Personal sampling methods

Hurley GF, Ketchem NH. 1978. A solid sorbent personal sampling method for the determination of acrolein in air. Am Ind Hyg Assoc J 39 615-619. 

Woebkenberg, M. L. A Comparison of Three Passive Personal Sampling Methods for Nitrogen Dioxide, Am. Ind. Hyg. Assoc. J. 43, 553 (1982)... 

A personal sampling method for common organophosphate additives in hydraulic fluids in occupational air was developed with the aim of exposure assessment in working atmospheres potentially contaminated by hydraulic fluids, simultaneously collecting both the aerosols and the vapours. The described sampler combined a glass fibre filter with a Chromosorb 106 adsorbent tube. Desorption was performed with dichloromethane for GC/MS analysis (Solbu et al. 2007). 

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). 

Other than wipe sampling of elean areas, the Site J eontraetor did not implement proeedures to evaluate the eflfeetiveness of personal deeontamination methods. Deeontaminated equipment was tested by wipe sampling. Further deeontamination was performed as neeessary until wipe samples fell below the eontraetor s trigger levels. 

TTie ability of the ventilation system to protect the worker efficiently can readily be determined by personal samples. The PIMEX method (see Chapter 12) can be used to determine the worker s exposure during various work phases. The capture efficiency as well as the supply air fraction can be measured using tracer gas techniques. Simple evaluation is carried out visually with smoke tube or pellet tests. Daily system evaluation is recommended using airflow or static pressure measurements at appropriate parts of the system. The air velocities, turbulence intensities, air temperature, mean radiant temperature, and air humidity should also be measured to provide an assessment ol thermal comfort. 

Sampling Methods From the outset of the high density lake sampling program in 1987, the application of a robust and consistent sampling protocol was considered paramount and this is still the case. Lake sediment and water sampling is performed by 2-person teams primarily from float-equipped Bell 206B helicopters. 

Development of Personal Sampling and Analytical Methods for Organochlorine Compounds... 

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). 

A method for sampling and analysis of the metallic dusts and fumes is necessary to assess the exposure of workers to these dusts. Personal sampling devices are used to collect samples from the work-place atmosphere in a representative manner. The samples are then analyzed by convenient analytical techniques such as atomic absorption spectroscopy. 

Current methods of collecting personal samples of organotin compounds produce erratic, inconsistent results. Use of the most efficient collection scheme, concentrated HNO3 in a midget impinger, is certainly unsafe. 

A universal sampler applicable to the majority of pesticides would be an ideal sampling device. In this study, personal sampling and analytical methods were developed and validated in the laboratory for determining workplace exposure to several pesticides. The major objectives of the study were to standardize on specific sampling media and to develop and validate methods using filter/ sorbent sampling trains. 

The selection of a solid sorbent for personal sampling of pesticides was based on the factors of good recovery of the sample, adequate capacity and storage stability, and contribution to overall precision and accuracy of the method as discussed earlier. The sorbent should also be inert and free of background interferences. Prewashing the sorbents before use by Soxhlet extraction with a methanol/acetone solution and drying was done to remove residual monomers, impurities, and any solvents. 

The purpose of the validation program was to assure that accurate personal sampling and analytical methods would be available for use by OSHA in monitoring for non-compliance to the OSHA permissible exposure limits (PEL s). The methods are available to others who may want to use them to determine worker exposure to the substances in the OSHA regulations. 

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. 

Exposure assessment is done under the strong assumptions that (1) an adequate model for exposure calculation is on hand and (2) sufficient data about all influential exposure factors are available. The calculation is a prognosis about the expected level of exposure or the burden. Direct methods of exposure assessment, such as personal sampling (air, radiation), duplicate studies (nutrition) and human biomonitoring, provide information on a measurement level. The exposure assessors and the risk managers should balance the reasons for using prognostic techniques instead of direct exposure measurement methods. Both should anticipate critical questions about the validity of the exposure assessment technique in the course of public risk communication. Questions heard by the authors from concerned persons include, for example ... 

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... 

In the past 20 years size-selective sampling has been applied to ambient sampling as well as personal sampling [John (1984), EPA (1987)]. A method known as the PM-10 method samples particles into two size segments, one greater than 10 pm and the other less than 10 pm (the thoracic fraction). If a conventional mass respirable sampler operates at a flow rate of 1.7 L/min to collect 3.5-pm particles with a 50 percent efficiency, what flow rate would be necessary to collect 10-pm particles with a 50 percent efficiency Assume unit-density spheres. 

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. 

Recent studies indicate the potential widespread occurrence of low-level concentrations (ng-pg L-1) of emerging pollutants such as pharmaceuticals, hormones, personal protection products, household chemicals and their metabolites in the aquatic environment (Halling-Sprensen etal., 1998 Boyd etal., 2003 Sigg etal., 2006), particularly in wastewater. Some of these compounds are of particular concern because of their high levels of biological activity. Many of these substances are present at only very low levels, and conventional sampling methods (i.e., spot sampling) often require the... 

For the evaluation of the acceptabihty of an air sample (percentage of dissatisfied persons), several methods have been apphed. Besides the yes/no classification (acceptable or not acceptable), the continuous acceptabihty scale [32] is used. The middle of the scale is indicated as the transition between just acceptable and just not acceptable. With both methods, however, large panels (up to 100 persons, depending on the statistical relevance required) of untrained persons are required. 

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