scraper, vehicle, etc. shall be set within the driver's breathing zone. D.2 The sampling location outside the drilling rig shall be set on the leeward side 3 to 5 meters away from the drilling rig. The sampling location outside the scraper shall be set on the leeward side 1.5-3 meters away from the rock shoveling place.
The sampling location of the bench-type pneumatic drill for rock removal shall be set on the leeward side 1.5 to 3 meters away from the worker's operation place. D.2. The sampling location outside the electric shovel shall be set on the leeward side of the midpoint between the loading and unloading of the electric shovel bucket. For buckets with a capacity of 1m3, the measuring point is about 15m from the midpoint; for buckets with a capacity of 3→5m, the measuring point is 20 to 30m; for buckets with a capacity of more than 8m3, the measuring point is 30-40m. The sampling position for the working surface of T-2G, T-4G and other loaders and manual excavation is set on the F windward side 1.5 to 3m away from the excavation. D.2.4 The sampling position for other transportation operations other than motor vehicles is set on the leeward side 1.5 to 3m away from the transfer point or the place where the material is dropped. The sampling position for factory-made step pavement and permanent pavement is set on the leeward side of the dust-prone area, 5 to 7m away from the center line of the pavement. D,2,5- The sampling position for the secondary blasting rock drilling area is set on the leeward side 3 to 5m away from the rock drilling. D.2,6: The sampling positions for the quarry, unloading warehouse and transfer station are all set on the leeward side of the unloading place. The distance is: 3-5m for manual unloading, 5-10m for locomotive hauling below 0t/15-20m for locomotive hauling above 30t. .2.7 The sampling position of the independent air source is set on the actual windward side of the mining site, and should not be affected by any dust-laden airflow in the site. The sampling position for slitting and dumping, and ore discharge operations is set on the downwind side 5-10m away from the parallel port. The sampling positions of metering rooms, mobile air compressor stations, maintenance yards, pump rooms and other places are set at the height of the workers' operating breathing zone. E.1 Dust measurement points
GB5748-85
Appendix E
Determination of dust measurement points and sampling positions when handling and storing dust-generating goods at stations, docks and warehouses
(reference)
E.1.1 Dust measurement points are set at stations, docks, warehouses, vehicles and ships and other places where goods are loaded and unloaded, and one dust measurement point is set at each belt conveyor 1.
E.1.2 A dust measuring point shall be set up at each station, wharf and warehouse where goods are stored. E.1,3 When goods are transported manually, if the round trip distance exceeds 30m, in addition to the dust measuring point at the loading and unloading place, a dust measuring point shall be set up in the middle. E.1.4 When drying food, a dust measuring point shall be set up. E.1.5 In the warehouse where goods are stored, when dust is generated during the packaging and storage process, a dust measuring point shall be set up at the packaging and distribution place. E.2 Sampling position
The sampling position is generally set on the leeward side at a height of about 2m from the workers' breathing zone. For grain storage side samples, the distance should be about 10m. Additional remarks:
This standard was proposed by the Department of Health and Epidemic Prevention of the Ministry of Health and the Labor Protection Department of the Ministry of Labor and Personnel. This standard was drafted by the Institute of Hygiene of the Chinese Academy of Preventive Medicine and the Institute of Safety Technology of the Ministry of Metallurgy. The main drafters of this standard are Feng Bingheng, Fu Shaochang, Li Liexun, Xu Saitong, Huang Yanlong, Huang Dewei, Tang Chanpei, Zhang Weichang, Liu Houjin, and Wang Dexuan.2 Mobile dust-generating equipment shall be equipped with dust measuring points according to the length of the regular moving range. For equipment below 20m, one dust measuring point shall be set; for equipment above 20m, one dust measuring point shall be set at each loading and unloading place.
B.1.3 In the centralized control room, at least one dust measuring point shall be set, but the operation post shall not be less than one dust measuring point. B.1.4 For belts below 10m in length, one dust measuring point shall be set; for belts above 10m, one dust measuring point shall be set at the head and tail of the belt. A dust measuring point shall be set at the head and tail of the high-type belt transport transfer station, and one dust measuring point shall be set at the low-type transfer station. B,2 Sampling position
The sampling position shall be selected in the breathing zone close to the operation post (generally about 1.5m) or the dust-generating point. C.1 Measuring points
GB5748—85
Appendix C
Determination of dust measuring points and sampling locations for underground mine tunnel projects (reference)
C.1.1 For T-type working faces with a digging length of more than 10m, brushing, bottom pulling, top picking and digging ketone chambers with continuous operation for more than five shifts, one dust measuring point shall be set for each working face. For working faces with more than one shift, only one rock drilling dust measuring point shall be calculated. C,1.2· Dust measuring points shall be set according to the operation type in the alkali chamber type stope. Dust measuring points are set according to the number of working tunnels in the road type mining area. When the cutting volume is less than 50m, one dust measuring point is set. When the funnel is chiseled, one ore block is used as one dust measuring point. C1.3 Dust measuring points are set according to the mining area when the hopper is used for ore discharge. However, when several adjacent mining areas are used for ore discharge at the same time in the inter-wind flow, only one dust measuring point is set. Dust measuring points are set according to the number of tunnels when the carpet type mining method is used for ore discharge. When using a belt conveyor for transportation, each belt conveyor, Each loading station, tipping cage, etc. shall be equipped with: 1 dust measuring point. 2 dust measuring points shall be set for the unloading and unloading of ore in the chute. Dust measuring points shall be set up in the main transportation tunnel according to the number of middle sections. C.1.4 A dust measuring point shall be set up in the crushing room.
C.1.5 Dust measuring points shall be set up respectively when the rod driving, mixing and spraying are more than 1 shift in a month. C.1.6 Dust measuring points shall be set up in the changing room according to the number of rooms. C.2 Sampling location
C.2.1 The sampling location for the chiseling operation shall be set at the workers’ breathing zone on the windward side 3 to 6 m away from the working face. The sampling location for mechanical loading operation, simultaneous operation of drilling and loading, and simultaneous operation of tunneling machine and rock loader shall be set at the windward side 4 to 6 m away from the rock loader: the sampling location for manual loader shall be set at about 1.5 m away from the rock loader. m in the downwind flow. The sampling position for conventional tunneling is set in the return air flow under the safety shed, and the sampling position for hanging tanks or climbing tanks is set in the return air flow under the left skylight.
C,2.2 The sampling position for room-type and tunnel-type mining operations is set in the return air flow 3 to 6 m away from the dust-generating point; the sampling position for multiple constant-speed mining machines operating at the same time is set at a location with poor ventilation conditions. The sampling position for electric rake operations is set at about 1.5 m away from the workers' operating location. C.2.3 The sampling position for the dumping and placing of ore in wells and funnels is set at about 3 m on the downwind side. The sampling positions of dust-generating points such as belt transfer machines, loading stations, and tank cages are all set 1.5 to 2 m downwind of the dust-generating point. m. The sampling location of the main transport tunnel shall be set at the place with serious pollution. .2.4 The sampling location of grouting and bolting operations shall be set at 5 to 10 m downwind from the place where the upper operator operates. D,1 Dust measuring point
GB5748—85
Appendix D
Determination of dust measuring points and sampling locations in mines (reference)
D,1,1 A dust measuring point shall be set in the driver's cab of each drilling rig (down-the-hole drill, rotary drill, impact drill, etc.), and a dust measuring point shall be set at the drilling rig. For bench-type pneumatic drills (including light, heavy rock drills), dust measuring points shall be set according to the working face. D.1.2 Each electric shovel, diesel There is one dust measuring point in the driver's cab of the shovel and one dust measuring point outside the driver's cab. There is one dust measuring point in the driver's cab of each scraper and one dust measuring point outside the driver's cab. There is one dust measuring point for each T-2G and T-4G loader. There is one dust measuring point for each manual excavation working surface. D1. There is one dust measuring point in the driver's cab of vehicles (cars, electric locomotives, diesel locomotives, bulldozers and rollers, etc.). Other transportation (cableways, belts, ramps, flatbed trucks, manual transportation, etc.) are equipped with dust measuring points at transfer points or drop points. D,,4- There are one dust measuring point on the working step pavement. There are 2 to 4 dust measuring points on the permanent pavement (between the mining site and the ore unloading bin or the stone quarry).
D,1.5 There is one dust measuring point in each secondary blasting and rock drilling area, D.1.6 There is one dust measuring point at each waste rock field, ore unloading bin, and transfer station. D.1.7 There is one dust measuring point for each independent wind source. D.1.8 Dust measuring points shall be set up at the ore chute and the ore discharge point. A dust measuring point shall be set up at the metering room and the mobile air compressor station. A dust measuring point shall be set up at the maintenance yard, material warehouse, winch room, pump room and rest room. D.2 Sampling location
D.2.1 The sampling location in the driver's room of electric shovel, drilling rig, scraper, vehicle, etc. shall be set within the driver's breathing zone. D.2 The sampling location outside the drilling rig shall be set on the leeward side 3 to 5 meters away from the drilling rig. The sampling location outside the scraper shall be set on the leeward side 1.5-3 meters away from the rock shoveling place.
The sampling location of the bench-type pneumatic drill for rock removal shall be set on the leeward side 1.5 to 3 meters away from the worker's operation place. D.2. The sampling location outside the electric shovel shall be set on the leeward side of the midpoint between the loading and unloading of the electric shovel bucket. For buckets with a capacity of 1m3, the measuring point is about 15m from the midpoint; for buckets with a capacity of 3→5m, the measuring point is 20 to 30m; for buckets with a capacity of more than 8m3, the measuring point is 30-40m. The sampling position for the working surface of T-2G, T-4G and other loaders and manual excavation is set on the F windward side 1.5 to 3m away from the excavation. D.2.4 The sampling position for other transportation operations other than motor vehicles is set on the leeward side 1.5 to 3m away from the transfer point or the place where the material is dropped. The sampling position for factory-made step pavement and permanent pavement is set on the leeward side of the dust-prone area, 5 to 7m away from the center line of the pavement. D,2,5- The sampling position for the secondary blasting rock drilling area is set on the leeward side 3 to 5m away from the rock drilling. D.2,6: The sampling positions for the quarry, unloading warehouse and transfer station are all set on the leeward side of the unloading place. The distance is: 3-5m for manual unloading, 5-10m for locomotive hauling below 0t/15-20m for locomotive hauling above 30t. .2.7 The sampling position of the independent air source is set on the actual windward side of the mining site, and should not be affected by any dust-laden airflow in the site. The sampling position for slitting and dumping, and ore discharge operations is set on the downwind side 5-10m away from the parallel port. The sampling positions of metering rooms, mobile air compressor stations, maintenance yards, pump rooms and other places are set at the height of the workers' operating breathing zone. E.1 Dust measurement points
GB5748-85
Appendix E
Determination of dust measurement points and sampling positions when handling and storing dust-generating goods at stations, docks and warehouses
(reference)
E.1.1 Dust measurement points are set at stations, docks, warehouses, vehicles and ships and other places where goods are loaded and unloaded, and one dust measurement point is set at each belt conveyor 1.
E.1.2 A dust measuring point shall be set up at each station, wharf and warehouse where goods are stored. E.1,3 When goods are transported manually, if the round trip distance exceeds 30m, in addition to the dust measuring point at the loading and unloading place, a dust measuring point shall be set up in the middle. E.1.4 When drying food, a dust measuring point shall be set up. E.1.5 In the warehouse where goods are stored, when dust is generated during the packaging and storage process, a dust measuring point shall be set up at the packaging and distribution place. E.2 Sampling position
The sampling position is generally set on the leeward side at a height of about 2m from the workers' breathing zone. For grain storage side samples, the distance should be about 10m. Additional remarks:
This standard was proposed by the Department of Health and Epidemic Prevention of the Ministry of Health and the Labor Protection Department of the Ministry of Labor and Personnel. This standard was drafted by the Institute of Hygiene of the Chinese Academy of Preventive Medicine and the Institute of Safety Technology of the Ministry of Metallurgy. The main drafters of this standard are Feng Bingheng, Fu Shaochang, Li Liexun, Xu Saitong, Huang Yanlong, Huang Dewei, Tang Chanpei, Zhang Weichang, Liu Houjin, and Wang Dexuan.2 Mobile dust-generating equipment shall be equipped with dust measuring points according to the length of the regular moving range. For equipment below 20m, one dust measuring point shall be set; for equipment above 20m, one dust measuring point shall be set at each loading and unloading place.
B.1.3 In the centralized control room, at least one dust measuring point shall be set, but the operation post shall not be less than one dust measuring point. B.1.4 For belts below 10m in length, one dust measuring point shall be set; for belts above 10m, one dust measuring point shall be set at the head and tail of the belt. A dust measuring point shall be set at the head and tail of the high-type belt transport transfer station, and one dust measuring point shall be set at the low-type transfer station. B,2 Sampling position
The sampling position shall be selected in the breathing zone close to the operation post (generally about 1.5m) or the dust-generating point. C.1 Measuring points
GB5748—85
Appendix C
Determination of dust measuring points and sampling locations for underground mine tunnel projects (reference)
C.1.1 For T-type working faces with a digging length of more than 10m, brushing, bottom pulling, top picking and digging ketone chambers with continuous operation for more than five shifts, one dust measuring point shall be set for each working face. For working faces with more than one shift, only one rock drilling dust measuring point shall be calculated. C,1.2· Dust measuring points shall be set according to the operation type in the alkali chamber type stope. Dust measuring points are set according to the number of working tunnels in the road type mining area. When the cutting volume is less than 50m, one dust measuring point is set. When the funnel is chiseled, one ore block is used as one dust measuring point. C1.3 Dust measuring points are set according to the mining area when the hopper is used for ore discharge. However, when several adjacent mining areas are used for ore discharge at the same time in the inter-wind flow, only one dust measuring point is set. Dust measuring points are set according to the number of tunnels when the carpet type mining method is used for ore discharge. When using a belt conveyor for transportation, each belt conveyor, Each loading station, tipping cage, etc. shall be equipped with: 1 dust measuring point. 2 dust measuring points shall be set for the unloading and unloading of ore in the chute. Dust measuring points shall be set up in the main transportation tunnel according to the number of middle sections. C.1.4 A dust measuring point shall be set up in the crushing room.
C.1.5 Dust measuring points shall be set up respectively when the rod driving, mixing and spraying are more than 1 shift in a month. C.1.6 Dust measuring points shall be set up in the changing room according to the number of rooms. C.2 Sampling location
C.2.1 The sampling location for the chiseling operation shall be set at the workers’ breathing zone on the windward side 3 to 6 m away from the working face. The sampling location for mechanical loading operation, simultaneous operation of drilling and loading, and simultaneous operation of tunneling machine and rock loader shall be set at the windward side 4 to 6 m away from the rock loader: the sampling location for manual loader shall be set at about 1.5 m away from the rock loader. m in the downwind flow. The sampling position for conventional tunneling is set in the return air flow under the safety shed, and the sampling position for hanging tanks or climbing tanks is set in the return air flow under the left skylight.
C,2.2 The sampling position for room-type and tunnel-type mining operations is set in the return air flow 3 to 6 m away from the dust-generating point; the sampling position for multiple constant-speed mining machines operating at the same time is set at a location with poor ventilation conditions. The sampling position for electric rake operations is set at about 1.5 m away from the workers' operating location. C.2.3 The sampling position for the dumping and placing of ore in wells and funnels is set at about 3 m on the downwind side. The sampling positions of dust-generating points such as belt transfer machines, loading stations, and tank cages are all set 1.5 to 2 m downwind of the dust-generating point. m. The sampling location of the main transport tunnel shall be set at the place with serious pollution. .2.4 The sampling location of grouting and bolting operations shall be set at 5 to 10 m downwind from the place where the upper operator operates. D,1 Dust measuring point
GB5748—85
Appendix D
Determination of dust measuring points and sampling locations in mines (reference)
D,1,1 A dust measuring point shall be set in the driver's cab of each drilling rig (down-the-hole drill, rotary drill, impact drill, etc.), and a dust measuring point shall be set at the drilling rig. For bench-type pneumatic drills (including light, heavy rock drills), dust measuring points shall be set according to the working face. D.1.2 Each electric shovel, diesel There is one dust measuring point in the driver's cab of the shovel and one dust measuring point outside the driver's cab. There is one dust measuring point in the driver's cab of each scraper and one dust measuring point outside the driver's cab. There is one dust measuring point for each T-2G and T-4G loader. There is one dust measuring point for each manual excavation working surface. D1. There is one dust measuring point in the driver's cab of vehicles (cars, electric locomotives, diesel locomotives, bulldozers and rollers, etc.). Other transportation (cableways, belts, ramps, flatbed trucks, manual transportation, etc.) are equipped with dust measuring points at transfer points or drop points. D,,4- There are one dust measuring point on the working step pavement. There are 2 to 4 dust measuring points on the permanent pavement (between the mining site and the ore unloading bin or the stone quarry).
D,1.5 There is one dust measuring point in each secondary blasting and rock drilling area, D.1.6 There is one dust measuring point at each waste rock field, ore unloading bin, and transfer station. D.1.7 There is one dust measuring point for each independent wind source. D.1.8 Dust measuring points shall be set up at the ore chute and the ore discharge point. A dust measuring point shall be set up at the metering room and the mobile air compressor station. A dust measuring point shall be set up at the maintenance yard, material warehouse, winch room, pump room and rest room. D.2 Sampling location
D.2.1 The sampling location in the driver's room of electric shovel, drilling rig, scraper, vehicle, etc. shall be set within the driver's breathing zone. D.2 The sampling location outside the drilling rig shall be set on the leeward side 3 to 5 meters away from the drilling rig. The sampling location outside the scraper shall be set on the leeward side 1.5-3 meters away from the rock shoveling place.
The sampling location of the bench-type pneumatic drill for rock removal shall be set on the leeward side 1.5 to 3 meters away from the worker's operation place. D.2. The sampling location outside the electric shovel shall be set on the leeward side of the midpoint between the loading and unloading of the electric shovel bucket. For buckets with a capacity of 1m3, the measuring point is about 15m from the midpoint; for buckets with a capacity of 3→5m, the measuring point is 20 to 30m; for buckets with a capacity of more than 8m3, the measuring point is 30-40m. The sampling position for the working surface of T-2G, T-4G and other loaders and manual excavation is set on the F windward side 1.5 to 3m away from the excavation. D.2.4 The sampling position for other transportation operations other than motor vehicles is set on the leeward side 1.5 to 3m away from the transfer point or the place where the material is dropped. The sampling position for factory-made step pavement and permanent pavement is set on the leeward side of the dust-prone area, 5 to 7m away from the center line of the pavement. D,2,5- The sampling position for the secondary blasting rock drilling area is set on the leeward side 3 to 5m away from the rock drilling. D.2,6: The sampling positions for the quarry, unloading warehouse and transfer station are all set on the leeward side of the unloading place. The distance is: 3-5m for manual unloading, 5-10m for locomotive hauling below 0t/15-20m for locomotive hauling above 30t. .2.7 The sampling position of the independent air source is set on the actual windward side of the mining site, and should not be affected by any dust-laden airflow in the site. The sampling position for slitting and dumping, and ore discharge operations is set on the downwind side 5-10m away from the parallel port. The sampling positions of metering rooms, mobile air compressor stations, maintenance yards, pump rooms and other places are set at the height of the workers' operating breathing zone. E.1 Dust measurement points
GB5748-85
Appendix E
Determination of dust measurement points and sampling positions when handling and storing dust-generating goods at stations, docks and warehouses
(reference)
E.1.1 Dust measurement points are set at stations, docks, warehouses, vehicles and ships and other places where goods are loaded and unloaded, and one dust measurement point is set at each belt conveyor 1.
E.1.2 A dust measuring point shall be set up at each station, wharf and warehouse where goods are stored. E.1,3 When goods are transported manually, if the round trip distance exceeds 30m, in addition to the dust measuring point at the loading and unloading place, a dust measuring point shall be set up in the middle. E.1.4 When drying food, a dust measuring point shall be set up. E.1.5 In the warehouse where goods are stored, when dust is generated during the packaging and storage process, a dust measuring point shall be set up at the packaging and distribution place. E.2 Sampling position
The sampling position is generally set on the leeward side at a height of about 2m from the workers' breathing zone. For grain storage side samples, the distance should be about 10m. Additional remarks:
This standard was proposed by the Department of Health and Epidemic Prevention of the Ministry of Health and the Labor Protection Department of the Ministry of Labor and Personnel. This standard was drafted by the Institute of Hygiene of the Chinese Academy of Preventive Medicine and the Institute of Safety Technology of the Ministry of Metallurgy. The main drafters of this standard are Feng Bingheng, Fu Shaochang, Li Liexun, Xu Saitong, Huang Yanlong, Huang Dewei, Tang Chanpei, Zhang Weichang, Liu Houjin, and Wang Dexuan.3. Dust measuring points shall be set up according to the mining area when the ore is discharged from the hopper. However, when several adjacent mining areas are discharged at the same time in the inter-wind flow, only 1 dust measuring point shall be set up. When the ore is discharged by the carpet road type mining method, dust measuring points shall be set up according to the number of tunnels. When the belt transfer machine is used for transportation, 1 dust measuring point shall be set up for each belt transfer machine, loading station, tipping cage, etc. 2 dust measuring points shall be set up for the unloading and discharge of ore in the chute. Dust measuring points shall be set up according to the number of middle sections in the main transportation tunnel. C.1.4 3 dust measuring points shall be set up in the crushing room. C.1.5 4 dust measuring points shall be set up for the driving rod, mixing and spraying when the number of shifts is more than 10 in a month. C.1.6 4 dust measuring points shall be set up in the changing room according to the number of rooms. C.2 Sampling location C.2.1 The sampling location for the chiseling operation shall be set up at the worker's breathing zone on the windward side 3 to 6 m away from the working face. The sampling position for mechanical loading, simultaneous drilling and loading, and simultaneous operation of tunneling machine and rock loader shall be set at the windward side 4 to 6 m away from the rock loader; the sampling position for manual loading shall be set in the downwind flow about 1.5 m away from the rock loader. The sampling position for ordinary method excavation is set in the return air flow under the safety shed, and the sampling position for hanging tank or climbing tank excavation is set in the return air flow under the left sky.
C,2.2 The sampling position for room-type and tunnel-type stope operations shall be set in the windward flow 3 to 6 m away from the dust-generating point; the sampling position for simultaneous operation of multiple light machines shall be set at a location with poor ventilation conditions. The sampling position for electric rake operation shall be set at about 1.5 m away from the worker's operating location. C.2.3 The sampling position for the dumping and placing of ore in wells and funnels shall be set at about 3 m on the downwind side. The sampling locations of dust-generating points such as belt transfer machines, loading stations, and tank cages are all set at 1.5 to 2 m downwind of the dust-generating points. The sampling locations of the main transport tunnels are set at locations with severe pollution. .2.4 The sampling locations for shotcrete and bolting operations are set at 5 to 10 m downwind of the upper operating location. D,1 Dust measuring points
GB5748—85
Appendix D
Determination of dust measuring points and sampling locations in Xutian mines (reference)
D,1,1 A dust measuring point is set in the driver's cab of each drilling rig (down-the-hole drill, cone drill, impact drill, etc.), and a dust measuring point is set at the drilling rig. For bench-type pneumatic drills (including light, heavy rock drills) for rock drilling, dust measuring points are set according to the working surface. D.1.2 A dust measuring point is set in the driver's cab of each electric shovel and diesel shovel, and a dust measuring point is set outside the driver's room. Each scraper has a dust measuring point in the driver's cab and a dust measuring point outside the driver's cab. Each T-2G and T-4G loader has a dust measuring point. Each manual excavation work surface has a dust measuring point. D1. A dust measuring point is set in the driver's cab of vehicles (cars, electric locomotives, diesel locomotives, bulldozers and rollers, etc.). Other transportation (cableways, belts, ramps, flatbed trucks, manual transportation, etc.) have dust measuring points at transfer points or drop points. D,,4-A dust measuring point is set on the working step pavement. 2 to 4 dust measuring points are set on the permanent pavement (between the mining site and the ore unloading bin or the stone quarry).
D,1.5 A dust measuring point is set in each secondary blasting and rock drilling area, D.1.6 A dust measuring point is set at each waste rock yard, ore unloading bin, and transfer station. D.1.7 A dust measuring point is set for each independent wind source. D.1.8 Dust measuring points shall be set up at the ore chute and the ore discharge point. A dust measuring point shall be set up at the metering room and the mobile air compressor station. A dust measuring point shall be set up at the maintenance yard, material warehouse, winch room, pump room and rest room. D.2 Sampling location
D.2.1 The sampling location in the driver's room of electric shovel, drilling rig, scraper, vehicle, etc. shall be set within the driver's breathing zone. D.2 The sampling location outside the drilling rig shall be set on the leeward side 3 to 5 meters away from the drilling rig. The sampling location outside the scraper shall be set on the leeward side 1.5-3 meters away from the rock shoveling place.
The sampling location of the bench-type pneumatic drill for rock removal shall be set on the leeward side 1.5 to 3 meters away from the worker's operation place. D.2. The sampling location outside the electric shovel shall be set on the leeward side of the midpoint between the loading and unloading of the electric shovel bucket. For buckets with a capacity of 1m3, the measuring point is about 15m from the midpoint; for buckets with a capacity of 3→5m, the measuring point is 20 to 30m; for buckets with a capacity of more than 8m3, the measuring point is 30-40m. The sampling position for the working surface of T-2G, T-4G and other loaders and manual excavation is set on the F windward side 1.5 to 3m away from the excavation. D.2.4 The sampling position for other transportation operations other than motor vehicles is set on the leeward side 1.5 to 3m away from the transfer point or the place where the material is dropped. The sampling position for factory-made step pavement and permanent pavement is set on the leeward side of the dust-prone area, 5 to 7m away from the center line of the pavement. D,2,5- The sampling position for the secondary blasting rock drilling area is set on the leeward side 3 to 5m away from the rock drilling. D.2,6: The sampling positions for the quarry, unloading warehouse and transfer station are all set on the leeward side of the unloading place. The distance is: 3-5m for manual unloading, 5-10m for locomotive hauling below 0t/15-20m for locomotive hauling above 30t. .2.7 The sampling position of the independent air source is set on the actual windward side of the mining site, and should not be affected by any dust-laden airflow in the site. The sampling position for slitting and dumping, and ore discharge operations is set on the downwind side 5-10m away from the parallel port. The sampling positions of metering rooms, mobile air compressor stations, maintenance yards, pump rooms and other places are set at the height of the workers' operating breathing zone. E.1 Dust measurement points
GB5748-85
Appendix E
Determination of dust measurement points and sampling positions when handling and storing dust-generating goods at stations, docks and warehouses
(reference)
E.1.1 Dust measurement points are set at stations, docks, warehouses, vehicles and ships and other places where goods are loaded and unloaded, and one dust measurement point is set at each belt conveyor 1. www.bzxz.net
E.1.2 A dust measuring point shall be set up at each station, wharf and warehouse where goods are stored. E.1,3 When goods are transported manually, if the round trip distance exceeds 30m, in addition to the dust measuring point at the loading and unloading place, a dust measuring point shall be set up in the middle. E.1.4 When drying food, a dust measuring point shall be set up. E.1.5 In the warehouse where goods are stored, when dust is generated during the packaging and storage process, a dust measuring point shall be set up at the packaging and distribution place. E.2 Sampling position
The sampling position is generally set on the leeward side at a height of about 2m from the workers' breathing zone. For grain storage side samples, the distance should be about 10m. Additional remarks:
This standard was proposed by the Department of Health and Epidemic Prevention of the Ministry of Health and the Labor Protection Department of the Ministry of Labor and Personnel. This standard was drafted by the Institute of Hygiene of the Chinese Academy of Preventive Medicine and the Institute of Safety Technology of the Ministry of Metallurgy. The main drafters of this standard are Feng Bingheng, Fu Shaochang, Li Liexun, Xu Saitong, Huang Yanlong, Huang Dewei, Tang Chanpei, Zhang Weichang, Liu Houjin, and Wang Dexuan.3. Dust measuring points shall be set up according to the mining area when the ore is discharged from the hopper. However, when several adjacent mining areas are discharged at the same time in the inter-wind flow, only 1 dust measuring point shall be set up. When the ore is discharged by the carpet road type mining method, dust measuring points shall be set up according to the number of tunnels. When the belt transfer machine is used for transportation, 1 dust measuring point shall be set up for each belt transfer machine, loading station, tipping cage, etc. 2 dust measuring points shall be set up for the unloading and discharge of ore in the chute. Dust measuring points shall be set up according to the number of middle sections in the main transportation tunnel. C.1.4 3 dust measuring points shall be set up in the crushing room. C.1.5 4 dust measuring points shall be set up for the driving rod, mixing and spraying when the number of shifts is more than 10 in a month. C.1.6 4 dust measuring points shall be set up in the changing room according to the number of rooms. C.2 Sampling location C.2.1 The sampling location for the chiseling operation shall be set up at the worker's breathing zone on the windward side 3 to 6 m away from the working face. The sampling position for mechanical loading, simultaneous drilling and loading, and simultaneous operation of tunneling machine and rock loader shall be set at the windward side 4 to 6 m away from the rock loader; the sampling position for manual loading shall be set in the downwind flow about 1.5 m away from the rock loader. The sampling position for ordinary method excavation is set in the return air flow under the safety shed, and the sampling position for hanging tank or climbing tank excavation is set in the return air flow under the left sky.
C,2.2 The sampling position for room-type and tunnel-type stope operations shall be set in the windward flow 3 to 6 m away from the dust-generating point; the sampling position for simultaneous operation of multiple light machines shall be set at a location with poor ventilation conditions. The sampling position for electric rake operation shall be set at about 1.5 m away from the worker's operating location. C.2.3 The sampling position for the dumping and placing of ore in wells and funnels shall be set at about 3 m on the downwind side. The sampling locations of dust-generating points such as belt transfer machines, loading stations, and tank cages are all set at 1.5 to 2 m downwind of the dust-generating points. The sampling locations of the main transport tunnels are set at locations with severe pollution. .2.4 The sampling locations for shotcrete and bolting operations are set at 5 to 10 m downwind of the upper operating location. D,1 Dust measuring points
GB5748—85
Appendix D
Determination of dust measuring points and sampling locations in Xutian mines (reference)
D,1,1 A dust measuring point is set in the driver's cab of each drilling rig (down-the-hole drill, cone drill, impact drill, etc.), and a dust measuring point is set at the drilling rig. For bench-type pneumatic drills (including light, heavy rock drills) for rock drilling, dust measuring points are set according to the working surface. D.1.2 A dust measuring point is set in the driver's cab of each electric shovel and diesel shovel, and a dust measuring point is set outside the driver's room. Each scraper has a dust measuring point in the driver's cab and a dust measuring point outside the driver's cab. Each T-2G and T-4G loader has a dust measuring point. Each manual excavation work surface has a dust measuring point. D1. A dust measuring
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