Document gE0qJkBer4LMxdMKO8GNVLJDJ

FILE NAME Packings and Gaskets PAG DATE 1992 DOC PAG008 DOCUMENT DESCRIPTION Journal Article - Evaluation of Airborne Asbestos Fiber Levels During Removal and Installation of Valve Gaskets and Packing eo oF AM IND HYG ASSOC 531-632 1982 oe . N. Bayone PENGAD PENGAD PLAINTIFF'S EXHIBIT 6028.0 SC EVALUATION OF AIRBORNE ASBESTOS FIBER LEVELS DURING REMOVAL AND INSTALLATION OF VALVE GASKETS AND PACKING William N. McKinnery Jr. Rex W. Moore =_ - Tumkey Environmental Consultants Inc. 500 W. Central Road Mt. Prospect IL 60056-2380 seated Work Practices This project was designed to evaluate airborne asbestos fiber levels genrated during dry installation and removal of asbestos- containing gaskets and packing materials Every effort was made to simulate work practices commonly utilized by pipefit- ters and maintenance personnel in the past when asbestos exposures were not a concern he study was conducted under a set of controlclonedid- T tions All work was conducted in an isolated room constructed in a manner similar to an asbestos abatement project Constru wascctoni duo ctend by an licensed Every effort was made to make these experiments representative of pest work practices involving gasket and packing material instal- lation and removal Work practices were that simulasit muleatd ed those normally used by trained pipefitters when there was little concern about asbestos exposure An experienced pipefitter was on site during all testing to provide consultation and advice on how to perform specific tasks necessary to complete an operation Tools of the trade and other tools normally available to maintenance person- nel performing these tasks were utilized Operations of a similar type were conducted in sequence without cleaning the work area between operations except to maintain a satisfactory work space Each type of operation was asbestos abatement firm BACKGROUND Research Conditions repeated five or more times The gasket removal operations had an average duration of 32 min gasket installation an average duration of 31 min packing removal an average duration of 46 min and packing installation an average duration of 26 min Aslight negative maintained Aslight negative pressure was maintained in the work areafor protecting adjacent areas of the building All personnel entered and exited the work area through a decontamination unit personnel in the work area wore supplied respirators An licensed asbestos worker conducted the removal and installation of the containing materials installawot rk i wasocon n- ducted under the supervision of an experienced union pipefitter The work area was wiped or vacuumed free of debris and dirt following the gasket removal and installation phase and prior to the packing operations Air monitoragigrenssigve conditions with a leaf blower was completed prior to initiation of packing experiments to ensure work area fiber levels were reduced to background values and no contaminatiwooulnd occur between experiments > familiar with asbestos removal work practices Sampling Techniques Materials Researched used air sam- A volume vacuum pump was . via to collect tubing mm to materials were obtained from a scrapyard that bought materials various locations inside the work area Each cassette's flow was and packing materials were obtained directly from distributors measured at the beginning and end of each run with a precision All researched materials were sampled and analyzed by polar- rotameter that was calibrated daily | ized light microscopy PLM for asbestos content by the Chem Corporation which is accredited by the National Voluntary Labo- ratory Accreditation Program NVLAP and by the National Insti- Two to throfete he filter cassettes were positioned on the workelefrt l'apsel for evaluating breathing zone levels to two filter cassettes were positioned within 18 in of the work tute for Occupational Safety and Health's NIOSH's Proficiency Analytical Testing PAT program PLM results showed an asbestos content of 50 to 60 chrysotilein the gasketing materials and 30 to 50 chrysotile in the packing materials being performed Two to four filter cassettes were positioned in the opposite cornofetr he room approximatel4y ft from the work being performed All area samples were collected approximately 5 ft from the floor and 18 in above the worktable used to hold ~~ Copyright 1992 American Industrial Hygiene Association t t 531 531 AM IND HYG ASSOC J. 63 / August 1992 30d 900 06:11 06:11 20-80-2661 TABLE I. Gasket and Valve Packing Removal and Installation Location Personals Center Comers Flow Rates min 0.6-3.6 1.4-2.8 2.0-4.0 __ Volume L 20 70 120 40 80 60 120 the valve that was being evaluated A fibrous aerosol monitor was also used to obtain time informatioonn fiber levels Airflow rates and volumes were adjusted according to the type of work being conducted and the anticipated fiber levels Multiple samples each with a different volume were collected at each location to minimize the impact of filter overloading and underloading Table I lists typical airflow rates and sampling durations associated with these operations All samples were collected on 0.45 cellulose ester filters loaded in mm cassettes with mm nonconductive cowls General LABORATORY ANALYSIS All air samples were analyzed by using phase contrast microscopy PCM by the Chem Corporation which is accred- ited by the American Industrial Hygiene Association AIHA NVLAPfor both transmission electron microscopy TEM and PCM analysis and NIOSH's PAT program All samples were further analyzed by using TEM by the same laboratory TABLIEL PCM and TEM Data for Gaskot Removal and installation PCM Data Fibers Location No. min max Center 23 Center 12 Personal 23 Personal 12 Northeast 13 Northeast 6 Southwest 13 Southwest 6 0.09 0.11 0.05 0.13 0.03 0.13 0.00 0.11 0.59 0.35 0.44 0.29 0.32 0.19 = 0.17 0.16 TEM Data Location Structures min max No. min 28.22 Center 12 Personal 26 Personal 12 Northeast 13 Northeast 6 Southwest 6 Southwest 6 0.86 3.52 0.86 18.45 0.40 74.32 0.69 15.36 0.93 3.23 0.52 12.74 0.91 3.53 AGM - geometric mean GSD geometric geometric CR - removal deviation standard DIN - Installation GMA GSD 0.19 1.62 0.19 0.16 1.91 0.20 0.08 0.16 1.28 1.95 1.16 0.05 4.62 0.14 1.21 GMGM GSD 1.05 1.83 4.58 273 2.97 3.92 1.73 2.74 3.40 3.53 1.56 3.48 1.66 2.00 AM IND HYG ASSOC J. 53 / August 1992 Gasketing Operations PCM analysis of air samples collected during gasket removal and installation showed personal fiber levels ranging from 0.049 to 0.44 fibers for removal and 0.131 to 0.29 fiberfsor installation TEM analysis of air samples collected during gasket removal and installation showed asbestos fiber levels ranging from 0.86 to 18.44 structures for removal and 0.40 to 74.32 structures cc for installation Table II shows specific sample locations and results Packing Materials Operations PCM analysis of air samples collected during packing mate- rials removal and installation showed fiber levels ranging from 0.to01.4 01 rem for o remov val a and 0l .03 to 0.75 fiberfsor installation TEM analysis of air samples collected during packing materials removal and installation showed asbestos fiber levels ranging from 0.39 so 19.57 structures for r^'movaland 0.03 to 10.88 instalfolr a insttai llaotinon Table III shows specific sample locations and results PRELIMINARY CONCLUSIONS Comparison of PCM results with TEM results suggest that under these simulated working conditions airbome asbestos levels reported by TEM analysis are 5 to 10 times higher than those reported by PCM analysis Numerous times PCM levels were observed to be higher than the current permissible exposure limit 0.2 fibers anal datya asnai lyssis is being conducted TEM Data for Packing RemovalInstallation PCM Data Location No. Center 14 Center 12 Personal 21 Personal 18 Northeast 14 Northeast 12 Southwest 14 Southwest 12 Fibers min max_ 0.06 0.60 0.03 0.75 0.05 1.01 0.04 0.52 0.04 0.48 0.03 0.43 0.04 0.34 0.03 0.46 TEM Data GMA 0.25 0,09 0.29 0.10 0.22 0.09 0.19 0.09 GSDB 2.05 273 228 221 1.94 2.48 1.87 2.26 Structures Location No. min Center 7 0.39 Center 6 0.03 Personal 7 0.52 Personal- 6 0.07 GM = geometric mean GSD geometric geometric standard deviation CR .. removal DIN - Installation max 18.88 10.88 19.57 4.05 GM 5.38 0.38 4.37 0.42 GSD 3.49 7.81 3.09 5.80 10d 900 8:11 20-80-2661