Document g23LGno7Kg6Mkj9VM7RXgXDL

a fEo u it za 55 (-V%4S?) <f24<r*a?*t a. >* la I TC OX0 A,,r3 oa: oa W u ss Uis. * Monitoring Exposures to Vinyl Chloride Vapor Breath Analysis and Continuous Air Sampling EDWARD D. BARETTA,* RICHARD D. STEWART, M.D.,* and JOHN E. MUTCHLERf Department of Environmental Medicine, Marquette School of Medicine, Milwaukee, Wisconsin, and Environmental Health Section, Biochemical Research Laboratory, The Dow Chemical Company, Midland, Michigan ^ An environmental survey was conducted to determine the time-weighted average exposure (TWA) of a group of chemical plant workers to vinyl chloride (VCl) vapor. This survey featured continuous multipoint air sampling and analysis using an infrared spectrophotometer. The inhalation exposure data were digitized and record ed on paper (ape for subsequent computer analysis and derivation of daily TWA values for each worker. A breath sampling program was conducted concurrently with the environmental survey, and a series of breath decay curves relating post exposure breath concentration to vapor exposure were derived from the data. To validate the breath curves derived from on-the-job data, postexposure breath curves were also constructed from breath data obtained following experimental human exposures to carefully controlled concentrations of VCl vapor. The close agreement between postexposure breath concentrations at the corresponding TWA's obtained by each of the methods suggests that either continuous air monitoring or breath analysis is valid for estimating the worker's individual daily exposure to VCl, and provides further evidence that breath analysis is a useful industrial hygiene technique for evaluating vapor exposure. Introduction he question that may arise Tfollowing an environmental survey is whether the chemical vapor concentrations measured are truly representative of the ex posure being experienced by the workmen. Evaluation of the ranges of atmospheric con centration* and estimates of time-weighted average concentration (TWA) are all too often based on a few spot samples obtained under conditions which are not representa tive of all phases of a given operation. A more exact measurement of vapor exposure would have to be based on continuous moni toring of air in the workman's breathing zone during his entire work shift. Obviously this task is made difficult and often impossible ThU paper wai presented at the American Industrial Hyvten* Conference, S(. LouU, Missouri, May 13-17, 1968. 'Marquette School of Medicine, Milwaukee. Wiaconnn. fThe Dow Chemical Company, Midland, Michigan. by the large number and variety of tasks per formed by today's modern chemical plant worker. Recent improvements in automatic moni toring and data processing equipment have provided a means for a more satisfactory so lution. Sequential samplers and automatic analyzers and recorders can now be used to continuously monitor several locations or operations to provide more valid data on which to base estimates of chemical exposure. Computers can be utilized to manage the large volume of data generated by continu ous monitoring.1 Meanwhile a technique has been under de velopment which more precisely defines the level of individual exposure. The realization that the total body burden of a volatile chem ical is directly related to its concentration in expired air led to the development of tech niques for collecting and analyzing breath samples useful in estimating the more indi- 017 UCC 095850 538 Novembn -December, 1969 vidualixed exposure experience of each work man. Studies by Stewart et al. 'J~c have shoun that the excretion or "`decay" of vapor in the breath can be used to characterize the ex posure. Breath decay curves constructed for several chemical solvents have proved clin ically useful as an index to chemical expo sure. These breath decay curves, for the most part, were constructed from postexposure breath data obtained from experimental hu man exposures to carefully controlled and relatively constant vapor concentrations. However, breath decay curves have recently been constructed from breath data collected from workers whose work environment was being continuously monitored.7 In this study of human exposure to vinyl chloride (VC1) vapor, breath decay curves consti ucted from data obtained during ex perimental exposures to the relatively uni form concentration within an exposure cham ber were compared with those derived at the theoretically equal, but broadly fluctuating, concent! ations encountered in a chemical plant atmosphere. A measure of the validity of continuous monitoring data and the use fulness of breath analysis in assessing timeweighted average exposure was reflected by a dose similarity between the two sets of breath decay curves, Procedures Monitoring the Plant Atmosphere The chemical installation surveyed was a closed structure housing several separate chemical processing operations. First, a job survey was conducted for each of four job classifications to determine the work areas frequented by the workmen and the time they spent in each area. For each job classification, five sampling probes were strategically placed in the work area. A sixth probe vvas placed outside the building, and charcoal and silica gel filters were placed in the sampling line to assure a clean air reference. The sample probes were 5/16-inch I.D. Saran tubing through which air samples were drawn by a vacuum pump at a rate of 17.5 liters/min to a centrally located infrared spectrophotom eter. The spectrophotometer was equipped with a 10-meter path-length gas cell sensi tive to 5 ppm of YC1 at a wavelength of 10.63 microns. The YC1 concentration was linearly elated to absorbance up to approx imately 1000 ppm. A schematic diagram of the sampling sys tem is shown in Figuie 1. Sampling was ex ecuted sequentially with a set of six two-wav solenoid valves controlled by a timer which advanced the sampling location every 5 min utes. A visual account of transmittance was lccordcd on a strip chait recorder. Mean while the data weie tecoided in digital form on paper tape by a tape punch and digitizerprogrammed to recoid three equally spaced tiadmittances during the last half of each 5-minute sampling period. The transmittance data furnished In the specirophotometei was converted to absorb ance and ieduced to concentration according t Deri s law : EXPOSURE SUMMARY TfME - WEIGHTED MEAN EXPOSURE 0.0! Wh*f* C, > mon concentration of Station i P, > pr cent of tim spnr at location i during normal work activity Horkt l hi'Mui!u ciuiTram of the infrared i oiUituuuts mtmhnrm" $\ xiom A.,,, (x.-x00) 09,0 (X;--X) heir A Ah A' A', i -- absoibance ba-e-hne response, response at total aiisot ption. -- lesponse at location i. - 2. 3. -1 3. 6 Amt tii an 1 Finally. vv beie K -- C The tap: roughs 55U cal Com pa i toiv. The the mean . trations at woik shift concentrate classificatk obtained fi elsewhere.' during wli eral pieclu use in esta Figure . (fiequcncy classificatii These pio that coni shown. T1 sands of lions and i urc 3 she about by atmospher 7-month p i (inducted ranted ext classificatk the breath On-tln -Jin Three S' weie cond omnenlal boxed poi i ollci ted t on lus an 3 to IU h' tin e reliu n samples w horn short to wlucii threaded i UCC 095851 li rnbir. I9ti'> 'ITC trveved was a era! separate . First, a job h of lout job >e work areas 1 the time they ) classification, gically placed be was placed coal and silica sampling line The sample Saran tubing re drawn by a 17.5 liters/min pectrophotomwas equipped gas cell sensiwavelength of centration was up to approx- sampling sysnpling was ex* of six two-way a timer which n every 5 minlsmittance was order. Meanin digital form t and digitizerequally spaced t half of each nished by the ted to absorbition according <e. 1 absorption, ition i. Xmericnn Industrial Hygiene Assoiiation Journal 530 , Finally. C= KA w here ' A = a proportionality constant 4 C concentration The taped data were processed bv a Bur- ji roughs 5500 computer at The Dow Chemi- | cal Company Computation Reseat eh Labora- i tory. The computer was used to calculate the mean and standard deviation of concen- J trations at each location for each 8-hour j woik shift. Finally, time-weighted average Figure 2. Exposure profiles expressed as VC1 ` concentrations were calculated for each job vapor concentration versus the exposure frequency j classihcation using the time-location data distribution lor the four job t lassifirations. * obtained from the job surveys. As described elsewhere.1 the weighted percentage of time cap glass vial (Figure 4). The overall length * during which concentrations exceeded sev- of the pipet was about 9 inches, so it could j eral prechosen levels was also computed for be conveniently and inconspicuously trans j use in establishing exposure profiles. ported to and from work in a lunch bucket. 5 Figure 2 describes the exposure profiles The plastic caps were lined with six layers i (frequency distributions') for the four job of Saran film identical to that used for the 1 classifications studied during this survey, construction of Saran air sampling bags. A i These profiles show the percentage of time 3/32-inch hole prediilled through one of the | that concentrations exceeded the levels caps provided an access for withdrawing * shown. They summarize several tens of thou- samples. The Saran liners provided an ef | sands of individually measured concentra- fective gas barrier so that vapor losses were * tions and reduce them to single curves. Fig- held to less than 10r/c for a holding period \ tire 3 shows the corrective trend brought of 3 days. j about by actions undertaken to reduce the When collecting a sample the subject was j atmospheric concentration of VC1 over the asked to remove the caps, place the pipet to \ 7-month period during which the study was his lips, and breathe normally in through his ? conducted. Only two job classifications war- nose and exhale through the pipet three * ranted extensive study, but men in all four \ classifications were asked to participate m ^ the breath sampling program. * On-thi'-]ob Breath Sampling | Threeseparate breath sampling programs J were conducted concurrently with the envir| onmental plant survey, designated by the i boxed portions in Figure 3. Each worker * collected three breath samples daily--the first i on his arrival home from work, the second ^ 5 to 10 hours later, and a final sample be4 fore returning to work the following day The I samples were collected in pipets constructed ! from short lengths of 20-mm soft glass tubing !to which had been welded at each end the threaded portion af a 2-dram (8-mD screwif t i i Figure 3. Weekly mean vapor exposure concen trations measured during the survey. Periods dur ing which breath sampling was conducted are rep resented by the boxed-in areas. UcC 095852 540 Novctnber-Deccmber, 1969 Figure 4. Glass pipet (50 ml) used for collect ing breath samples. One cap has a predrilled hole for gas sampling. Both caps have Saran liners which seal the pipet chamber. times. After expelling the fourth breath he quickly caps the tube, trapping a portion of alveolar air. The importance of writing the name, date, exact time of sampling, and the workshift most recently completed, on the label attached to each pipet, was stressed. Aliquots were drawn from the pipets with a 1-ml Hamilton gas-tight syringe and ana lyzed in an Aerograph A-600B gas chromato graph using N- carrier gas and a hydrogen flame detector. Separations were made with a 6-foot, */8-mch I.D. stainless-steel column packed with Carbowax 20M alkaline on Chromosorb W 60/80 mesh acid-washed. Exposure Chamber Operation Three experimental human exposures to VC1 were conducted at nominal vapor con centrations of 50, 250, and 500 ppm. The exposure chamber was a room measuring 41 feet by 6 feet wide by 7,5 feet high. The room had a continuous positive air supply and exhaust system capable of maintaining a slight negative pressure within the cham ber. Continuous distribution of the cham ber air was achieved by recirculating the air with a squirrel cage fan through a series of inlet and outlet ducts spanning the length of the chamber. The VC1 was metered into the duct carrying air exhausted by the squirrel cage fan and entered the room atmosphere via the recirculation system at a rate sufficient to maintain the desired atmospheric concen tration. The vapors were introduced from a pressurized storage cylinder through 6 feet of ' a-inch I 1). stainless-steel tubing into a rotometer prior to entering the circulating air duct. A heating tape wrapped around the stainless-steel tubing presented condensation of the VCl and stabilized the flow of the sapor. The concentration of VCl in the chambet svas constantlv monitored svith a Perhin-El- mer infrared spectrophotometer equipped with a 10-meter path-length gas cell. A sam pling probe, consisting of 5/16-inch I.D. Sa ran tubing, was centrally located during the exposure to represent the breathing zone of all subjects within the chamber. The probe was moved about prior to each exposure to detect imbalance of vapor concentrations within the chamber so that necessary1 cor rections in the recirculating system could be made. Air samples collected periodically within the chamber throughout the exposure day svere analyzed by gas chromatography for added assurance of analytical accuracy. Both the infrared spectrophotometer and the gas chromatograph were calibrated before each experiment and at intervals throughout the exposure day. Each 7.5-hour exposure day included a 0.5-hour lunch period in an uncontaminated area outside the exposure chamber. The TWA concentration was calculated on the basis of 7.5 hours of exposure. Clinical and Laboratory Procedures Each subject had been under careful medi cal surveillance by the medical department for a number of years, and each was given a complete medical examination a few days prior to the VCl exposures. Included were a complete urinalysis and 24-hour urine for urobilinogen, complete blood count with sed imentation rate, reticulocyte count, SGOT, SGPT. LDH, alkaline phosphatase. BUN, creatinine, and bilirubin. Each subject received a repeat physical examination 1 hour before entering the ex posure chamber. This examination included measurement of temperature, blood pressure, and pulse rate, a neurological examination, and collection of blood and breath samples. A questionnaire noting the presence of any symptoms of illness Tor example, headache, nausea, dry throat I completed the pre-ex posure medical evaluation. After the subject entered the chamber, total expired breath samples were collected every hour by having him breathe out through a Saran tube leading to a Saran plastic col lection bag located outside the chamber I idal volume and total expiramiv capacity Amcrit <n were me. in the nh Subjcc measurer chambet 1-hour i ordinatio Tests w< again in gan nun exjmswrt' urine sai pie was SGPT, creatinin Analysis The d ride con. wise mu putn. A Concent1 ed ft om on TWf' sion equ lationshi centra tic and pon Each standard used to , chosen i lidenc c ! servaiicti the statidata am Results E.xpmm A tot:, cxpei itni concent] ducing points. 1 ppm vc i later, Th chloride jeets pri breath s after the and com exposure UCC 095853 cember, 1960 er equipped cell. A saminch I.D. Sad during the thing zone of r. The probe \ exposure to oncentrations tecessary cortem could be periodically the exposure atography for curacy. Both and the gas before each roughout the . included a contaminated amber. The lated on the dures careful medi1 department t was given a a few days rrcluded were our urine for unt with sed>unt, SGOT, iatase, BUN, teat physical cring the extion included ood pressure, examination, eath samples, sence of any le, headache, the pre-ex- he chamber, ere collected e out through n plastic colhe chamber, tory capacity \ i i i American Industrial H'is'icni' Association Journal 541 s* were mcasuied in the morning and again late Table I % in the attemoon exposure periods. Experimental Human Exposure to Vinyl Chloride ( Subjective and neurological responses were Chamber i measured before the subject entered the Concentration i chamber, 15 minutes after entrance, and at (ppm) 1-hour intervals thereafter. Flannagan Co- X S.D. otdination and Crawford Manual Dexterity Tests were conducted at midmorning and again in the afternoon. Breath sampling be 59 261 493 491 8 7 3 Range (ppm) 65- 53 289-243 518471 525-475 TWA* (ppm) 48 248 459 491& S'umber of Subjects 6 4 4 7 gan immediately after the subject left the exposure chamber. A 24-hour postexposure urine sample was collected and a blood sam "Time-weighted average concentration baaed on 7 5 hours area,Including a 0-5-hour lunch period in an uncontammated ^Continuous exposure for 3 5 hours. ple was drawn the following morning for SGPT, LDH, alkaline phosphatase, BUN, Table I shows the analyzed concentration creatinine, and bilirubin determinations. to which the subjects were exposed. Calcu ( Analysis of Breath Data lations of the mean and standard dot iation of exposure concentration are based on chart The decay curves for the breath vinyl chlo readings from the infrared spectrophotometer 6. ride concentrations were constructed by step taken at 5-minute intervals over the two 3.5- wise multiple regression using a digital com hour exposure periods. The TWA is based puter. An empirical relationship of the form on the total 7,5 hours which included a 0.5- Concentration = / (TWA, time) was select hour lunch period in an uncontaminated ed from a choice of several terms, each based area. on TWA and/or time. The resulting regres The final breath decay curves intended for I sion equation best represents the ordered re use as an index to VC1 exposures were ad I lationship between breath vinyl chloride con justed to TWA concentrations of 50. 250, centration, time-weighted average exposures, and postexposure time. Each breath decay curve has an associated standard error of regression which can be used to compute the confidence band for any chosen level of significance. The 95% con fidence hand for the mean of a group of ob servations was chosen in this ease to describe the statistical error associated with the breath data and the regression technique. Results Experimental Breath Curves A total of 13 men participated in the three experimental chamber exposures at nominal concentrations of 50, 250, and 500 ppm pro ducing a total of 160 valid breath data points. Five of the six subjects exposed to 50 ppm were re-exposed at 500 ppm 2 days later. There was no measurable residual vinyl chloride detected on the breaths of the sub jects prior to the second exposure. Serial breath sampling was initiated immediately after the subjects left the exposure chamber and continued up to 20 hours following the exposures. Fioure 5. Breath decay curves based on experi mental human exposures to 50, 250, and 500 ppm of VC1 (7.5-hour TWA). r UCC 095854 542 November-Decembcr, 1969 DAILY VARIATION IN EXPOSURE TO VCL VAPOR (8 hr TWA) COt",C#rbQt>on with confidence bands .only slightly wider than those from controlled human experi ments. The close similarity between these curves and those constructed from controlled exposure data are further illustrated in Fig ure 8. Human Responses Figure 6. three shifts. 0oy$ Of the Month ;> en* nran <;*,< ,, " VCZJ Variation in VGI vapor exposure for and 500 ppm (Figure 5). A 100-ppm decay curve was interpolated from the available data using 1 egression analysis. These curves are presented with the calculated 95% con fidence bands for the mean of a group of ob servations. On-tlu-Job Bicath Curves Ten workmen participated in the on-thejob breath sampling program, producing a total of 91 usable sets of data. Ten percent ol the breath samples collected weie discard ed because of pipet leakage or poor sampling techniques. Absolute breath levels ranged fiom about 20 ppm in one sample taken less than 1 hour after an 8-hour TWA of 250 ppm. to barely detectable levels (<0.05 ppm t in samples taken after exposures at TWA's below 50 ppm. The extremely broad variation in the TWA's experienced by workmen during one of the periods in which breath sampling was being conducted is demonstrated for three shifts of men bearing the job classification "coagulator operator'' (Figure 6). Minute, hourly, and daily fluctuations in the concen tration of a contaminant are most descriptivelv icvcaled b\ continuous monitoring This method of sampling quickly points out the fallatv of judging TWA and peak exposure concentrations on the basis of spot sampling or pn iodic survevs of brief duration I he remarkable correlation between breath concentration and corresponding TWA val ues made it possible to construct the series of breath derav curves shown in Figure 7. From a subjective standpoint no significant untoward affects were noted at any of the exposure concentrations. The only complaints were those of two subjects who reported mild headache and some dryness of their eyes and nose during the 500-ppm exposure experi ments. No odor was detected by anyone entering the exposure chamber at 50 ppm. At 250 ppm all four subjects entering the chamber initially reported that they could detect a very slight odor of the chemical. Five of the seven subjects entering the exposure cham ber at 500 ppm were able to detect the odor of VGI. but after 5 minutes of exposure those five weie unable to detect it even with forced inspiration. Three of the four subjects re entering the chambet after lunch were able F'c.i'RK p Breath decav curves d^riird from brcatli data rnllertcd from workers following onthr-job exposures to VC! vapor ; 8-hour TtVA American to detect could det for apprt the expos The ex ncurologi nificant i ordinatioi ed dm in; Inboratoi' exposure cantlv dii Discussior The o suivev is inant, de late this one is to tration r. ments up on a coni tonductn vms of t rompreht valid lot exposui e On tli* construe t ing conti agieemi'i i h.unber should th od loi a- lhe tl ods shou circumst.' sired, F` mg peak tinuous i tiends ar ulenlilv cquipmci stun res e lems not v uonuteu lw reduv"' IK t t ontn' tieinclv > mt'in rec. UCC 095855 December, 196'J slightly wider human experibetueen these from controlled nitrated in Fig- ? i 1 i * I nt no significant 1 at any of the only complaints 0 reported mild ,f their eyes and xposure expen- anyone entering 1 ppm. At 250 lg the chamber could detect a cal. Five of the exposure charm detect the odor f exposure those ven with forced iur subjects reunch were able l ! * t HOURS CC5 derived from erj following on8-hour TWA). | ! Amrutan Industrial Hvgirnr Association Journal to detect a faint odoi ot YC1 (One subject could detect a taint odor on deep inspiration for approximately 15 minutes alter entering the exposure chamber. The exposure had no noticeable effect on neurological responses, nor did it produce sig nificant changes in the results of mental, co ordination, or manual dexterity tests conduct ed during the exposure period. All clinical laboratory studies performed in the postexposure period were normal and not signifi cantly different from pre-exposure values. 543 Discussion The object of the environmental health survey is to identify the atmospheric contam inant, determine the exposure let el, and re late this to the health hazard it presents. If one is to judge hazard by ambient concen tration measurements, then those measure ments must accurately describe the exposure on a continuing individual basis. A carefully conducted survey combining continuous anal ysis of the work room atmosphere with a comprehensive job study will provide data valid for estimating time-weighted average exposure. On the other hand, breath decay curves constructed from breath data collected dur ing continuous plant monitoring are in close agreement with those obtained from exposure chamber experiments with VC1. These curves should therefore be useful as a second meth od for assessing exposure to VC1 vapor. The choice of whether one or both meth ods should be used depends on prevailing circumstances and on the thoroughness de sired. For example, data useful in describ ing peak exposures are obtained from con tinuous monitoring. Concurrently, exposure trends and concentration gradients may help identify plant operational inefficiencies and equipment malfunctions by revealing specific sources of emission. Correcting these prob lems not only restores a healthful work en vironment but often results in bonus savings by reducing losses of raw material and prod uct. Continuous monitoring, however, is ex tremely costly both in time and in the equip ment required. The scope of data acquired is Figure 8. Comparison of breath decay curves derived from the on-the-job data and the experi mental human exposure data. limited by the number of sampling probes, and these probes are not always capable of accurately measuring the indiv idual's daily exposure experiences, especially should these involve unusual incidences such as chemical spills or exposures outside the monitored area. Breath analysis has the advantage of in dividualizing each worker's integrated daily exposure. Breath decay curves, as an index of exposure, offer a means of estimating the average daily individual exposure on the basis of a few breath samples taken serially in the postexposure period. Consequently breath analysis can be used to diagnose as well as quantitate an exposure which has already occurred. It is a relatively inexpensive and simple method which can be put into opera tion without extensive and costly preliminary preparations. However, postexposure breath analysis does not provide information on the daily fluctua tions of exposure, and the peak exposure con centrations are not made evident bv breath data. Finally, breath analysis is not applica- UCC 095856 544 November-December, 1969 ble to all chemicals, and breath decay curves established for one chemical are not useful as an index of exposure to any other chem ical. The decay curves presented here are in tended to serve as an index of exposure to vinyl chloride vapor and are based on an exposure duration of 7.5 hours for the experi mental exposures, and 8 hours for the on-thejob study. The close agreement between the two sets of curves and the narrow confidence bands obtained in each case demonstrate the usefulness and accuracy of both methods for estimating TWA exposures and indicate the importance of breath analysis and the need for expanding its use in evaluating ex posures to other widely used volatile organic chemicals. References 1. Peterson, J. Em H. R, Hoyle, and E J, Schneider: The Application of Computer Science to Industrial Hy giene. Amer. Ind, Hyg. Assoc. /. 27, 180-165 (March 1966), 2. Stewart, R. D , H. H Gay, D. 5. Erley, C. L. Hake, and A, W. Schaffer. Human Exposure to Tetrachloroethylcne Vapor: Relationship of Expired Air and Blood Concentrations to Exposure and Toxicity. Arch, Emir on. Health 2 516-522 (May 1961). 3. Stewart^ R, D.( H, H. Gay, D. 5- Erley, C L, Hake, and J. fc, Peterson: Observations on the Concentration of Trichloroethylene in Blood and Expired Air follow ing Exposure of Humans. Amer. Ind. Hyg. Assoc. J.23. 167-170 (April 1962), 4. Stewart, R, D., and V K. Rowe: Quinze Ans d'Etudes sur le 1,1,1-TrichIoroethane. Arch. Maladies Profess. 28: 194-201 (1967), * 5. Stewart, R, D., H. C. Dodd, E D, Bajletta, and A. W. Schaffer. Human Exposure to Styrene Vapor. Arch. Environ. Health 16: No 5 (May 1968). 6 Stewart R. D,. E, D. Baretta, H. C Dodd, and T. R Torkelaon: Experimental Human Exposure to Tctrachlorocthyiene. AMA Arch. Environ. Health. (In punt). 7. Stewart, R. D., H. C Dodd, E. D Baretta, A W Schaffer, and J E. Muitihlir: Chronic Overexposure to Benzene Vapor. Presented at the Sixth Annual Meet ing of the Society of Toxicology, March 23-25, 1967, Atlanta, Georgia Received May 26, 1968 Notices and Deadlines It is the policy of the AIHA Journal to accept and publish notices and short items of import and interest to our readers subject to the limitations of available space. This is done as a service to our profession and no fee is charged for such announcements. Some notices are received too late to be carried to advantage in our Jour nal. Persons supplying announcements to us should keep in mind the time schedule of our publication. The Journal appears six times per year with the copies being mailed about the 20th of February. April, June, August. October, and December. While emergency or urgent notices can be inserted up to three or four weeks before the mailing date, such cannot lie assuied. Normally the announcements should be in the Editors hands at least two months or more before the issue in which they should appear. Perhaps these guidelines will aid you announcement generators. UCC 095857 Infrod uc The SAI Public I a colior brous gi were oh five of i that m Mortali: group o of Rent cial Se> studv is the V, mor ta lit facturin tiom of posed t< adpisn'i pared f< expi'sm1 An e ttbss i,!-' M