Booth cleanup is accomplished by wetting a rag with methylene chloride and wiping the area to be cleaned.

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2 CASE STUDY #3 - Paint Gun Cleaning / Paint Cleanup Problem Summary; The Georgia Shelf Company operates a paint booth, which applies urethane, latex, and enamel coatings to industrial and consumer furniture. The shelves are made of wood and metal, and shipped into Georgia Shelf from an outside fabricator. Paint guns are routinely cleaned with methylene chloride or methyl ethyl ketone (MEK) blends. Paint lines are purged in between color changes with methylene chloride or MEK The paint booth and surrounding area is also cleaned with methylene chloride. Other solvents have been tested, some even implemented, but the painters return to methylene chloride and methyl ethyl ketone for ease of use and rapid evaporation. Existing Equipment; The primary equipment modernization focus has been on the application equipment. The paint booth has been modernized with filters and HVLP spray guns. No gun cleaning equipment has been purchased to date. Guns are still cleaned by immersing them in a bucket of solvent for 15 to 30 minutes. The Process; At the end of every shift, paint guns are disconnected from paint lines, and immersed in a 5 gallon bucket containing methylene chloride or MEK After soaking for a few minutes, the operator will remove the gun and remove any remaining paint patches with a screwdriver or a rag. Then the guns are placed back in the bucket for a final few minutes of soaking. Paint lines are purged between color changes with methylene chloride or MEK blends. The paint input line is placed in a 5 gallon bucket of clean solvent. The pump is then turned on and methylene chloride or MEK is pulled into and through the lines, discharging into a catch bucket at the gun end of the line. Booth cleanup is accomplished by wetting a rag with methylene chloride and wiping the area to be cleaned. Produced by EOEML of the Georgia Tech Research Institute and the Pollution Prevention Assistance Division of the Georgia Department of Natural Rcsoum~

3 3 CASE STUDY #3 - Paint Gun Cleaning / Paint Cleanup, continued Workforce Considerations: The workers in the paint area are aware that they are using hazardous solvents. They wear gloves whenever possible. Since the culture at Georgia Shelf does not promote pollution prevention or solvent awareness, most of the workforce is not overly sensitive to the issues surrounding their continued use of hazardous solvents. The consensus on the shop floor is that the methylene chloride and MEK work well and cause no undue problems. Therefore, the workers are content to keep using it, until instructed to do otherwise. Produced by EOEML of the Georgia Tech Research Institute and the Pollution Prevention Assistance Division of the Georgia Department of Natural Resources

4 DuPont Case Study #3 PROPOSAL FOR CASE STUDY #3 - Paint Gun Cleaning Key Customer Need: The customer does not perceive much need to change so any proposed alternative will encounter resistance. However, the use of MeCl and MEK present potential worker exposure, flammability and regulatory problems that the company should not ignore. Proposed Cleaning; Agent: Dibasic Esters (DBE) are aggressive solvents designed for removal of paints and epoxy resins. They have high flash points which means they are less of a flammability hazard and lower evaporation losses compared to traditional, volatile solvents. Proposed Process: The process remains the same, except the DBE will not dry as quickly and many have to be towel dried or blown off parts with compressed air. Equipment Required: No additional or different equipment needed. Environmental Aspects: Air emissions would be greatly reduced, however, the company will have increased drum waste quantities since the DBE will not disappear from open drums. Disposal costs would be reasonable since the waste will probably be classified as non hazardous. Benefits to Customer: The proposed alternative would remove many potential negative impacts on the company, from worker safety, fire hazards and EPA fines. Insurance premiums may be reduced.

5 ISP Engineered Products Case Study #3-Page 1 Response to Case Study #3 GEORGIA SHELF COMPANY - PAINT GUN CLEANING / PAINT CLEANUP Project Overview Cleaning paint guns and paint related equipment results in the release of large amounts of chlorinated and hazardous solvent to the atmosphere. Our research shows that larger industries have altered their painting processes in ways that enable them to begin moving away from hazardous solvents, (i.e.; switching to powder coating techniques), but small and medium sized business do not have the resources to make these changes. As a result they still rely on traditional painting and solvent cleaning methods. We will demonstrate that an alternative, non-volatile solvent called SAFE STRIP, manufactured with N-Methyl Pyrrolidone, may be used for cleaning paint guns, lines, etc. without the introduction of significant chemical hazards. N-Methyl Pyrrolidone chemistry is used in other facets of industry and has a documented history of positive safety and toxicology. Its applicability as a base ingredient for a paint cleanup solvent alternative is well documented. SAFE STRIP environmentally preferred solvent may be used in existing equipment, with little or no modification. The Georgia Shelf Company will incur no upfront capital expense to make this switch. Paint Cleanup, A Brief History Thousands of small and medium sized business apply industrial paint and coatings during their daily operations. Paint clean-up waste is one of the most pervasive hazardous waste streams generated by industry. Four of the seventeen chemicals listed in EPA s 33/50 source reduction program are found in paint cleanup solvents: methylene chloride, methyl ethyl ketone, trichloroethylene and 1,1,l trichloroethane. As regulations governing air emissions become more stringent, manufacturers who use any type of paint or coating are rethinking their process with an eye towards reduced emissions. The area of primary concentration has been the spray-booth itself Various technologies, including water screens and mechanical filters, have allowed industrial users to minimize fugitive paint emissions during spraying. Cleaning the tools used to apply paint has received less attention, as the traditional solvents used for this cleaning have only recently fallen under strict regulatory control. Paint application tools require frequent cleaning to insure smooth transmission of the paint or coating being applied. Paint guns and other air driven paint application tools are attached to flexible hoses which draw the paint to the point of compression. Gun and line cleaning is required when the paint type or color is changed and between shifts to prevent material buildup. - continued - PO Box 1622 Tucker, GA /

6 ISP Engineered Products Case Study #3-Page 3 After we have answers to these three key questions, we can begin field testing the SAFE STRIP, in much the same way as the presently hazardous solvents are used. We will substitute SAFE STRIP in the gun cleaning application first, as it will be the easiest to monitor. After using SAFE STRIP to clean the guns, the excess SAFE STRIP can either be wiped or rinsed off with water. Rinse water would be contained in a bucket, to insure that it did not enter the sewer prior to being tested. Similarly, paint lines can be purged with SAFE STRIP, then rinsed with water or simply used with paint. The first flush of paint will carry off any remaining SAFE STRIP, and painting can begin as normal. We have found that painters usually spray the first few moments of paint into a test sheet to insure that their lines are free of air and contaminants anyway, so this will not represent a new application procedure for them. Booth cleanup can easily be accomplished with SAFE STRIP, using it on a rag. SAFE STRIP used to clean guns and lines, as well as paint overspray, should be used as soon as possible after painting. SAFE STRIP is not as effective as methylene chloride or MEK on paint which has had a chance to cure. Economic Considerations We recognize that Georgia Shelf is not overly motivated to spend more money on material simply because it is environmentally preferred. SAFE STRIP will cost more money to purchase than either MEK or Meth. However, because SAFE STRIP is far less volatile than either of the other solvents presently used, it will last longer in use. Rough data indicates that SAFE STRIP lasts about six times as long as the equivalent amount of MEK or Meth when used in a bucket/tank cleaning application. Once the full environmental costs of the hazardous solvent are taken into account, (facility insurance, costs of mandatory OSHA and DOT training, manifests and RCRA reporting), the actual cost-in-use of SAFE STRIP will be roughly equivalent to that of MEK/METH. Further, the ISP RESPOND Environmental Management Service Program, detailed below, will reduce the cost of handling spent SAFE STRIP. This could even tip the economic scales in favor of SAFE STRIP over MEK/Meth. Environmental Considerations ISP offers a pick-up service for users of SAFE STRIP and related N-Methyl Pyrrolidone products manufactured by ISP. The basis of the program is simple. Once the customer has determined that his spent SAFE STRIP is not hazardous as defined by RCRA, an ISP distributor will either pick up the spent material or request that it be shipped to a central collection point. From that point ISP, working in support of the distributor, will take the material and have it distilled back into raw material used for reformulation. The TCLP test used to determine hazard characteristics is free to the customer, and there is no charge for the treatment of the spent material, once it is back in ISP s possession. The ISP RESPOND Program is an innovative approach to the management of spent solvents made with N-Methyl Pyrrolidone. - continued - 3

7 Ney Ultrasonics Case Study #3-Page 1 Case Study: Paint Gun Cleaning/Paint Clean-up By: Kerry Pfrimmer & Jim Schleckser, Ney Ultrasonics, Bloomfield, CT (800) Summary Georgia Shelf has a spot cleaning problem involving removal of paint and other coatings from spray guns, input lines and spray booths. They have historically used methylene chloride (METH) and methyl ethyl ketone (MEK). Management is not sensitive to the level of emissions or the legal factors involved in METH releases. Due to the wide range of materials to be removed and the partial cross linking of the coatings, an aggressive solvent is recommended to remove them. An engineered N-Methyl Pyrolidone (NMP) should be seriously evaluated for replacement of the chlorinated solvents currently in used. A second alternative would be a volatile terpene. An improvement in the gun cleaning could be obtained with a single ultrasonic process tank with the same chemistry. This would eliminate operator involvement and disassembly of the gun. Proposed Process Booth Clean-Up The booth clean-up would use the NMP on a rag. The booth would be wiped down while the exhaust is going to reduce the exposure and the NMP would be allowed to dry. The contaminated rags should be drummed and disposed in proper manner. Gun Clean-Up The manual method of cleaning the guns can be replaced with a NMP ultrasonic tank. The solvating effect of the chemistry plus the agitation of the ultrasonics combine to cleaning the internals of the gun without disassembly. After the solvent is contaminated, it should be disposed of properly. Input Line Cleaning The input lines should be cleaning in the same manner. The NMP would be pumped through the lines to remove any residual coating. Since the coatings are probably not crosslinked at all, the removal of the chemistry will be quite easy. This solution can be used multiple times before disposal.

8 OCS Systems Case Study #3 CASE STUDY #3 - Paint Gun Cleaning / Paint Cleanup - Solution! O.C.S. has found this to be one of the more difficult, but not impossible problems to solve, especially if the company management and painters are unwilling to change. Sometimes when those who are exposed to the methylene chloride and MEK are made more aware of the very real health risks, rather than air emissions, they will be more willing to change. The O.C.S. H2002U is an effective paint stripper on latex, enamels and lacquers. The two products work slower on urethane and will not touch hardened epoxys. The O.C.S. products will remove the paints from the guns by artificially enhancing the chemistry, such as heated ultrasonics. This would also eliminate the need for the use of a screwdriver and a rag for removal of paint patches. The O.C.S. H2002U in the ultrasonic heated to 150 F with a 5:l to 6: 1 dilution ratio would take 15 to 30 minutes to clean the gun, depending on the amount of time the paint has been in the gun. Paint lines could still be purged in the same manner as currently being done by using the O.C.S. H2002U at a 4: 1 dilution ratio, rinsing with clean water, but the line would have to have air blown through to dry it. This, unfortunately, would require more time in that process. The booth cleanup would be done by spraying affected areas with the 0. C.S. H2002U at a 4: 1 dilution ratio, let stand for 5 minutes, wet rag with the O.C.S. H2002U and wipe. The advantages of using the O.C.S. H2002U and ultrasonics are: biodegradability, non-toxic, non-flammable, non-combustible, and the ultrasonics being able to clean the equipment without the painter having to spend as much time to manually clean. Another advantage is that if the painter were to use the O.C.S. to prepare the part to be painted, the company may be able to use more water based paints because the O.C.S. makes up to a 15,000 pound better bond withthose materials, thus making their use more viable. The largest advantage is the health and safety of using the O.C.S. H2002U. The disadvantages of using O.C.S. H2002U are change, increased time for line purge, and paint booth cleanup. The O.C.S. H2002U would also evaporate, although much slower than the methylene chloride or MEK, leaving waste paint drums.

9 OxyChem Case Study #3: Paint Gun Cleaning/Paint Cleanup Problem MEC is not a VOC, and therefore, does not contribute to ozone production. If ozone containment is their largest concern, MEC is not a contributing factor. MEK is regulated as a VOC. If Georgia Shelf is concerned with total HAP emissions, emissions of both solvents must be reduced. The largest problem for Georgia Shelf is their management s inability to recognize the true problem. While their obvious solution to some is to replace MEC and MEK with non-regulated products that supposedly work as well, this solution is temporary at best. Proposed Cleaning Chemistry/Equipment The first solution Georgia Shelf should investigate is decreasing or controlling their evaporative losses of each solvent. They should investigate the use of vapor control technology such as the use of a cleaning both with exhaust fans connected to a carbon absorption recovery drum. Tighter in-plant controls of solvent usage, and the use of an explosion-proof distillation still to reclaim and reuse spent solvent are also advised. By controlling these fugitive emissions, they could go a long way in reducing their reportable emissions. If all efforts to change their solvent use pattern fail, Georgia Shelf should evaluate switching from MEK and, if necessary MEC, non-hap listed solvent with good properties. One such solvent is monochlorotoluene (MCT or Halso 99). Monochlorotoluene has a Kauri-Butanol Value of 110. In an adhesive solvency test, MCI was compared to 1,1,1 and showed a much greater aptitude for dissolving resinous products. MCT is used in combination with MEC in some paint removing products, and has been used as a rubber solvent. It has a slower evaporation rate than MEC or MEK, which can be both a benefit and a drawback. Parts may take longer to dry, but slower solvent evaporation could mean that less solvent is lost to the atmosphere. If immediate evaporation of the solvent is truly necessary, paint guns could be set in a ventilated paint booth after cleaning to help air dry the solvent Halso 99 is not listed as an Air Toxic nor as one of the Clean Air Act HAPS. Its emissions are not currently reported under SARA Title III, Section 313. Like the products mentioned earlier, Halso 99 is not an ozone depleting product. Its pricing is similar to MEC or 1,1,1 prior to the introduction of its excise tax, making it a very economical choice as well.

10 NON-PANELIST SUBMISSIONS

11 CRC Industries, Inc. Case Study #3 Case Study #3 - Paint Gun Cleaning/Paint Cleanup If company management does not perceive a problem it would be difficult to implement changes. Both methylene chloride and MEK are inexpensive; both are excellent cleaners and dry very quickly. The only reason to change are environmental and safety. Quick evaporating solvents are either VOCs or halogenated (with a couple of exceptions). Since methylene chloride is usually not considered a VOC, worker safety is the issue. If exposure is kept below the PEL and STEL, methylene chloride can be used safely. MEK is considered a VOC. If the company is interested in reducing VOC emissions, MEK use should be discontinued. N-methylpyrrolidone is a good paint remover substitute. It is more expensive than methylene chloride and takes longer to evaporate. The company does not have to deal with waste because their cleaners have been evaporating. Low vapor pressure cleaners (non-voc) will not disappear. Using low vapor pressure cleaners will force the company to deal with residue and waste. These may be issues that the company prefer to ignore until emissions become important. Case Study #4 - Solvent for Parts Washer CRC can offer several possible solutions Heavy Duty Degreaser II - a proprietary blend of chemicals that has flash point over 215" F. This is an excellent cleaner that evaporates completely. Since Heavy Duty Degreaser II is completely nonchlorinated, costs relating to disposal of waste are minimal. Available in aerosol cans, one and five gallon cans and 55 gallon drums. Natural Degreaser - loo% terpene - based cleaner. Excellent cleaner, moderate evaporation rate, low residue, good biodegradation characteristics. Available in aerosol cans, 5 gallon pails and 55 gallon drums. Complex Blue - industrial strength, water-based degreaser. Penetrates quickly to remove grease and oil. Contains no butyl, chlorinated or petroleum solvents, bleach, ammonia or abrasives. Available in pump bottle, one and five gallon cans and 55 gallon drums.

12 Case Study #3 Jet Edge is an innovative manufacturer of of ultra high water pressure jet cleaning equipment. Our environmentally safe and high performance equipment is employed throughout the world. Our equipment operates at 36,000 psi and can use up to 7 gpm of water. Water is the only medium we use to remove coatings and perform surface preparation. Water has the ability to remove tough coatings from substrates without changing the profile on the substrate material. Our equipment has been approved to strip the paint off of the aluminum shell of aircraft. This operation was previously performed with MEK (see enclosed article). In addition, our equipment is used in the automotive industry to remove paint buildup on paint carriers (see enclosed article). Our process also ensures superior adhesion because our equipment leaves the substrate contaminant free. The water used by our equipment is filtered down to.45 micron and capable of removing all contaminants on a surface. Currently, we have just started to work with companies in solving in plant problems similar to the question posed in Case Study #3. Instead of using a chemical bath an employee could use one of our wands to clean the booth and the paint gun, as long as the gun is not too delicate. The paint line could be cleaned as well if the material is durable enough to withstand the force generated by our water stream. The water that is used primarily evaporates into the air. All solid material falls to the floor and can be contained and treated, if necessary. Water treatment is necessary only when the material being removed is hazardous. Our equipment is being used to remove lead paint in a number of cities in the U.S. One of the reasons our equipment is preferred is the small amount of water that is used in the process and that needs to be treated. Another benefit of our equipment is the speed in which it cleans the surface. The increased speed would allow the paint line to operate longer. Our equipment capital cost for this type of operation would be approximately $65,000. The operating costs for the machine are approximately $5.00/hr. I have calculated that the Georgia Shelf Company spends approximately $22,000 a year in buying JMEK. The combination of the reduction in chemical and the increase operating time would allow our equipment to pay for itself in less than three years. Jet Edge, Inc. 825 Rhode Island Avenue South, Minneapolis, MN (612) (800) JET-Edge FAX (612)

13 Orange Sol, Inc. Case Study #3-Page 1 CASE STUDY #3 - Paint Gun Cleanup Summary Although there are alternative solvent products available to Georgia Shelf, they clearly lack any significant impetus to change from their current practices. Fundamental Issues The fundamental issues of this case are largely behavioral in nature: Workers find the MEK and methylene chloride easy to use, and they perform well. Workers don t appear to be very concerned regarding their own personal safety. Workers are not sensitive to environmental issues. Management is not aware of waste emissions at the plant. Management is not aware of Clean Air Act Amendments and how they relate to Georgia Shelf. The technical issues are really secondary to the case: The paints being cleaned are fresh urethane, latex, and enamel. Guns are cleaned by solvent purge, then immersion. Some hand wipe cleaning of the booth is done. Discussion At this point in time, Georgia Shelf has no incentive to change their solvent practices. There is little that alternative solvents can offer a company in this position. At some future time, events such as: Regulatory fines Worker lawsuit/worker s Comp. Insurance rate hike Pollution fines/fees Cleaning solvent surcharges will force Georgia Shelf to place a more direct economic value on their solvent activities, and lead to some positive changes.