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 the sampling procedures. The set of replicate samples should be exposed to the same dust environment, either in a laboratory dust chamber or in the field. The quality control samples must be taken with the same equipment, procedures and personnel used in the routine field samples. The relative standard deviation, sr, calculated from these replicates should be recorded on control charts and action taken when the precision is out of control.

e. Jarless Method of Calibration of Cyclone Assemblies [23]

This procedure may be used in the field to calibrate an air sampling pump and a cyclone assembly without using the one-liter “calibration jar.”

(1) Connect the pump to a pressure gauge or water manometer, a light load equal to 2 to 5" H2O, and an electronic bubble meter or standard bubble tube.

(2) Adjust the pump to 1.7 L/min as indicated on the bubble meter/tube, under the light load conditions (2 to 5" H2O) as indicated on the pressure gauge or manometer.

(3) Increase the load until the pressure gauge or water manometer indicates between 25 and 35" H2O. Check the flow rate of the pump again. The flow rate should remain at 1.7 L/min ± 5%.

(4) Replace the pressure gauge or water manometer and the electronic bubble meter or standard bubble tube with the cyclone having a clean filter installed. If the loading caused by the cyclone assembly is between 2 and 5" H2O, the calibration is complete and the pump and cyclone are ready for sampling.

8. REFERENCES:

[1] First MW [1995]. Air Sampling and Analysis of Air Contaminants: An Overview. In: Cohen BS, Hering SV, Eds. Air Sampling Instruments, 8th ed. Cincinnati, OH: ACGIH, pp. 1-18.

[2] Melcher RG [1987]. Laboratory and Field Validation of Solid Sorbent Samplers. In: Taylor JK, Ed. Sampling and Calibration for Atmospheric Measurements, ASTM STP 957, Philadelphia PA: American Society for Testing and Materials, pp. 149-165.

[3] Iraneta PC, Collamati RA, Costello DN, Crowley RJ, Fernandez RL, Hopkins MR, Knowles CE, Martin DM [in press]. A validation study for a new active sampler for the analysis of formaldehyde in workplace and indoor air. Am Ind Hyg Assoc J.

[4] Kennedy ER [1988]. Sampling Reactive Materials. In: Advances in Air Sampling, ACGIH. Chelsea, MI: Lewis Publishers, pp.175-188.

[5] Langhorst M [1983]. A Hollow Fiber Device for Separating Water Vapor from Organic Vapors. Am Ind Hyg Assoc J 44 :592.

[6] Hodgson AT, Binenboym J, German JR [1988]. A Multisorbent Sampler for Volatile Organic Compounds in Indoor Air. In: Advances in Air Sampling, ACGIH. Chelsea, MI: Lewis Publishers, pp. 143-157.

[7] NIOSH [1994]. Formaldehyde on Dust: Method 5700. In: Eller PM, Cassinelli ME, 1/15/98