Document MGqn8z7p3J0OBk60za57OdnGj

COuTROL METHODS FOR VINYL CHLORIDE IN MONOMER MANUFACTURING AND TANK CAR AND SHIP LOADING Z. Q. Bell, Jr,, J. Lafleur, R. Lynch, and G. Work PPG Industries, Inc. Vinyl chloride is manufactured in 15 plants in the United States TO SERVE THE NATION'S DEMAND ESTIMATED AT 5.6 BILLION POUNDS IN 1974. PPG Industries,; Inc. manufactures vinyl chloride in two facilities. The production of vinyl chloride started at our Lake Charles, Louisiana, PLANT IN 1967; AND THE CARIBE PLANT NEAR PONCE, PUERTO RlCO, STARTED DERATING IN 19^1. PPG DOES NOT CONVERT ANY OF ITS MONOMER TO HOMO POLYMERS OR COPOLYMERS OF VINYL CHLORIDE. In view of;health hazards that have been defined as arising from THE TOXICOLOGICAL EFFECTS OF VINYL CHLORIDE, PPG WOULD LIKE TO DESCRIBE FOR POSSIBLE USE BY OTHERS TWO PROCEDURES FOR HANDLING VINYL CHLORIDE CONTRIBUTING TO IMPROVED VINYL CHLORIDE CONFINEMENT AND PERSONNEL EXPOSURE CONTROL. The FIRST OE THESE PROCEDURES INVOLVES SAMPLE COLLECTION AND ANALYSES. In our process, (Duality control sample collection is achieved from DIFFERENT POINTS:IN THE SYSTEM BY ATTACHING THE SAMPLE BOMB TO A SMALL FITTING IN A CLOSED LOOP SYSTEM (SLIDES 1, 2 AND 3). The SAMPLE BOMB IS INSTALLED VERTICALLY IN THE SYSTEM WITH ITS STAND LEG FITTING IN THE WC 000020417 2- - top position. This prevents overfilling and bomb overpressurization. To ASSURE THAT THE BOMB IS INSERTED PROPERLY, THE BOMB FITTINGS ARE OF DIFFERENT SIZES. THE SAMPLE COLLECTION LINES ARE SMALL DIAMETER STAINLESS STEEL TUBING. VALVES ARE LOCATED AS CLOSE AS POSSIBLE TO THE SAMPLE BOMB !CONNECTIONS TO MINIMIZE THE QUANTITY OF VINYL CHLORIDE THAT WOULD BE VENTED, THE SMALL AMOUNT OF VINYL CHLORIDE TRAPPED BETWEEN THE VALVES IS RELEASED TO A REMOTE LOCATION AND THE TUBING BETWEEN THE VALVES IS THEN PURGED WITH NITROGEN. The STORAGE OF SAMPLE BOMBS WITHIN THE MAIN OR PLANT LABORATORIES IS PROHIBITED, AND ALTHOUGH THESE SAMPLE BOMBS WERE CAPPED BETWEEN USE, STORAGE RACK ON CABINET IS PROVIDED, AS SHOWN IN SLIDES 4. ALL VINYL CHLORIDE BOMBS MUST BE STORED IN THESE CABINETS WHILE NOT IN USE, AND ALL ANALYSESl OF SAMPLES MUST BE ACCOMPLISHED WITHIN A LABORATORY 6), Ahood (Slide flexible line is installed on the gas chromatograph DISCHARGE THAT DIRECTS THE PURGE FROM THE GAS CHROMATOGRAPH BACK INTO THE LABORATORY HOOD (SLIDE 6), After the analysis, there is from 600 to 700 ml. of vinyl chloride REMAINING IN THE BOMB. THE SAMPLE BOMBS ARE CAPPED AND RETURNED TO THE PLANT WHERE THE 80MB AND ITS RESIDUAL CONTENTS ARE INSERTED DURING THE NEXT SAMPLE COLLECTION ROUND. THIS PROCEDURE RETURNS THE UNUSED VINYL CHLORIDE TO THE PROCESS. THE BOMB VALVE INTEGRITY IS CHECKED PERIODIC AllALLY using a Century organic vapor analyzer. laboratory hoods :re vinyl chloride IS used OR analyzed HAVE BEEN CHECKED FOR ADEQUATE ACAPTURE VELOCITY. BAFFLE HAS BEEN INSTALLED ACROSS THE FRONT LIP OF 00020A1B VVC 0 -3- THE HOOD TO PREVENT ANY VINYL CHLORIDE VAPORS/ WHICH ARE HEAVIER THAN AIR, FROM EXITING THE HOOD (SLIDE 7). THE LEVELS OF VINYL CHLORIDE ARE ROUTINELY MONITORED. The second procedure to be presented involves the loading of vinyl CHLORIDE INTO t|nK TRUCKS/ TANK CARS/ BARGES/ OR SHIPS. THE OXYGEN CONTENT OF EMPTY TRANSPORTATION VEHICLES IS DETERMINED PRIOR TO LOADING. IThe oxygen analyzer is 'vented remotely (Slide 8). n tank car and tank TRUCK LOADING/ THERE ARE EQUALIZING LINES FOR THE DISPLACEMENT OF THE VEHICLE VAPOR CONTENT. THE VAPOR SPACE MATERIAL IS EQUALIZED WITH THE STORAGE TANK FROM WHICH THE VEHICLE IS BEING LOADED (SLIDES 9 AND 10). There are a number of ways to determine when a tank car or tank truck FULL. The vinyl chloride may be scale LOADED or a flow meter may be USED. A MAGNETIC LEVEL INDICATOR IS USED by SOME PRODUCERS. MANY MANUFACTURERS USE A GAUGE ROD TO DETERMINE WHEN A TANK CAR IS FULL/ AND THIS IS A POTENTIAL EXPOSURE SOURCE UNLESS SPECIAL PRECAUTIONS ARE TAKEN. Exposure may be prevented by the use of a quick disconnect hose for the TANK CAR GAUGE ROD. A BULL'S EYE IS PROVIDED ON THE HOSE OUTLET FOR DETERMINING WHEN THE TANK CAR IS FULL (SLIDE 11 AND 12). THIS BULL'S EYE ARRANGEMENT IS ONLY NEEDED WHEN AN OPEN GAUGING DEVICE IS IN USE. The FINAL PROBLEM FOR TANK CAR OR TANK TRUCK LOADING IS THE CLEARING OF THE LOADING HOSjE AND SPOOL PIECE SO THAT THE HOSE MAY BE DISCONNECTED WITHOUT ALLOWING EXPOSURE. The LIQUID IN THE LOADING HOSE IS PUSHED (WITH NITROGEN) INTO THE TANK'CAR (SLIDE 13). THE LOADING LINE IS THEN Nl.ROGEN PURGED FOR REMOVAL OF VINYL CHLORIDE VAPORS BEFORE THE LOADING VVC 000020419 HOSE IS DISCONNECTED (SLIDE IN). In TANK TRUCK LOADING OPERATIONS, THE LIQUID IN THE SPOOL PIECE RETURNS TO THE ACCUMULATOR THROUGH A SPRING- ALOADED CHECK VALVE, NITROGEN PURGE IS USED TO DISPLACE ALL OF THE VINYL CHLORIDE VAPORS FROM THE SPOOL PIECE TO THE ACCUMULATOR. The loading of ships nnd barges involves most of the same confine ment PROBLEMS AS TANK CAR AND TANK TRUCK LOADING. The LOADING OF SHIPS OR BARGES WITH HIGH INERTS PRESENT CAUSES SIGNIFICANT PROBLEMS WHEN THE VAPOR SPACE IS EQUALIZED BACK TO THE STORAGE TANK. A SOLUTION TO THIS PROBLEM HAS BEEN THE INSTALLATION OF AN EQUALIZER LINE CONNECTING THE DOCK SIDE SPHERE VAPOR SPACE WITH THE STORAGE TANKS IN THE PROCESS AREA. A COMPRESSOR HAS BEEN INSTALLED TO RETURN THE CONTENTS OF THE SPHERE .APOR SPACES TO THE PROCESS. THE VINYL CHLORIDE IS RECOVERED IN THE PROCESS AND THE INERTS LEAVE WITH THE BYPRODUCT HCl STREAM. THEREFORE, THE INERTS FROM SHIPS OR BARGES DO NOT CAUSE VINYL CHLORIDE TO BE VENTED. There are some routine equipment clearing procedures that are FOLLOWED SO THAT - OPERATOR EXPOSURE TO VINYL CHLORIDE IS WITHIN THE OSHAPROPOSED STANDARD. SLIDES 15 AND 16 SHOW A SYSTEM THAT HAS BEEN INSTALLED THAT WILL PREVENT EXPOSURES WHEN IT IS NECESSARY TO CHANGE VINYL CHLORIDE POLISHING FILTER ELEMENTS. PUMPS THAT NEED REPAIRS MUST BE CLEARED OF VINYL CHLORIDE. SLIDES 17 AND 18 SHOW THE METHOD USED IN CLEARING PUMPS. The VENT PURGE STREAMS FROM CLEARING EQUIPMENT CAN BE SENT TO THE INCINERATORS OR COMPRESSED AND RETURNED TO THE PROCESS. VVC 000020420 - 5- In the foregoing, examples of operating modifications that are APPLICABLE AND PRACTICAL IN MINIMIZING EXPOSURES HAVE BEEN PRESENTED, It IS OUR OPINION THAT SOME OF THESE MAY BE HELPFUL TO OTHERS. * VVC 000020421 Smde no. 1 2 j 4 5 B 7 8 y 10 11 12 13 14 15 16 17 18 LIST OF SLIDES Description Sample Bomb Sample Point Figure Actual Sample Point Inside View of Bomb Cabinet Analyzing Samples * Gas Chromatograph Lad Hood Oxygen Analyzer Figure of Loading Operation Picture of Equalizer Manifold Gauge Rod Connection Eull's Eye Pushing Liquid Out of Loading Hose Nitrogen Purging Loading Hose Figure of Filter Picture of Filter Figure of Pump Picture of Pump VVC 000020A22 M. E. Sulhe rland and R. K. Wheeler, Jr, Union Carbide Corporation, South Charleston, West Virginia Control of vinyl chloride emissions irt vinyl chlo ride monomer transportation operations is a difii< iiJt problem. The primary control objective is to protect the health of employees and the general pub lic from d?mage h y !c>:cc as j ve vinyl chloride expo sure. With this objective in mind, the Occupational Safely and Health Administration has issued a stan dard for workers. This standard will be followed by regulations from the Environmental Protection Ad min ist rat ion, die Department of Transportation, and tlie Coast Guard. The OS1 IA permissible exposure limits of cute part per million by volume for workers ami the rumored E PA limit of 90 parts per billion by volume for plant fence-line concentration are hard U> conceive in an industrial environment. Gauging a lank car wiLh a slip lube releases several pounds of vinyl chloride to the atmosphere. One pound of vinyl chloride raises the concentration of 6 MMCF of air to one part per million or 70 MMCl-' of air to 90 parts per billion. While the subjects of safe vinyl chloride concentration and the health problem resulting from vinyl chloride exposure may be de batable, governmental regulations in regard to worker and public exposure are here to stay. There are nu easy solutions to emission control; thus, the scope ol' lii i s discussion is limited to a brief review of vinyl chloride t runs po rial ion operations, defining some major problems, and proposing some wavs of approaching ifie .'iolulinn to those problems. Vinyl chloride distribution facilities generally consist of large storage tanks such as refrigerated spheres or buried tanks located at some distance from the production facility, smaller horizontal storage vessels located in or adjacent to die produc tion facility, pipelines, shipping containers, and shipping container loading or unloading facilities. Some vinyl chloride monomer is moved by tanker, by truck, and by barge but, in the main, vinyl chlo ride is transferred from producer to user via tank cars or pipelines. Figure 1 shows a flow sheet of a representative vinyl chloride distribution system. The VCM pro ducer transfers the product from plant to a storage sphere from which tank cars, trucks, or ships are loaded. The shipping containers and the storage tanks are pressured by the vapor pressure of vinyl chloride contained. Theoretically-, a tank car con taining only vinyl chloride gas can be loaded without venting. On a more practical basis, these contain ers are vented either to the air or back to the stor age tank from which ultimately sonic inert gases must be released. The loaded tank car is then valved in, loading hoses are removed, and the car is moved via the railroad to the consumer. At the consumer, unloading hoses arc attached, pressure in the car is raised above that generated by ambient temperature with vapors from a vinyl chloride va porizer, and the cur contents are pumped to a stor age lank. At the end of the unloading operation, the V n l Camp re s so r i >foce n s FIGURE I VINY L CHLORIDE DISTRIBUTION SYSTEM ressuro in the car isi reduced by a compressor to to 5-lb. gauge. The car is valvcd in and the hoses removed. The consumer's system is also pressured by the vAp-or pressure of vinyl chloride, but again nome ventirxj; of inert gases is required. For nor ma] iliMnluttuvn operations, major omissions result from slip-iubo gauging of the lank car, removal of loading and vent hoses, and any venting required to niainUm (he storage tank pressures at the pressure of saturated vinyl chloride vapor. Vapor compres sion and condensation arc often used for tank cool ing. The presence of large amounts of uncoudensable gases would preclude, the operation, of such a cooling system. The plant usually has a remote vent stack or a flare Jor handling these vents. Formerly, when equipment maintenance was re quired, the item was emptied of liquid vinyl chlo ride if possible, the pressure released to a vent system or to the air, and the equipment purged with mertgas to remove the contained vinyl chloride gas. The inert, gas was then removed by a thorough airing of the equipment. On completion of the maintenance work, the equipment was purged with inert gas fol lowed by displacement of the inert gas with vinyl chloride. Gases released were vented to a flare slack or simply released to the ambient air. Main tenance work on a tank car could result in release of 500 pounds of VCM while a simple pump repair ght release 1 to 10 pounds. Design of storage ..j'lUeiriH often stressed vapor conservation for oper ational emissions, but only rarely was provision made to control emissions resulting from mainte nance work. The various governmental safety regulations will require changes in distribution equipment and oper ations to control vinyl chloride monomer emissions. Reducing emissions "to achieve Lhe permissible levelo of exposure required is arduous, expensive, and time-consuming. A thorough detailed discussion would require more time than is available; there fore, only certain useful items will be covered. Gauging devices that permit no product emission must be installed on tank cars, tank trucks, and barge tanks. A common past practice in loading a shipping vessel was to pull the slip tube out to the desired liquid level and open the valve slightly. When the vessel was filled to the desired level, the spurting of liquid was readily visible to the loader from a distance, and loading was terminated. This procedure also took care of any air or other non condensable gases that might be in the car. As a result of the OSHA regulation, various ventilation hoods and sight-flow indicators are being used in loading and unloading operations. A gauging device that has worked well on tank cars is a float that is magnetically coupled to a tape system in a pipe iso lated from the product. In the event of a failure of the mechanical tape system, it can be removed for repair without emptying the car. The tape .sightglass simply protects die tape assembly from the weather. The tank can be gauged by reading the tape and measuring the tank temperature. Adapta tion of this or similar devices to all shipping con tainers is die most direct approach to control of gauging emissions. Tank car size is being limited to 25, 500 gallons for all new cars in vinyl chloride service. The car must either be insulated or have steel safety shields WC 000020474 on tii; ends of the c-ir to reduce the possibility of tank punctures in derailments. Cars that are not in sulated or do not have the safety shield must be switched individually by engine in the rail yards. Major industry use of a poorly-de signed, 38,000gallon tank car for vinyl chloride transport has caused much of the railroad transportation hazard and the resulting regulations. These cars with their six-wheel trucks were unable to round a normal railroad curve properly. As a result, they derailed frequently, especially when empty. The couplings often did not match properly with other cars in switching; thus, in switching and train make-up, the coupler missed connection and the tank car was punctured when it struck the car being coupled, limitations on car size and handling procedures are highly regressive steps and fail to directly approach .the .problems of proper tank car design and of fail ure by the railroads to maintain their road beds. For an industry changing to 30, 000-gallon reactors, the proper tank car for minimum emissions is the 48,000-gallon tank car equipped with float gauging and insulation. In .requiring the small tank car, the Department of Transportation has reduced some of the danger of tho individual accident at the risk of increasing the cost of transportation and of increas ing the frequency of accidents by requiring more tank cars for vinyl chloride transportation. Pipe lures offer tire ultimate potential reduction in emissions for VCM distribution, but pipelines car rying suspected carcinogens will be subject to a new set of rules. Above-ground pipelines can bo proper ly labeled and monitored regularly for leaks. Emer gency procedures could be instituted quickly before any leak became significant. Buried pipelines will require above -ground warning signs, a foolproof system for leak monitoring, and cathodic protection. The only foolproof' system for leak monitoring in a buried pipeline appears to be a pipeline within a pipeline. The oufside pipeline would provide the basis for leak detection and disposition. In either the above-ground or buried pipeline, the number of flanges, valves, and pumps should be minimized while provisions for prompt isolation of leaking sec tions and disposition of their contents must be planned with great care. In-plant pipelines impose little or no regulatory problems, but the likelihood of getting a permit to install a vinyl chloride pipe line on public property appears remote. Vinyl chloride scavenging systems will need to be installed or expanded so that each pipeline, heat exchanger, pump, tank, or tank car can be stripped of vinyl chloride liquid or vapor in the event of fail ure, prior to maintenance work, or prior to routine disassembly. Figure 2 shows a flow sheet of such a system. Where there is access to a plant monomer recovery system, an additional compressor, a con denser, and a collection tank are not needed. In re mote facilities, this scavenging system could con sist of a small compressor, such as the Corken built by Pump Service Company. This compressor requires 30 horsepower and will pump 40 to 54 ACFM from 0 to 105 pounds without lubrication. If the compressor discharge system has the ability to absorb heat, then the condenser is unnecessary. This compressor has been used to evacuate unload ing hoses, tank cars, and other equipment at a tankcar unloading station. The compressor maybe dis charged into the liquid vinyl chloride transfer pipe line without cooling if the system has adequate heat dissipation capacity. In an emergency, it has been simply discharged into an empty tank car. When such a scavenging compressor is used intermittent ly, provision must be made to keep it from filling up with liquid vinyl chloride. On this installation, electric heaters were installed in the compressor suction trap to vaporize any liquid that collected during the out-of-service Lime. Activation of the heaters for a preset time i3 required before the compressor will start. The scavenging system must be designed to fit the operation involved. The moat important criteria to consider in such a design is to be sure all eventualities requiring scavenging have been considered, and to be sure that air is ex cluded from such a system. vi m : r IGU JLt_ _l______VJ.VTl. UU.OK1PC SCAVStK.IHC SYS ITM 3 icif k i: j ><~n,vf.n r vfnt scauv hin : v> * i km 000020^ Nj'jC. hie rt cas ini ct> i jig of equipment that has been .scavenged of its available vinyl chloride monomer is necessary to reduce the explosion hazard and to remove the last traces of vinyl chloride monomer. A tank-car unloading hose that has been scavenged contains several tenths of a pound of vinyl chloride. A lank car contains several hundred pounds. This material has to be removed and the VCM concentra tion in the equipment reduced. One lank-oar shop h a r. al ready notified owners it will nol aicopt tank < a r fj for servicing containing more than l\5 ppm VCM . Depending on the equipment conl'iguration, it may be swept out by blowing inert gas through the system or it may he diluted by alternately pressur ising the tank with inert gas and venting it down. In any case, sweeping the last traces d! vinyl chloride out of equipment prior to maintenance generates a largo volume of inert gas contaminated with vinyl chloride. A rule of thumb for the pressurizing and venting technique its 15 to 20 cubic feet of inert gas per cubic foot of vessel capacity. The inert ga3 must then be removed by airing' if vessel entry is required. When maintenance work is complete, the process must be reversed with inert gas purging out the air and then vinyl chloride purging out the inert gasefl. Maintenance of distribution facilities and t rans portation equipment will require a supply of inert gas and the equipment to dispose of the VCM contaminated inert gas. Refrigerated sqlvcnt scrubbing of inert gas stroams, as shown in Figure 3, represents the most reliable and economical means of removing vinyl chloride from inert gas. The choice of solvent is largely a matter of which ones are readily available, the conditions ehbson for stripping the dissolved vinyl chlorldo from the rich solvent, and limiting the loss of solvent; with the vent gas stream. Sol vents that have been used successfully are acetone, methyl ethyl keton$, ethylene dichloride, butyl ace tate, and hcptyl butyl ketone. Absorber tempera tures of 0 to -20^C are effective. To keep equip ment sizes down, a solvent scrubber is normally operated under pressure in conjunction with the vinyl chloride scavenging system. Vinyl chloride recovery efficiencies of 99. 5% are readily obtained. Solvent rates of A pounds per pound of gas at 100 poig and 10C yield essentially vinyl-chloride-free vent gas. Refrigerated vpjnt coolers are useful only where the volume of inerts is very low or more efficient recovery equipment is not available. Figure 4 shows an inert gas purge system that operates in conjunc tion with a large refrigeration system to rid a stor age sphere of inert gases. This unit requires two horsepower to cool inert gases to -29eC and dis charge heat at 6*C<. The inert ga3 discharged to the air contains 13 Vo VCM by volume. The storage upbore u9ing this unit 13 remote from other operalicjis and receives little or no operating supervision. Jn this case, the amount of vent gas is essentially insignificant and, due to remoteness, no personnel exposure is involved; thus, a relatively poor system in acceptable. Decontamination of vent gases by other methods. 4 V*. M rl PEFUKiERATED VENT SYSTEM such as carbon adsorption or incineration followed by scrubbing the incinerated gas with water, arc be ing considered by many companies. In the case of carbon adsorption, the technology is not fully de fined and proven in practice. Operation of the ad sorbers is cyclic, requiring more operating labor; the formation of polymer and peroxides on the car bon could be problems, Incineration or flare stacks arc widely used for disposal of flammables, and should be used as a final cleanup technique for even solvent-scrubbed vent gases. Use of incineration to dispose of relatively large amounts of vinyl chlor ide would entail removal of the hydrogen chloride generated by water scrubbing and subsequent dis posal nf acid formed. Disposal of quantities of salt, muratio acid, or hydrogen chloride is a pollution problem not lightly considered by EPA, Monitoring of vinyl chloride concentrations in distribution operations is necessary to determine sources of emissions and to protect personnel and the public from excessive exposure to vinyl chloride in their breathing air. For general troubleshooting and survey work, one of the most adaptable instru ments is the Century Organic Vapor Analyzer wilii or without the chromatographic column attachment. This instrument is portable and is direct reading in terms of organic vapor. If there is a question as to whether the organic vapor is vinyl chloride, then tlf chromatographic column attachment has value. In addition to locating leaking pump seals, valves, and other fixed equipment, it should be used to carefully check each loaded tank car or other shipping con tainer for leakage prior to shipment. Admittedly, a shipping container can develop a leak in transit but, in most cases, the containe r was leaking when shipped since this was the last time the container's mechanical equipment was operated. For large, fixed distribution facilities, a fixed area monitor with alarms, such as the multipoint automatic chro matograph, is valuable. Fixed distribution facili ties are usually remote from plant operations and may not even be manned full time. This lack of supervision plus the potential for massive VCM re leases makes automatic detection a primary protec tive device. The pictured automatic chromatograph VVC 000020426 &SXV.' Manual VCM monitoring y/ilh a portable organic vapor dc Uj cto r Automatic chromatograph for fixed installation VCM monitoring analyzes 19 points wiiJIiin a remote vinyl chloride tank-car unloading and storage system every 40 minutes, and will souhd an alarm if a preset con centration is exceeded. Automatic analysers, un fortunately, provide more data than can be readily a s simulated by the operating supervisor; therefore, a data processing system is worthwhile. These sys tems compile and correlate results so that problems, other then emergencies, can be. identified. Regardless of the technique or the equipment for monitoring, it should be done frequently and thor oughly. The monitoring data should be carefully evaluator! and kept on file for up to 30 years, if per sonnel exposure is involved. If the evaluation iden tifies a problem, Lhcn prompt action must be taken. Monitoring provides the basis for demonstrating compliance to govc mnjiental regulations and, as such, is required. In addition, it is the means by which equipment is improved, faulty work practices arc corrected, emergency situations are controlled, oblcrns arc identified ' a n d, above all, personnel c protected from excessive exposure to vinyl chloride. Monitoring i's the means one uses to see the situation and, as such., it is the most important action tn be taken in the r-nrrol of vinyl chloride omissions. Timely data from monitoring, though expensive in terms of equipment, is less costly than using yesterday's data on today's problems. 5 Automat ion is the imal approach to control 01 personnel exposure to vinyl chloride. Regardless of the system design, the potential for personnel ex posure to vinyl chloride exists; thus, removal of personnel from that operation via automation re duces hazards as well as cost, Vinyl chloride stor age lank areas may be barricaded and never entered in normal operations. Tank-car unloading or load ing can be designed so that the only human interven tion is the unloading hose coupling or uncoupling. Equipment for these kinds of operations arc valves with pos ition indicato rs , pipeline flow indicators, remote-ope rated pumps, remote'control valves, and programmed controllers. The pictured vinyl chlo ride sphere with attendant pumps, reirige ratron equipment, and pipelines is operated entirely by re mote control from a central control room. The tank car unloading system ream res manual hookup and disconnections of the unloading hoses and operation of tlie shutoff valves on the car and at the hose ends. All odier operations are controlled from a control building. 'lhc foregoing discussion in intended to show some of the ways to reduce vinyl chloride emissions and control personnel exposure to V(~M :n distribution operations. No implications of governmental ap proval for tlie techniq ics involved should be drawn. While the various pimedures will lend u> m in ; mu :r VCM storage sphere equipped with remote-controlled valve h and pumps exposure to vinyl chloride, the ability to meet the various regulations is not implied through use of the same- In controlling vinyl chloride emissions ami reducing personnel exposures, interaction of regu lations and goals from OSHA, EPA, DOT, and the Coast Guard must be considered; i. e. , ventilation of the work space may please OSHA while creating EPA problems. The only sure thing concerning vinyl chloride regulations is that they are here to stay and the latitude available to the vinyl chloride monomer and polymer industry, with regard to em ployee safety and to plant procedures, will be mini mal. Pictures were made available by Union Carbide Corporation. The authors M. E. Sutherland joined Union Carbide Corpora tion in 1942 upon receiving his B.S. Ch.E. Degree from West Virginia University. He has spent most of his career in the production of vinyl chloride mon omer and resins and has held a number of supervi sory positions in these operations. Since 1969 he has been associated with the Chemicals and Plastics Safety Group and presently holds the position 01 Process Safety Program Manager. R. N. Wheeler, Jr. , Assistant Production Man ager for Vinyl Resins at Union Carbide Corporation, is a graduate chemical engineer from Virginia Poly technic Institute. Mr. Wheeler has been associated with vinyl resins manufacture for thirty years and has represented Union Carbide Corporation in vari ous aspects of the vinyl chloride health problem. VVC 000020428 6