Document 8O7K47KYNGMKXYvJKY75Mw6zB

MANUFACTURING 31V:5 ION KINGSTON NORKS J. Dennis .for communication to C.H- Sub-commit tee) R. K. MeAvon Dr. 3. G. herkman G. N. Mclean J. G. S-ixpscr. G. A. '.vood 3. 3. :vhe K. S. Morrison STUDY NO. 31-19 R. N. Me Maul AIR "3NITCRING STUDY 3j-:9; AS3ESTCS: INSULATORS During the period Ifij Dune I" tc June 1", personal air monitoring <as conducted or. Insulators to assess their daily exposure to asoestos while pert arsing routine maintenance activities. For control purposes, jobs performed by Insulators have been sub divided into four distinct categories, based on the levels and type of asbestos likely to be encountered. These include-. insulation shop activities - canvassing calcium silicate insulation with 'A' cloth (3.6.2.R. job code 73A?) ii) fieldwork - major strip-outs involving the removal of permanent asbestos insulation (3.2.E.R. job code 16*3! (iii) fieldwork - major strlp-outs involving the removal of preformed calcium silicate and thermobestos insulation covered with 'A' cloth ID.c.S.R. job code A67G) Civ) fieldwork - routine daily maintenance. C3.2.2.R. job :ode aS'G' Routine daily maintenance includes such jobs as: )i) installation and removal of non-asbestos insulation (eg. Trymer, fiberglass, etc.) vii) applying and clear..nj mud on calcium silicate insulation ..ill) minor fabrication of calcium silicate insulation in the shop. jiv) minor removal of asbestos bearing insulation on valves. elbows, and snort le.*.;"s of pipes ou? 0909175 DU 028996 SIS3-U.HH:BMSIWiiiwatwtfi itMaiBUjaati .mumaiai; jiiiiii-.: Maintenance activities have not been considered to pose a signifi cant health hazard with respect to airborne asbestos. Currently these jobs are performed without respirators or the use of specia. controls (eg. wetting.enclosures, barriers, etc.). In order to fully characterize eir.plcvee exposure to asbestos, a total of lo per sonal samples were collected, each sample covering the full 8 .-.cur work period. Asbestos Exposure Standards Since small amounts of amcsice asbestos may be encourtered when removing thermobestcs insulation or. valves and elbows, the exposure standard for araosite was used m this study. The exposure limits for amcsite asbestos, as specified under the "Regulation Respecting Asbestos" for Industrial Establishments (Ontario Occupational Health 6 Safety Act, 1978) are as follows: 1. 40 hour time-weighted average (TWA) limit * 0.5 fibres/cc 2. maximum concentration not to be exceeded 2.5 fibres/cc. Sample Collection and Analytical Method (See Appendix I) Survey Results In accordance with Eng. Std. 50LI2, all personal S hour exposure measurements were statistically analyzed using the computer program LOGAN (see Appendix III for LOGAN criteria and results). Personal sample results were as follows: (i) employee daily 8 hour average exposure to airborne asbestos: 0.1 fibres/cc (geometric maar. of 16 samples) (ii) range of measurements: undetected (less than 0.1 fibres/cc) to 0.7 fibres/cc. Summary 1. Employee 8 hour TWA exposure to asbestos was in compliance with the MOL exposure standard. 2. Fifteen out of the sixteen 8 hr. TWA exposures measured, resulted in airborne asbestos concentrations less than or equal to 0.2 f/cc. Based on this evidence, it was concluded that employee 43 hour TWA exposure was also m compliance with the0.5fibres/cc limit. * Note DUP 0909176 The Environmental' Affairs Croup fEAG) will continue to take the conservative approach and time-weight exposures over an 8 hour oeriod. DU 028997 cm.mer.ts i Fecogmacdat tons 1. As required under section 11 (a) of the regulation, the results of t.-.is stucy r.ust re pcstec ir. me Insulation Shop a period of at least 1* cavs . The EAG also recommends that verbal communication of :r.e studv results be ur.certaker. wit.-, all Insulators. 1. ,`ohns Mar.ville '.to. stopped putting asbestos fiber m their mud a few vears ago. However, there still exists on site, significant amounts of old insulation packed with asbestos nud. As the personal results show, cleaning asbestos muc can resu;t m significant exposure to airborne asbestos (see Sample *1, Appendix l'.'.. Based on the results of personal monitoring, the following recomraer.dat ions ire made: i) When insulators are required to ciean old insulation, susoectec :f containing asbestos-bearing mud, respirators are r.ar.catorv. .setting of the insulation should also be. considered. (ii; For all ot.-.er routine daily maintenance activities described at the oeginning of this study, respirators are not aandatorv. 3. The EAG still has to characterice asbestos exposure during major strip-out) involving preformed calcium silicate ar.d t.neraobestos insulation covered with 'A' cioth. This scudv will be undertaker, when the opportunity arises. V.VMcN/ hr Z Z 3C " . OUT 0909177 DU 028998 N APPENDIX I A j BsoTCS :.V a:3: ..ENSL".ATO^S : SAMPLE COLLECTION 3 ANALYTICAL METHOD Sanoii.-.g and analysis was conducted in accordance with the procedures sec out ir. the 'Code for Measuring Airborne Asbestos Fibres'' dates 1132 Duly IS. Sample Collection Ail samples were collected on millipore cellular ester filters '.MAWS 0 3 7 Ao pore site 0.3 micrometers) held in 3 piece 37 mm openfaces filter holders. Air flow was provided bv battery-operated P2S00 Du Pont pumps calibrated at 2.C liters/mm. toi. A soap-film flow meter and electronic scop watch were used to calibrate the1pumps. Ir. general, each sample covered a period of approximately * hours. Che tump was removes from the employee during lunch period only. It was assumed that no exposure to asbestos occurred during the unsampled period: hence 3 hour exposures were calculated by dividing the measured asbestos concentration by 3 hours. Analytical Method All filters including 2 blanks were sent to Ontario Research Foundation to be analysed by phase contrast microscopy. r.n this method, the number of fibres on the filter are determined. Only chose fibres having a length greater than S micrometers and a length to width ratio of 3 to 1 or greater are included in the count. This method does not identify the type of fibre present, all fibres counted were, therefore, assumed'to be asbestos. The Lowest detectable concentration of asbestos fibres was 0.1 f/ce per sample. Both blank filters had undetectable amounts of fibres present. DU? 0909178 DU 028999 DU 029000 : EiiifHr* ^giBiWWWWl^r< mmm* DU 029001 *1 -n i *5 st\ 31 <l ! | > r Iy c fo i it|> ra c il non cu I os l iu lie m sbl oi lii L m. iiiticI to 4) O V) *3 A < DUP 0909131 DU 029002 II. iI1 t e lle r U .l 0 .1 S lni|i: canvabb i iig i ii I c m i s ilic a te in s u la iio n i i i > l u I I i it 1 I he? C| I .is s a m i N o i f a h i lib l ill* 1 * 2*1 b| I m i ii|> M i i i l i i n c b Nfr-ftt8'"-rih BiMiiigggaKgiafiiwiHefiWBifiiigl 11 mu 11 wiimiiiiiMlioiK-*--hi--*-- ^p?Ey3:x r:: A53ESt:S IN AIR; INSULATORS: LOGAN CRITERIA AN3 RESULTS Logar. Criteria As outlined m Engineering Standard SOLIZ, an appropriate objec tive is ts control the contaminant level so that the maximum' probability of emplovee exposure exceeding the exposure limit is 5* To determine if this objective has been met, statistical analysis of the sampling data is required. The computer program LOGA.V provides a complete statistical analysis of air monitoring data. It tests the fit of the data ts a log-normal distribution and then provides important para meters of the distribution. The most important parameter is the acceptance concentration [A value), which is used m the decision process for determining compliance with an exposure limit. The A value is dependent on tr.e number of samples collected and the magnitude of the results. 15 the A value is less than the exposure limit then the control cojective has been met. Other parameters provided by LCGAN are the geometric mean (GM) and geometric standard deviation CGSS) of the distribution. The geometric mean which is the median value, is a good estimate of the employee's average daily exposure to the contaminant being measured. The geometric standard deviation is a measure of the variability in the data; the higher the GSD, the greater the Logan Results CD Cii) (iii) Civ) data followed a log-normal distribution geometric mean of distribution 0.1 fibres/ce geometric standard deviation of distribution 1.9` A value O.i fibres/cc Since A value was less than 0.S fibres/cc, compliance was demonstrated. OUr 0909182 DU 029003