Document DM9MVk2E7xXVpq0vJVYann28M

Ck*rueai PUT IT IN WRITING Date 7 March 1974 r. To. R. W. McGinnis - Calvert .Subject. From M. H. Btermon - Calvert ( ) Take Action { ) For Your Approval { J For Your Comments . ( ) As Requested CALIBRATION CHECK OF CENTURY ANALYZER._________________________ (X ) For Your Into ( ) Discuss With Me ( ) File (. ) Note & Return In an effort to resolve the background reading on the Century analyzer, a study was made to compare the Century readings to gaa chromatographic readings at different concentrations of VC1 monomer in air. This vaa done by taking a prepared cylinder of air pressurized to 400 lbs./in. and containing 450 ppm of vinyl chloride .-monomer. This cylinder, along with a laboratory air line, mere /-v attached to a mixing cylinder. The sensing probes of the Century analyzer were inserted into the exit tube of the mixing 1 cylinder and the flow rates of the cylinder containing the ^monomer and the air supply were adjusted until the desired reading was obtained on the Century analyzer. At this point, a sample was taken from the exit of the mixing cylinder and analyzed by GC. This result was compared to the reading obtained from the B.F.G. prepared curvewe have been using for the Century -analyzer. Readings were taken at several points between 5 and 100 on the meter. It was found chat by re-drawing the curve through the origin the data obtained from the curve was much closer to the GC data at the lower concentrations.. From the data obtained it appears that a meter readies of 9 la the lowest valid reading ve can report. Any reading leas than 9 should be reported as ^10 ppm of VC1 monomer. The.results obtained are reported 'in Table I-A. Four grab samples of varying concentrations were pulled from the PVC and Emulsion plants and analyzed by both the Century and GC. The results are reported in Table 1-5. The difference between the Century and GC readings is due to the presence of small amounts of VAe and propylene in samples #1 and #2, and VAc and ethylene in samples #3 and #4. The re-drawn curve is attached. HRS:dm Attachments cc; J. T. Barr - V .F. J. D. Kramer G* B. H. Speed H. H. STERM0N AP00040589 TABLE I-A .LAB MIXTURE Century Reading 5 7 9 12 22 51 100 PPM of VCI from Curve 7.5 10.0 13.7 17.5 34.0 80.0 130.0 PPM of VCI by GC 0.0 2.5 12.5 17 .0 35.0 80.0 150.0 SABLE I-B -SLANT SAMPLES .Century Read inA. (a) (b) (c) (d) Sample Sample Sample Sample #1 #2 #3 #4 27 12 51 100 PPM of VCI Proa Curve 44 17.5 80.0 150.0 PPM of Vt by GC 31 9.5 76.0 141.0 (a) (b) <c> (d) ALr lasldc PVC Reactor. Air going Into Reactor. 10 ft. from FVC pump between pump and fan in Emulsion Plant. At exhaust fan in Emulsion Plant. AP00040590 AP00040591 im v im u n r co. X* . t '**71*7* From: Century Systems Corporation F. O. Box 133 Arkansas City, Kansas 67005 Area Code 316 447-3311 Twac. No. 910-740-6740 Attention: V. Mattison Air Sample Collector Tubes - The "FLARE" ARKANSAS CITY, KANSAS - (April 1976) - A new stainless steel reusable sample collector tube from Century Systems Corporation has been designed for use in collection of air samples. The tubes are used In conjunction with a portable air sampling pump. These collector tubes are designed with a sealing flare on one end. The tubes can be provided with a variety of sorbent material; such as: charcoal, Tenax-GC or as fillable blanks. Porous metal end filters are utilised for maximum, mechanical integrity of the tube. Century's "FLARE" tubes are provided in two sixes, a front col lector tube 3" long and a short backup tube 3/4" long. A special sampling and storage tube holder is provided for connecting the two tubes together in tandem and as a means of attaching the sample tubes on the person. The reusable flare tubes are designed to be compatible with the Century Systems' Programmed Thermal Desorber (PTD), and can be dosed, desorbed and redosed many times. AP00040592 From* Century Systems Corporation P. O. Box 133 Arkansas City, Kansas 67005 Area Code 316 447-3311 Twx. No. 910-740-6740 Attention: V. Mattison Programmed Thermal Deeorber ARKANSAS CITY, KANSAS - (April 1976) - A new concept in thermal desorption of air sample collector tubes provides high desorption efficiency, reduces sample degradation and provides means for multiple sample injection into a gas chromatograph. The sorbent material in the collector tube is heated convect&vely with purge gas (air or other) which is drawn through the tube with a mechanism similar to a large 300cc stainless steel syringe. The "syringe" purges the contaminant from the tube, starting immediately after the tube is inserted in an oven. After the desorption cycle the "syringe" retains the contaminant reconcentrated in a fixed volume of purge gas. Analytical sine samples of this gas may then be manually or automatically injected into a GC for analysis. Replicate samples may be withdrawn from, the "syringe" without sample dilution since the syringe piston self-adjusts. Calibration and calculation of time weighted average (TWA) are readily accomplished by factoring the PPM level measured on the GC, by the ratio of the volume of air sampled to the fixed volume (300cc) of the syringe mechanism. AP00040593 AP00040594 AP00040595 AP00040596 V AP00040597 99 a < S?=5 w i is si & S AP00040598