Sampling pump, personal

British Occupational Hygiene Society (1985J The Selection and Use of Personal Sampling Pumps, Technical Guide No. 5, BOHS, Norwood, Science Reviews. 

Calibrate personal sampling pumps before and after each day of sampling, using either the electronic bubble meter method or the precision rotameter method (that has been calibrated against a bubble meter). 

The precision rotameter is a secondary calibration device. If it is to be used in place of a primary device such as a bubble meter, care must be taken to ensure that any introduced error will be minimal and noted. The precision rotameter may be used for calibrating the personal sampling pump in lieu of a bubble meter provided it is (a) Calibrated with an electronic bubble meter or a bubble meter, (b) Disassembled, cleaned as necessary, and recalibrated. It should be used with care to avoid dirt and dust contamination which may affect the flow, (c) Not used at substantially different temperature and/or pressure from those conditions present when the rotameter was calibrated against the primary source, (d) Used such that pressure drop across it is minimal. If altitude or temperature at the sampling site are substantially different from the calibration site, it is necessary to calibrate the precision rotameter at the sampling site where the same conditions are present. 

Environmental analysis entails sampling ambient air (Table 9.1) by means of a pump with subsequent analysis of the collected sample. Pumps vary from large, stationary high-volume versions to pocket-size devices used in personal dosimetry. Samples may be collected in airtight bags, or absorbed in liquids or on solid adsorbents for subsequent analysis. 

Sampling methodology has steadily improved over the years, especially in the area of integrated sampling. Personal sampling pumps with electronic flow controllers can significantly increase the accuracy of resulting sample volumes. 

The methods developed for HCCP, HCBD, and 1,2-DCP involve the collection of vapors of the compounds from air with solid sorbents in tandem with personal sampling pumps, desorption of the sorbed compounds in appropriate solvents, and analysis of the extracts by gas chromatography (GC). 

The sorbent tube is placed near the worker s breathing zone, and the outlet of the tube is attached to a calibrated personal sampling pump. A known volume of air is drawn through the tube. Alternatively, several passive charcoal badges are currently commercially available. No sampling pump is required for these devices,... 

A glass tube (6-mm I.D. by 8-mm O.D. by 3-cm long) is packed with approximately 100 mg of sorbent in a front section and 50 mg in a backup section, each separated by glass wool plugs. Sorbents of coarse mesh size ( 20/40) are used to minimize the pressure drop across the tube. A calibrated personal sampling pump draws air through the sorbent tube at a flow rate of up to 1 liter/min. 

Parker, C. D. Lee, M. B. Sharpe, J. C. "An Evaluation of Personal Sampling Pumps in Sub-Zero Temperatures " Research Triangle Institute Report for NIOSH. Contract No. 210-76-0124, September 1977. 

Estimates of inhalation contact exposure can be made by sampling air in the breathing zone of the applicator. Filter pads attached to respirators can be presumed to trap the pesticide which would have otherwise been inhaled and they can be removed and. analyzed. A second method is to use personal air sampling pumps in which air is drawn over a suitable absorbent material which can subsequently be analyzed for pesticide. 

As mentioned earlier, the personal sampling pump should be calibrated before and after sampling to determine accurately the flow rate and the volume of air sampled. A soap bubblemeter or a gasometer should be used for such calibration. 

PCBs in air may be analyzed by NIOSH Method 5503. Using a personal sampling pump, 1 to 50 L air is passed though a 13 mm glass fiber filter and through a florisil column at a flow rate of 50 to 200 mL/min. A glass fiber filter is placed in a cassette that is connected to the florisil tube. The latter contains 100 and 550 mg florisil in the front and back sections of the tube, respectively. 

Method Evaluation. Evaluation of the sampling and analytical method was accomplished by collecting and analyzing 52 samples of vinyl acetate from atmospheres at greater than 80 relative humidity according to the scheme in Table IV. Fully charged personal sampling pumps were used and performed... 

Figure 2. Calibration setup for personal sampling pump with cyclone collection...

EXPERIMENTAL The sampling and analytical method employed in determining the various solvent vapor concentrations in air are described in detail by White etal (A)and NIOSH (2), Four Bendix National Environmental Instruments Model BDX 30 Personal Samplers were used daily (one in each laboratory) with large size charcoal tubes (SKC cat no. 226-09-100) which contained two sections of activated charcoal per tube (a 400 milligram section followed by a 200 mg backup section to indicate when "breakthrough" of the main section has occurred). The sampling pumps were operated at a rate of one liter per minute and were calibrated by means of an Environmental Compliance Corporation Model 302 Universal Pump Calibrator (a device that generates a thin film of soap which is carefully timed as it traverses a very... 

Measurement of Pressure Drop. Air was pumped through the tubes by means of a personal sampling pump at a flow rate of 300 ml./ minute, as measured by a rotameter between the pump and the tube. 

In the United States, methods for several pesticides at occupational levels in air are given in the National Institute for Occupational Safety and Health (NIOSH) Manual of Analytical Methods (Eller, 1994). The NIOSH methods for organochlo-rines and organophosphates utilize small traps with a particle filter backed up by two Amberlite XAD-2 resin beds. They are designed to be used with personal sampling pumps operating at flow rates of 0.2 to 1 L/min for maximum sample volumes of 60 to 240 L. Detection limits are in the 5 ng/m to 600 ng/m range. 

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