brake cleaning with water-based cleaning systemsinfohouse.p2ric.org/ref/39/38526.pdf · water-based...

BRAKE CLEANING WITH

WATER-BASED CLEANING SYSTEMS

Perchloroethylene products, including (PERC), a chlorinat- brake cleaner. The ed solvent, is a Facilities eliminafe solvenfs ban will be effective major component

cleaners used by thousands of auto repair facilities in the country. The chemical poses several health and environmental problems.

First, PERC is a suspect carcinogen, and workers and community members living near auto repair shops are exposed to high concentrations of the chemical. Second, PERC can enter the sewer through improper handling and disposal of spent water-based parts cleaners that contain brake cleaner residues; this poses a problem for local wastewater discharge agencies. Third, PERC may end up in the soil and groundwater below the auto repair shops; this can lead to contamination of drinking water.

The California Air Resources Board (CARB) regulates consumer products in California. On April 27,2000, the CARB board banned PERC and other chlorinated solvents in automotive aerosol

of aerosol brake and cut cosfs

6 2000 John Wiley & Sons. Inc

at the point of use on December 31, 2002. Thousands of facilities in the state will have to adopt alternatives. Other

solvent-based aerosol brake cleaners are available, and some shops may convert to these cleaners. Water-based brake cleaners are also effective, and can be adopted by virtually all shops.

This article describes a project that was conducted to test and demonstrate water-based brake cleaners as alternatives to solvent aerosol products.

Background: Brake Cleaning Project The Institute for Research and Technical

Assistance (IRTA) is a nonprofit organization established in 1989 to assist firms in reducing or eliminating their use of solvents and ozone-

Kafy Wolf and Mike Morris

Pollution Prevention Review / Summer 2000 / 13

depleting substances. Operations targeted by [ R I A include general cleaning, precision cleaning, handwipe cleaning, electronics, paint strip- ping, coatings, and adhesives.

With funding from U.S. EPA's Environmental Justice Pollution Prevention (EJP2) Program, from 1997 through 1999, IRTA conducted a develop- mental study of water-based cleaners as alternatives to solvent aerosol cleaners for brake cleaning in auto repair facilities. Other partners in the

project included CallEPA's Department of Toxic The demonstration project involved

_. . . ..

Control (DTSC), the of Los Ang.eles

testing seven water-based brake cleaning formulations in five different types of equipment in 10 auto repair facilities to determine their feasibility and to optimize their

of Sanita;ion, the County Sanitation Districts of LOT

conditions of use. ~

Angeles, the South Coast Air Quality Management District

(SCAQMD), and the New Partnership Foundation (NPF), a community group. Although water- based cleaners have been used to some extent in brake cleaning, there has previously been no sys- tematic evaluation of their performance.

The demonstration project involved testing seven water-based brake cleaning formulations in five different types of equipment in 10 auto repair facilities to determine their feasibility and to optimize their conditions of use. Other project goals included testing the spent water-based cleaners to determine if they should be handled as hazardous waste or if they met wastewater discharge standards, and analyzing and comparing the cost of using the water-based and the aerosol cleaning systems.

In an earlier EPA EJP2 project, IRTA, DTSC, the City of Los Angeles Bureau of Sanitation, and SCAQMD tested, demonstrated, and optimized water-based cleaners for parts cleaning in auto repair facilities as alternatives to mineral spirits.

As a result of the project, SCc\QhID, one of the largest air regulatory agencies in the world, adopted a regulation requiring a conversion in repair and maintenance cleaning to cleaners with 50 grams per liter or less of volatile organic compounds (VOCs) by January 1, 1999. This regulation affected 40,000 parts cleaners in Southern California-25,000 in auto repair facilities and 15,000 in industrial facilities. The transition away from mineral spirits to water-based cleaners in repair and maintenance cleaning is now almost complete in the South Coast Basin.

During the earlier parts cleaning EJP2 project, the project team analyzed the spent water cleaning baths. Some of these spent baths contained PERC and other chemicals, such as toluene or xylene, that are used in aerosol brake cleaners. The wastewater discharge agencies participating in the project expressed concern about the possibility of brake cleaner compo- nents, particularly PERC, entering the sewer. Because the use of water-based cleaners i n parts cleaners opens a new pathway to the sewer, the project team wanted to minimize the environmental impact. This was the motivation for the project team to propose the second EJP2 project to see whether aerosol brake cleaners could be eliminated altogether.

In March 1996, EPA deemed PERC exempt from VOC regulations. In late 1996, CARB also deemed PERC exempt. The EJP2 project team was concerned that there would be an increase in PERC use in brake cleaner because of CARB's action. IRTA asked CARB to evaluate the risk posed to the surrounding community by PERC brake cleaner, and several wastewater discharge agencies asked CARB to monitor the use of PERC in aerosols. CARB agreed to collect data on the use of PERC in brake cleaner for several years to determine if there was an increase in its use after the exemption from VOC regulations. CARB also began evaluating the risk posed to the sur-

I 14 / Summer 2000 / Pollution Prevention Review Katy Wolf and Mike Morris

rounding community from PERC in aerosol brake cleaners.

In May 1998, CARB made a formal decision to develop a regulation on aerosol PERC brake cleaner. CARB has now adopted a ban on PERC aerosol brake cleaner and on PERC used in other automotive products. Anticipating the substitu- tion possibilities, CARB also adopted a ban on trichloroethylene and methylene chloride in automotive consumer products.

What This Article Covers Aerosol brake cleaners are used in most auto

repair shops in the country. This article begins by describing brake cleaning operations and how the aerosol cleaners are used. It then moves to a dis- cussion 6f water-based cleaning formulations and brake cleaning equipment that can be used in place of the solvent aerosol brake cleaners. The article then focuses on the 10 facilities where water-based cleaning systems were tested and provides the analysis results of the spent water- based brake cleaning baths. Finally, information is presented on case studies for seven facilities that converted to water-based cleaners at the conclusion of the project.

Brake Cleaning Operations There are 329,000 auto repair facilities in the

country. A survey by Brake & Front End Magazine indicates that, in 1996, facilities in the United States performed an average of 15.6 brake jobs each week. During brake jobs, it is conventional for technicians to clean with aerosol brake cleaners. These aerosol brake cleaners contain chemicals that are suspect carcinogens, pose other toxicity problems, or are VOCs which contribute to photochemical smog.

Brake repair operations begin when the vehi- cle is driven into a repair stall or bay for a brake system examination. Brake service operations can include inspections, adjustments, brake pad

replacements, and rotor resurfacing. The wheels are elevated and removed, and the brake assem- bly is inspected. There may be loose dust on the drums and brake assemblies; this is commonly removed and cleaned by vacuuming, wet or dry wiping or brushing, blowing with compressed air, or a combination of these methods. Then the necessary repairs are made and the brake system is reassembled and readjusted. Some technicians clean the brakes again to remove fingerprints and oil once the system is assembled. Vehicles are often test driven to verify that the repairs have been effective.

Brake cleaners are commonly used during brake servicing. These products, which can be either aerosol or liquid, are designed to remove a variety of contami- nants, including oil, grease, brake fluid, dust, and dirt. Some

Brake cleaners are commonly used during brake servicing.

aerosol brake cleaners are based on PERC; other non-chlorinated brake cleaners are based on solvents such as toluene, xylene, mineral spirits, and acetone. Some of the liquid brake cleaning systems rely on mineral spirits or terpenes. Others rely on the use of water-based cleaners which may or may not contain solvent additives. Solvents that may be used in water-based cleaners include terpenes, glycol ethers, and alcohols. Some technicians use no brake cleaners, some use them once during a brake service job, and some use them several times during a job.

As part of its work to determine if a toxics reg ulation on PERC brake cleaners was required, CARB conducted a survey of auto repair facilities in California. CARB also visited several facilities that perform brake jobs and estimated the emis- sions and risk to the surrounding community from exposure to PERC in brake cleaners.

CARB surveyed the manufacturers of PERC aerosol brake cleaning products in 1997. Twenty-

Brake Cleaning with Water-Based Cleaning Systems Pollution Prevention Review I Summer 2000 / 15

two of 37 surveys were returned. CARB received information on 89 different brake cleaning products, 33 of which contained PERC. The manufacturers reported selling more than two million units ranging in size from 10 ounces to 55 gallons. The PERC content in these products was between 22 and 98 percent. PERC usage was cal- culated from the survey information. CARB estimates PERC use of about three million pounds in brake cleaner annually in California.

CARB estimates that there are about 21,000 facilities that perform brake service in California.

They include service stations, car dealer-

CARB estimates that there are ships, fleets, brake

about 21,000 facilities that perform shops, and general automotive repair brake service in California. shops. CARB staff visited 137 facilities to col-

lect data on brake cleaning. The staff performed cancer risk assessments for 55 of the facilities. The cancer risk posed to the surrounding community ranged from 0.3 to 60 in a million. In some cases, the risk posed by the use of PERC brake cleaner was much higher than the ambient PERC risk in California, which is placed at five in a million.

CARB has adopted a ban on PERC in aerosol brake cleaner and other automotive consumer products. CARB has also adopted a ban on two other chlorinated solvents-trichloroethylene and methylene chloride-in automotive consumer products so vendors will not substitute the two chemicals for PERC.

The ban on PERC automotive consumer products will likely spur a conversion to VOC solvent aerosol products. Most of these products contain solvents that pose toxicity problems. In some cases, although they have different toxicity end points, they may present as serious a threat as PERC. The water-based cleaners tested in this project are suitable substitutes for both PERC aerosols and non-PERC aerosols.

Demonstration Testing At the beginning of the project in 1997, IRTA

selected ten auto repair facilities that were willing to participate in the study to evaluate water-based brake cleaners. The ten facilities were located in Southern California and they included a service station, a brake shop that is part of a large chain, an auto dealership, a diesel repair facility, a facility that maintains city vehicles, and five small auto repair facilities. One of these facilities was already using a water-based brake cleaning system routinely.

The ten shops that were selected for participa- tion in the project included:

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Los Angeles Department of Water and Power, a city yard responsible for maintenance of city vehicles Diesel/Fuel Injection Specialties, a shop that maintains diesel vehicles Santa Monica Nissan, a dealership Midas, a member of a chain that specializes in mufflers and brakes Sunset Park Chevron, a service station UR#1, a small auto repair shop that specializes in Honda repairs Tomvo's, a small auto repair shop Carriage House, a small auto repair shop Prestige Auto Service, a small auto repair shop Santa Monica Auto Center, a general automotive repair shop

IRTA tested a variety of water-based cleaners and delivery systems during the two-year project, including performing a set of screening tests at Santa Monica Nissan. Several different water- based cleaners were tested for effectiveness. Spray bottle and equipment delivery systems were also tested. Over the next several months, the ten participating facilities were provided with different types of equipment and different water-based cleaners for testing.

r i i c

After the first set of tests, six of the spent water- based cleaning baths were analyzed. After the second set of tests, when the units had been rotated to different facilities, six of the spent water-based cleaning baths were again analyzed. The purpose of this analysis was to determine whether the spent baths were hazardous waste and whether they met wastewater discharge standards.

Water-Based Formulations for Brake Cleaning There are thousands of water-based cleaning

formulations that are offered by hundreds of vendors across the country for numerous applications. These cleaners are often sold as liquid con- centrates. Depending on the application, between 3 and 50 percent of the cleaner is required. TQe concentrate is diluted with tap or deionized water, again depending on the application. Some of these cleaning formulations have solvent additives; the most common solvents added to water-based cleaners are terpenes and glycol ethers.

As part of the project protocol, IRTA decided not to test cleaners that have solvent additives. IRTA inadvertently did test one water-based cleaner with solvent additives because the vendor did not disclose that information until the testing was almost completed. Despite the presence of solvents, this cleaner did not perform as well as the other cleaners tested.

Several different water-based cleaners were tested during the project. Although a few of the facilities tested water-based cleaners in spray bottles, there was general agreement that the water- based cleaners worked more effectively in brake cleaning equipment.

Seven water-based cleaners were tested at the facilities in brake cleaning equipment. The cleaners were of the following types:

Two were enzyme cleaners-one offered by Orange Line/Gray Mills, and one by

EvergreedForBest. These cleaning systems consist of a neutral surfactant-based enzyme cleaner. Microbes that are added to the cleaning solution biodegrade oil. Three were neutral cleaners--one offered by Mirachem, one by W.R. Grace (called Daraclean 236), and one called Green Unikleen. Two were alkaline cleaners-one offered by W.R. Grace (Daraclean 257), the other by Safety Kleen.

Testing indicated that the concentration of cleaner in brake cleaning formulations is less important than it is in parts cleaning formulations. Brake cleaning is, in effect, an easier task; any liquid, even one with a relatively low active ingredient concentration, is likely to be suitable for brake cleaning. The concentration used during the study was 25 percent* In Some cases, however, after the water-based ‘lean- ers had been used for several months, the concentration was probably much lower, perhaps as low as 5 percent. The cleaners still performed adequately.

In the earlier project on parts cleaning, it was determined that water-based cleaners needed to be heated to be effective. Brake cleaning is a less demanding task, however, and the water-based cleaners were very effective during this project even when they were unheated.

Neutral water-based cleaners are the most suitable cleaners for this sector. When technicians use the brake cleaning equipment that was tested during this project, they have hand contact with the cleaning formulations. Because highly alkaline formulations would damage the skin, formulations that have a more neutral pH are preferred.

Testing indicated that the concentration of cleaner in brake cleaning formulations is less important than it is in parts cleaning formulations.

Brake Cleaning with Water-Based Cleaning Systems Pollution Prevention Review I Summer 2000 / 17

Brake Cleaning Equipment As mentioned above, IRTA tested a few of the

cleaners in spray bottles and the technicians in some of the facilities judged the cleaning to be adequate. There was agreement, however, that spray bottle cleaning was not as effective as equipment cleaning. Five different types of equipment were tested in the course of the project. These equipment types are described in more detail below.

t _ _ - ~

Sink-on-a-Drum Parts Cleaner In January 1999, the SCAQMD began requir-

ing repair and maintenance cleaning to be performed with cleaners that contained no more than 50 grams per liter VOCs. In response to this requirement, most auto repair shops converted to water-based sink-on-a-drum parts cleaners. IRTA wanted to investigate whether these parts cleaners could also be used for brake cleaning. I f so, companies would be able to use the same equipment for both parts cleaning and brake cleaning.

The sink-on-a-drum unit consists of a sink work area resting on a drum which contains the liquid cleaner. Both the sink and the drum can be manufactured out of plastic or metal; the units tested for brake cleaning were made of plastic. The sink contains a drain which provides the only interface between the user and the reservoir. The drums in typical units hold 15 to 40 gallons of liquid. Sink-on-a-drum units have a recirculat- ing pump, and they allow cleaning liquids to be heated, generally to 105 or 110 degrees F. In many applications (parts cleaning, for instance), water-based cleaners are more effective when they are heated.

' Virtually all sink-on-a-drum units have a faucet, and most units also include a flow brush; the brush is effective for cleaning parts and brakes. Some units include a filter for removing oil and particulate material. The units generally

require a 110 volt electrical outlet, which is common in auto repair facilities.

Two different sink-on-a-drum units were tested during the brake cleaning project. One of these, a typical small parts cleaner, is shown in Exhibit 1. Note that the cleaning system has a faucet and a flow brush. The system is mounted on wheels, which is convenient for moving the parts cleaner to the proper position for servicing brakes.

Heated Brake Cleaning Unit As part of the project, KleenTec, a company

that manufactures parts cleaners and brake cleaning equipment, agreed to design a special brake cleaning unit with a heater; there were no such units on the market at the time. IRTA wanted to test such a unit to investigate whether the cleaning effectiveness was improved if the water-based cleaner was heated. KleenTec provided IRTA with two heated units for testing during the project.

Exhibit 1. Small Parts Cleaner

Katy Wolf and Mike Morris

J

Exhibit 2. Heated Brake Cleaning Unit Exhibit 3. Unheated Brake Cleaning Unit

A picture of one of these units is shown in Exhibit 2. It is very similar to a small parts cleaner. The reservoir holds about 15 gallons of liquid; generally, the unit is filled with 10 gallons of liquid for brake cleaning. The unit sits on wheels, making it convenient to move under cars requiring brake servicing. The sink area of the cleaning unit contains a brush, a faucet, and a drain.

Unheated Brake Cleaning Unit Clayton is one of the leading suppliers of

brake cleaning equipment in the country. The company provided one of their units for testing

during the project. This unit is shown in Exhibit 3. It is very similar to the brake cleaning unit shown in Exhibit 2, but it has no heater. It has a liquid capacity of about 15 gallons and is mounted on wheels. Again, the unit is generally filled with 10 gallons of liquid for brake cleaning. The sink includes a brush, a faucet, and a drain.

Birdbath Brake Cleaning Unit Four birdbath brake cleaning units were pro-

vided for project testing by Applied Cleaning Technologies and Unikleen. The example birdbath unit shown in Exhibit 4 is made by R&D. It contains a reservoir on the bottom that holds

Pollution Prevention Review / Summer 2000 I19

. ~ _ ~ _ _

Brake Cleaning with Water-Based Cleaning Systems

Exhibit 4. Birdbath Brake Cleaning Unit Exhibit 5. Stand Mounted Brake Cleaning Unit

about eight gallons of liquid. The reservoir is commonly filled with five gallons of liquid for brake cleaning. A metal sink, which contains a brush and a drain, is mounted on a thin tube which can be adjusted in height. The metal sink can be raised several feet to lie directly under a car which has been elevated for brake service.

i

Stand Muunfed Brake Cleaning Unit Three different stand mounted brake clean-

ing units were tested during the project; a picture of one of these is shown in Exhibit 5 . These units are very simple batch loaded cleaners which contain a brush and have a liquid capacity of about five gallons. The reservoir is commonly filled with two gallons of liquid for brake cleaning. They are generally placed on a wheeled stand that can be moved around the shop as required.

Facility Testing Program During the field testing, seven different clean-

ing formulations and five generic types of equip-

20 / Summer 2000 / Pollution Prevention Review

ment were tested. All of the facilities except one routinely purchased solvent aerosol cleaners. Midas has a policy that does not allow any aerosol products in their facilities; they had already been using a water-based brake cleaner exclusively for several years. The Midas shop was included in the study project because of this policy and because IRTA wanted to compare their cleaner with others.

Two of the other facilities that participated in the project, UR#1 and DieseliFuel Injection Specialties, indicated that they rarely used a cleaner for brake cleaning. These two facilities purchased solvent aerosol cleaners routinely, however, for other purposes. These two facilities did some testing of the water-based cleaners during the project.

IRTA had most of the facilities test one or two different types of water-based brake cleaning methods in the course of the project. In a few cases, IRTA asked the facilities to test PERC aerosol brake cleaners supplied by IRTA so that they would have a comparison for the water-

Katy Wolf and blike Morris

F

based cleaners. Exhibit 6 summarizes the different systems tested by the participating facilities.

At the end of the project, 7 of the 10 facilities converted to a water-based cleaning system. Midas kept their original water-based system, and UR#1 and Diesel/Fuel Injection Specialties did not clean their brakes at all.

Analysis of Spent Baths One of IRTA's project partners, the City of Los

Angeles Bureau of Sanitation, analyzed the spent cleaning baths after they had been used for several months by the participating facilities. The purpose of this analysis was to determine whether the spent water-based brake cleaning formulations were hazardous waste, or if they met wastewater discharge standards. This was an important piece of the proj-

Exhibit 6. Project System Testing

ect because the results of the analysis dictate how the spent water-based cleaners should be handled.

The spent baths from six of the facilities were analyzed after the first round of testing and several months of use. Spent baths from six facilities were also analyzed after the second round of testing. All 12 baths were analyzed for heavy metals. For cadmium, chromium, copper, nickel, lead, and zinc, the analysis was conducted for total metals and dissolved metals on all but two of the spent baths. In addition, all of the spent baths were analyzed for oil and grease. All of the baths in the first round of testing, and one of the baths in the second round, were analyzed for volatile organic compounds. Four of the baths that were analyzed in the second round of testing were also tested for asbestos.

Facility First Round Testing Second Round Testing Permanent System

UR#1

Tomvo's

DieseVFuel Injection Specialties

Carriage House

L.A. City Department of Water and Power

Prestige Auto Service

Santa Monica Nissan

Midas

Santa Monica Auto Center

Sunset Park

Spray bottles/ Daraclean 236 Daraclean 257

Aerosol

Spray bottles/ Daraclean 257

Parts cleaner/ Orange Line enzyme

Birdbath/ Unikleen

Clayton/ Mirachem

KleenTec/ Daraclean 236

KleenTec/ Unikleen

Birdbath/ Daraclean 236

Parts washer/ Mirachem


Evergreen/ ForBest enzyme



Spray bottles/ Unikleen


Birdbath/ Unikleen


Clayton/ Mirachem


None


None


Birdbath/ Unikleen



Safety-Kleen

Clayton/ Daraclean 236 and Birdbath/ Daraclean 236


Brake Cleaning with Water-Based Cleaning Systems Pollution Prevention Review Summer 2000 I21

None of the spent baths met City of Los Angeles discharge standards for oil and grease. Although other discharge agencies have different standards, they are generally lower than the 600 mg/l level established by Los Angeles. For example, the oil and grease limit in the Orange County Sanitation District is 100 mg/l. It is therefore likely that virtually all spent brake cleaning baths would exceed the oil and grease limits in all locations.

This finding indicates that spent brake cleaning baths cannot be discharged unless they are treated to remove oil and grease. Clarifiers are

generally effective at this task. Some auto repair facilities have

This finding indicates that spent brake cleanina baths cannot be dis-

1 clarifiers, but most do not. The clarifiers at

charged unless they are treated to remove oil and grease. - auto repair facilities

are commonly three- stage clarifiers, where the first stage removes the oil and the second stage removes solids. These clarifiers should be effective in reducing the oil and grease levels.

Some of the spent baths also contained metals at levels that exceed discharge standards in the City of Los Angeles. Other discharge agencies could have even lower limits. Clarifiers are not effective for treating metals; the spent baths containing high levels of metals would have to be shipped off-site as hazardous or non-hazardous waste.

Four of the spent baths contained copper at levels that esceeded the Soluble Threshold Limit Concentration (STLC), the level set by DTSC in California. None of the baths contained compo- nents that exceeded the federal RCRA hazardous waste levels, however. Thus, the spent baths that contained copper esceeding the STLC level could be handled as non-RCRX California-Only hazardous waste. Eight of the spent baths did not contain metals that exceeded the STLC. These

baths could be handled as non-hazardous waste in California and in other parts of the country.

One proviso on the classification of the baths concerns fish toxicity. In California, a waste is classified as hazardous if the acute aquatic 96- hour LC-50 is less than 500 mg/l. LC-50 is defined as the lethal concentration at which 50 percent of the fish die. None of the spent baths vas analyzed for fish toxicity in this project. A few of the baths might exhibit fish toxicity, and this wou!d also make them California-Only hazardous waste.

Facilities in California that have clarifiers and decide to treat their spent baths would have to obtain a tiered permit from the local Certified Unified Program Agency (CUPA) if the spent bath was classified as California-Only hazardous waste. If it was not classified as California-Only hazardous waste, a tiered permit would not be necessary. Four of the 12 spent baths tested were classified as California-Only hazardous waste and a tiered permit would be required if these baths were treated in a clarifier.

The same holds true if a facility decides to treat the spent bath in an evaporator. I f the bath is California-Only hazardous waste, a tiered permit from the CUPA would be required. In addition, in this case, an air district permit tor the evaporator could be required as well.

Facilities outside California would not have to obtain a hazardous waste treatment permit for using a clarifier or an evaporator, but they could be required to obtain an air permit for treatment in an evaporator.

Cost Issues During the study project, seven of the partici-

pants decided to convert to water-based brake cleaning. One of the participant shops, \Lidas, did not have to convert because it was already using a water-based cleaning system. Two of the other shops, UR#1 and DieseliFuel Injection

22 / Summer 2000 / Pollution Prevention Review Katy Wolf and Mike Morris

Specialties, do very little, if any, cleaning during brake servicing. IRTA analyzed the costs for the seven facilities that converted.

Two of the vendors that supplied cleaning systems for the project, Applied Cleaning Tech- nologies (ACT) and Unikleen, gave four of the participating shops the cleaning units free of charge. Three other vendors, EvergreedForBest, Clayton, and KleenTec, agreed to give three of the participating shops a brake cleaning unit at a reduced price.

Although the seven facilities received their water-based cleaning equipment at no cost or at a reduced price, the cost analysis assumed that each facility paid the retail equipment price. This approach was used so that the cost analysis would reflect the true cost to a facility for the conversion to water-based cleaning.

The retail price of the heated KleenTec water-based brake cleaner is $1,022. The price of the birdbath brake cleaner is $697. The price of the unheated Clayton unit is $550. The price of the tabletop mounted ForBest batch brake cleaner is $350. It was assumed that all shops would pay cash for the equipment. It was also assumed that the cleaning equipment would have a five-year useful life; this is a conservative assumption, and it is likely that the units would actually last longer.

Most of the facilities indicated that use of solvent aerosol cans and water-based brake cleaning equipment requires the same amount of labor. This assumption was made for all of the facilities.

The heated and unheated brake cleaning units were assumed to hold 10 gallons of liquid. The birdbath brake cleaning units were assumed to hold five gallons. The stand mounted units were assumed to hold two gallons of liquid.

The heated brake cleaning equipment requires electricity for heating the water and running the pump. In IRTA's earlier work on parts cleaning in auto repair facilities, it was assumed that a small


water-based parts cleaner would have an electricity cost of about $10 per month, or $120 per year; here, the same assumption was made for the heated KleenTec unit. The unheated Clayton unit electrical cost was assumed to be half that of the heated KleenTec unit, or $60 per year. The small table top mounted brake cleaning units and the birdbath units have negligible electricity cost.

The analysis above indicates that most of the spent baths are non-RCRA hazardous waste. Three options were examined for disposal of the spent cleaner: clarifier disposal, shipment off-site as RCRA hazardous waste, and shipment off-site as non-RCRA California-Only hazardous waste.

In two cases, the facilities have clarifiers. It was assumed that the spent bath would be discharged at no cost for one of these facilities. For the Other

ity, three scenarios were considered: one where the spent baths are discharged, one where the bath is RCRA hazardous waste, and one where the waste is California-Only waste.

In one instance where the facility uses a parts cleaner as a brake cleaner, the spent bath is serviced by the manufacturer. In another instance, the facility has both a brake cleaner and a parts cleaner; the contents of the brake cleaning unit are frequently poured into the parts cleaner so that the filter can clean up the solution. The parts cleaner is serviced periodically by the manufacturer. In the three other instances, two scenarios were considered: one where the spent bath is RCRA hazardous waste, and one where the spent bath is non-RCRA hazardous waste.

A generator of less than 1,000 kilograms of hazardous waste in any calendar month may accumu- late waste for 180 days under certain conditions.

Most of the facilities indicated that use of solvent aerosol cans and water-based brake cleaning

equipment requires the same amount of labor.

Pollution Prevention Review I Summer 2000 / 23

Most auto repair facilities fall into this category. For all cases analyzed, an accumulation time of 180 days was assumed for the hazardous waste.

In Southern California, where a regulation requiring water-based parts cleaning is in effect, most facilities would dispose. of their spent brake cleaning formulation in their parts cleaners. The brake cleaning units use small amounts of liquid. After several months of use, much of the liquid will evaporate and disposal with the spent water cleaner in the parts cleaner would not exceed the liquid capacity of the units. In these cases, there is no incremental cost for disposal of the spent brake cleaning fluid. In other parts of the country, where mineral spirits are still used for parts cleaning, the brake cleaning formulation would probably be disposed of separately at a higher cost. In this analysis, to be conservative, it is assumed that the spent brake cleaning formulation will be disposed of separately.

Total Cost

Case Studies The case studies presented below include infor-

mation about each facility, describe the cleaning units that each facility tested and ultimately selected, and compare the facility’s cost of using water- based cleaning instead of solvent aerosol cleaners.

$1,625 $337 $270 Tomvo’s Tom Vo is the owner of Tomvo’s, a full service

auto repair shop in Garden Grove, California. The shop has three full-time employees, and the workers at the shop repair between five and eight cars each day.

IRTA began working with Tomvo’s in 1995 as part of a project designed to assist facilities in converting to water-based parts cleaning. The shop converted from a mineral spirits to a water- based parts cleaner. In 1997, IRTA asked Tomvo’s to participate in the brake cleaning project.

Tomvo’s had been using PERC aerosol brake cleaners for many years. The shop performs about

25 brake jobs each week. Tom Vo estimates that about one can of PERC brake cleaner was used for each brake job. At a cost of $1.25 for each aerosol can, the total yearly cost to the facility for using the PERC brake cleaner was $1,625.

During the project, Tomvo’s tested an enzyme water-based brake cleaner and found it to be suitable. At the conclusion of the project, Applied Cleaning Technologies (ACT) provided a birdbath brake cleaning unit to Tomvo’s at no cost. The shop has been using the new brake cleaning system for about two months. “The water brake cleaning system performs well. It’s just as good as the aerosols,” says Tom Vo.

Says Mike Halbert of ACT, “The cost of the birdbath brake cleaning unit is $697 and the unit should last at least five years.” Even if Tomvo’s had purchased the water-based brake cleaning unit, the cost for brake cleaning to the facility would be lower. “The aerosols are high cost. I’m saving money and I’m using a product that’s better for the environment and the workers,” says Tom Vo.

Tomvo’s Annual Cost Comparison: Aerosol Brake

Cleaning California

Equipment Cost Cleaner Cost $1,625 Disposal Cost $1 50

Carriage House Carriage House is a general automotive repair

shop located in Harbor City, California. The shop has two employees and repairs all kinds of automotive systems.

IRTA began work with Carriage House in 1995. The facility tested several water-based parts cleaners for IRTA during an EPA project. Carriage House converted to an enzyme parts cleaner in 1998. The shop also agreed to test and evaluate brake cleaning systems for IRTA.

24 / Summer 2000 / Pollution Prevention Review Katy Wolf and Mike Morris

Mike Walsh, owner of Carriage House, estimates that the shop performs three brake jobs each week. About one-fourth of a can of aerosol brake cleaner was used for each brake job. On this basis, at a cost of $3 per can, the annual cost to the shop for using aerosol brake cleaners was $117.

Carriage House tested two different enzyme systems for brake cleaning. The system the shop liked the best is made by ForBest and provided by Evergreen. The equipment is a small batch cleaning system mounted on a wheeled stand. The enzyme

cleaners a few years ago. The facility agreed to test water-based brake cleaning systems during the project sponsored by EPA.

At the beginning of the brake cleaning project, DWP was still using aerosol brake cleaners. The shop performed about three brake jobs each week and used about one and a half aerosol cans for each service. At a cost of $3 per can for the aerosols, the total annual cost of using the brake cleaner amounted to about $700. Shortly after the brake cleaning project began, DWP converted

cleaning formulation contains microbes that biodegrade the oil. Carriage House uses the same system for parts cleaning. Periodically, the cleaning formulation in the brake cleaning unit is poured into the parts cleaner, where it is filtered and cleaned up. New formulation from the parts cleaner is used to replenish the brake cleaning unit.

“Both the parts cleaner and the brake cleaner are very effective. The advantage of the enzyme system is that it cleans itself. It does not require disposal, and that reduces costs,” says Mike Walsh. “I got the brake cleaner at a lower cost, but I’d be saving money even if I paid full price,” he says. “The aerosol cans are expensive and bad for the environment.”

to a water-based brake cleaner. The Safety-Kleen system utilizes a batch clean-

ing unit that holds about five gallons of cleaner and is mounted on a wheeled stand for conven- ience. The annual service cost for using this system was lower than the aerosols, at $563.

DWP tested spray bottles with various different water-based cleaners during IRTA’s brake cleaning project. The facility especially liked one of the cleaning formulations, Green Unikleen. This cleaner is neutral, has no solvent additives, and was already being used by the shop in their parts cleaners. At the end of the project, Unikleen gave DWP a birdbath brake cleaning unit at no charge. The shop converted to the Unikleen cleaner at a cost of less than $200 annually.

Carriage House Annual Cost Comparison: Says Ernie Peltz, an equipment mechanic who

for parts cleaning and it also does really well for Equipment Cost Cleaner Cost $117 brake cleaning. The aerosols are bad for the envi- Total Cost $117 $70 ronment and the workers. We saved money by

using the water-based brake cleaner.”

uses all the systems at DWP, “I like the Unikleen Cleaning Cleaning

Los Angeles Department of Water and Power The Los Angeles Department of Water and

Power (DWP) has replaced its solvent aerosol brake cleaners with a water-based cleaning system

10s An eles Department of Water and Power Annua !Cost Comparison:

Aerosol Brake Safety-Kleen Unikleen Cleaning Water Cleaning Water Cleaning

at its Palmetto facility in downtown Los Angeles. The DWP facility participated in IRTA’s test

and demonstration program for water-based parts cleaners. DWP converted to water-based parts $702 $563 $177


P

Prestige Auto Service Prestige Auto Service, owned by Ken Nellish,

is a small full service auto repair facility located in Santa Monica, California.

Ken Nellish agreed to participate in IRTA’s water-based brake cleaning project. Mr. Nellish prides himself on being progressive. The shop performs about 20 brake jobs a month and used an estimated four cans of aerosol brake cleaner for each brake job. At a cost of about $1 per can, the shop spent $960 on aerosol brake cleaners each year.

Prestige tested a variety of cleaners in spray bottles at the beginning of the project. The two cleaners that performed the best, Daraclean 236 and Daraclean 257, are made by W.R. Grace and provided by Applied Cleaning Technologies (.4CT).

Prestige also tested two types of brake cleaning systems. The first was an unheated wheeled plastic brake cleaning unit made by Clayton. The cleaning unit is similar to a small parts cleaner with a sink and a reservoir for the water-based cleaning fluid. The second system tested by Prestige was a heated cleaning unit, similar to the Clayton unit, and made by KleenTec. KleenTec had designed the unit specifically for the IRTA project to evaluate whether heating the formulation increased the performance.

Ken Nellish liked both the systems he tested. “The water-based cleaning systems are good alternatives to the aerosols for brake cleaning. At first I didn’t think they’d be effective, but they were.”

ACT provided Prestige with a birdbath brake cleaning system at the end of the project at no cost. “The birdbath unit works very well,” says Nellish. “Even if I paid full price for the system, I still would be saving money. I’m not exposing myself or my neighbors to the chemicals in the aerosol any longer.”

I Aerosol Brake Cleanina

Prestige Auto Service Annual Cost Comparison: Water-Based Brake Cleaninp

RCRA I California

Equipment Cost Cleaner Cost Disposal Cost

Total Cost

$1 50

$337 $270

Santa Monica Nissan Santa Monica hissan is part ot the Miller

Automotive Group, which has eight service facilities in the Southern California area. The dealership employs 35 service people and operates 18 service bays. Twenty technicians provide servicing for about 100 cars each day.

In 1997, IRTA approached Santa Xionica Nissan about participating in an EPA-sponsored brake cleaning project to test and demonstrate water-based brake cleaners. The Santa Monica Nissan technicians assisted IRT.4 in performing screening testing for different brake cleaning formulations. Over the next 18 months, Santa Monica Nissan helped IRTA to test a specially designed heated brake cleaning unit and an unheated birdbath design brake cleaner with two different water-based cleaning formulations.

Santa Monica Nissan historically used solvent aerosol brake cleaner. The company purchased about 600 aerosol cans each year at a cost of $2 per can. The total cost for brake cleaning amounted to $1,200 annually.

Atter several months of testing the different water-based brake cleaning systems, Santa Monica Nissan decided to convert to the units the technicians liked the best. “We made the conversion from mineral spirits to water-based parts cleaners and the workers liked it better,” says Jack Miller, Service Manager at Santa Monica Nissan. “My people also liked the water-based brake cleaners and we decided to convert away from the aerosol cans.”

26 I Summer 2000 / Pollution Prevention Review Katy Wolf and Mike Morris

The technicians liked the heated brake cleaner the best of those they tested. KleenTec provided one unit at a reduced cost to the facility and Santa Monica Nissan plans to purchase one additional unit over the next few months. Says Chuck Kennedy, the KleenTec representative, “Our heated unit is new to the market and we have had good feedback on its performance from mechanics.” The cleaning system uses a W.R. Grace cleaner called Daraclean 236, which is supplied by Applied Cleaning Technologies (ACT). “The cleaner is neutral, which will protect the mechanics’ hands, and it cleans well in the automotive sector,” says Mike Halbert of ACT.

Although they were not required by regulation to use water-based cleaners, Santa Monica Nissan prides itself on being progressive. “We want to be out in front on environmental issues. We’re saving money on the water-based brake cleaner, we’re reducing our workers’ exposure, and we’re a good neighbor to the community.”

Santa Monica Nissan Annual Cost Comparison:

I Aerosol Brake Water-Based Brake Cleaning Cleaning I Clarifier 1 California I RCRA

Equipment Cost Cleaner Cost Electrical Cost Disposal Cost $200

Total Cost

Santa Monica Auto Center Dane Brown is the manager of Santa Monica

Auto Center, a busy full-service auto repair facility in Santa Monica, California. The facility has 10 employees, five of them technicians.

Santa Monica Auto Center performs an average of 10 brake jobs each week. The shop had used PERC aerosol brake cleaner for the last few years. Two cans of brake cleaner were used for each brake service. At a cost of $1.40 per can, the total annual cost to the facility for brake cleaning was $1,456.

IRTA asked Santa Monica Auto Center to participate in an EPA project designed to test water- based brake cleaners in 1997. During the first set of tests, the shop tested a birdbath style brake cleaning unit provided by Applied Cleaning Technologies (ACT). The cleaning agent was a neutral cleaner, Daraclean 236, which is made by W.R. Grace. During the second set of tests, the technicians tested a plastic brake cleaning unit made by Clayton that used a cleaner made by Mirachem. This unit is a mobile, sink-on-a-drum configura- tion with a brush for the cleaning solution.

The mechanics liked both the cleaning systems better than the aerosol cans for brake cleaning. ACT provided the birdbath system to Santa Monica Auto Center at no cost and Clayton offered the plastic unit at a reduced cost. The mechanics liked the Daraclean 236, and ACT is supplying the cleaner for both units. “The cleaner is neutral so it doesn’t hurt the mechanics’ hands,” says Mike Halbert of ACT.

Clayton has been supplying water-based cleaning equipment to the industry for years. “Technicians often like this system better than aerosol cans for brake cleaning,” says Jim Clayton. “The water systems are better for the worker.”

Even though Santa Monica Auto Center is using two brake cleaning units, their costs have been reduced dramatically. If the shop had paid full retail price for the two units, their costs would still be much lower. “We reduced our costs and we’re using cleaners that are better for the worker and the environment,” says Dane Brown. “What could be better?’’

Santa Monica Auto Center Annual Cost Comparison:

Aerosol Brake Cleaning

Equipment Cost Cleaner Cost $1,456 Electrical Cost Disposal Cost

Water-Based Brake Cleaning California

$400 $110

Total Cost $1,456 $854 $564

Brake Cleaning with Wafer-Based Cleaning Systems

Sunset Park Chevron Sunset Park Chevron is a service station locat-

ed at a busy intersection near the freeway in Santa Monica, California. The station does a large volume of business. In the past, in addition to the traditional services of a gas station, the facility did repair and servicing. Recently, the station has decided to become a Smog Check Only station.

IRTA worked with Sunset Park Chevron in an earlier project designed to assist facilities in converting from mineral spirits parts cleaners to water-based cleaners. The shop tested a few systems and converted to a small plastic sink-on-a- drum parts cleaner that used a water-based cleaning formulation made by Mirachem. In the brake cleaning project, IRTA asked Sunset Park Chevron to test the Mirachem parts cleaner for brake cleaning. Since the parts cleaner had wheels, it could be moved throughout the service station as required for brake jobs.

Sunset Park Chevron had traditionally used solvent aerosol cans for brake cleaning. The shop performed an average of eight brake jobs each week and typically used one spray can for each brake servicing. At a cost of $3 per can, the total cost of the brake cleaner was $1,248 annually.

Sunset Park Chevron began testing the Mirachem parts washer as an alternative cleaning system during brake jobs. The technician liked this cleaning method much better than the aerosol cans. “We did not see a need to continue using the aerosol cans,” says Karim Rawji, manager of the service station. “We were already using the water-based cleaner for parts cleaning. Since it performed well on brakes, we decided to use it there too.”

The service station replaced a mineral spirits parts cleaner and aerosol cans of brake cleaner with one water-based parts cleaning unit. The total annual cost of using the water-based system is about half that of the solvent cleaning methods. Says Karim Rawji, “The water cleaner is bet-

$1,248 $468 $181 $60

$1,957

ter for the environment and the workers, and it also reduced our costs.”

$100

$440 $1 99 $1 20

$859

Sunset Park Chevron Annual Cost Comparison:

Water-Based Cleanina

Aerosol Brake Cleaner/ Mineral Spirits Parts Cleanina

Equipment Cost Chemical Cost Service Cost Labor Cost Electrical Cost

Total Cost

Summary and Conclusions The PERC aerosol brake cleaner used today

by thousands of auto repair facilities poses a threat to the workers in these facilities and to the surrounding communities. PERC is a suspect carcinogen, and it has caused soil and groundwater contamination at many facilities where it has been used. Other solvents used in aerosol brake cleaning formulations also include several that are classified as toxics; they, too, pose a threat to people who come in contact with them.

The project discussed in this article involved testing water-based cleaners as alternatives to solvent aerosol products for brake cleaning. Seven water-based cleaning formulations and five different types of cleaning equipment were tested in 10 auto repair facilities. The spent baths were analyzed for oil and grease, heavy metals, and asbestos.

The most important of the project findings is that water-based brake cleaners are as effective as solvent-based aerosol brake cleaners for cleaning during brake jobs. IRTA investigated hand pump spray bottle delivery systems, but these were not as effective as the water-based cleaning equipment that most of the facilities adopted. Five types of equipment are available

28 / Summer 2000 / Pollution Prevention Review

P

Katy Wolf and Mike Morris

for use with water-based cleaners in brake cleaning, and they are all effective. Technicians liked all the systems, but had personal prefer- ences. Neutral water-based cleaners are the most suitable for this sector because technicians have hand contact with the formulations when they use the equipment.

A second finding is that much of the solvent- based aerosol is used for purposes other than brake cleaning. The companies that sell aerosol solvent cleaners may label them as brake cleaners, engine degreasers, carburetor cleaners, or parts cleaners. In addition to brake cleaning, the facilities that participated in the project used the aerosol solvent cleaners for all kinds of tasks, including cleaning oil pans during an oil job or cleaning surfaces. Water-based cleaners would be. suitable for these activities.

A third finding is that, in many cases, no cleaning during brake jobs is necessary. The brakes can be disassembled, repaired, and reassembled without a cleaning step. Two of the facilities that participated in this project indicate that they do little if any cleaning during brake jobs.

The fourth finding is that the spent water- based cleaning baths did not meet wastewater discharge standards because they contained high levels of oil and grease. None of the spent baths was classified as RCRA hazardous waste, but one- third of the spent baths were classified as California-Only hazardous waste. The baths that were hazardous waste in California had concentrations of copper that exceeded the threshold level. Many brake pads contain copper, and this could be the source of the metal. Of the four spent baths that were analyzed for asbestos, two were found to contain the substance. The levels of asbestos, however, were below the California state level for hazardous waste.

The fifth finding is that virtually all shops could convert to water-based brake cleaners, and

that the water-based systems are lower in cost than the solvent-based aerosols. One of the shops that participated in the study was already using a water-based The seven shops that converted cleaning system. Seven from solvent aerosol to water- of the other partici- based brake cleaners reduced pants converted to their brake cleaning costs by 25 water-based systems at to 93 pecent. the end of the project. The two remaining facilities indicate that they do not use cleaners when they perform brake jobs.

The seven shops that converted from solvent aerosol to water-based brake cleaners reduced their brake cleaning costs by 25 to 93 percent. One of the facilities that participated in the testing is part of a chain that does not allow the shops to use aerosol products of any kind. This suggests that not only are aerosols unnecessary for brake cleaning, they are unnecessary for any cleaning tasks in auto repair shops.

Acknowledgment

cle was provided by EPA Region IX. Funding for the project discussed in this arti-

For Further Information For additional information on topics covered

in this article, see: Morris, M. & Wolf, K. (1999, September).

Institute for Research and Technical Assistance, in partnership with Cal/EPA's Department of Toxic Substances Control, City of Los Angeles Bureau of Sanitation, Los Angeles County Sanitation Districts, and South Coast Air Quality Management District. Brake cleaning in auto repair facilities: The conversion to water (prepared for U.S. EPA).

Booklet prepared by the Institute for Research and Technical Assistance, translated by the New

Brake Cleaning with Water-Based Cleaning Systems Pollution Prevention Review I Summer ' 2000

Partnership Foundation in conjunction with Foundation in conjunction with CallEPA's CallEPA's Department of Toxic Substances Department of Toxic Substances Control. Control. Switching to water-based cleaners for

Individual case study conversions, prepared by the Institute for Research and Technical Assistance and translated by the New Partnership

automotive brake cleaning. Disclaimer Mention of any specific product in this arti-

cle does not constitute an endorsement of that product.

Or. Katy Wolf is executive director of the Institute for Research and Technical Assistance (IRTA). Mike Morris is a scien- tist and project manager at IRTA.

30 / S w v " 2000 / Pollution Prevention Review Katy Wolf and Mike Morris

brake cleaning with water-based cleaning systemsinfohouse.p2ric.org/ref/39/38526.pdf · water-based...

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