Back

PROPOSAL:

Status Report on Efficiency of Aqueous Solvents on Hard to Clean Heavy-Duty Truck Parts Subject to Rule 1171

SYNOPSIS:

On February 13, 1998, the Board authorized the Chairman to execute a contract with CE-CERT to conduct a study to identify and evaluate the cleaning efficiency of water-based cleaning systems on "hard to clean" parts with "extra heavy-duty" grease and grime for repair and maintenance operation of heavy-duty trucks subject to Rule 1171, and to report the results to the Board.

COMMITTEE:

Technology, January 15, 1999, Reviewed

RECOMMENDED ACTION:

Receive and file.

Barry R. Wallerstein, D.Env.
Executive Officer

Background

VOC emissions generated from solvent cleaning and degreasing operations contribute significantly to the South Coast Air Basin’s emissions inventory. The 1997 AQMP calls for significant reduction in VOC emissions from these operations by year 2010. Starting January 1999, AQMD’s Rule 1171 requires cleaning materials used in repair and maintenance operations to contain no more than 50 grams of VOC per liter of cleaning solvent. A large number of zero- or low-VOC aqueous solvents are already commercially available and comply with the limits of Rule 1171. However, these available aqueous solvents have specific applicability and can only be efficient if used correctly in proper applications and concentrations.

On February 13, 1998, on recommendation of the AQMD staff and the California Trucking Association (CTA), the Governing Board approved the award of a $50,000 contract to CE-CERT to conduct a study to identify and evaluate the cleaning efficiencies of specific aqueous solvents on cleaning baked, carbonized, or chemically combined grease and grime in repair and maintenance operation of heavy-duty trucks.

Study Update

Staff from the AQMD and the CTA selected five suitable facilities in the South Coast Air Basin to participate in this study. The participating facilities were Shepherd Machinery Company, Power Systems Associates, Phibro-Tech Inc., DSL Transportation Company, and Nationsway Transport Service Company. The operation at these facilities included cleaning "hard to clean" parts with "extra heavy-duty" grease and grime, in the application areas of service, rebuild and overhaul of engines and transmissions for heavy-duty trucks and off-road equipment.

For this study, the AQMD and the CTA staff selected Mirachem and Intech (W.R. Grace) to supply aqueous solvents and equipment for the cleaning operations of the above facilities. The aqueous solvents were used by the participants in their normal daily cleaning operations for six weeks. The study was monitored and coordinated with the vendors and the participating facilities by CE-CERT.

After the conclusion of the study CE-CERT issued a draft final report on September 21, 1998. Upon receiving comments from AQMD and CTA staff, and the participating facilities, the final report was issued in January, 1999.

Study Conclusions

The study was conducted by recording performance data by mechanics during actual parts cleaning, and on-site interviews of mechanics and shop managers by CE-CERT staff.

It was determined that the vast majority of difficult to clean truck parts were satisfactorily cleaned with aqueous solvents. Only transmission friction plates containing adhesives between laminated materials could not be cleaned; in that instance the water reacts chemically with the paper and adhesive.

The aqueous solvents worked better than petroleum based solvents on plastic parts. In addition, the use of an ultrasonic unit at Shepherd Machinery, installed by the company’s own initiative, enabled the mechanics to clean the dirtiest parts in a shorter period of time than with petroleum based solvents. The unit can replace up to four sink-on-drum stations. The cost of this type of unit is $5,000 to $7,000. Smaller units are available costing around $1,500.

Most mechanics interviewed preferred aqueous solvents due to more acceptable odor and less skin irritation.

It was therefore concluded that aqueous solvents evaluated in this study were effective in cleaning "hard to clean" parts for heavy-duty truck repair and maintenance operations.

Status

There are approximately 17,000 facilities with a total of 40,000 cleaning units in the South Coast Air Basin subject to the requirements of Rule 1171 for repair and maintenance cleaning operations. According to the information submitted by the suppliers to the AQMD, thirty-five to forty percent of the cleaning units have already been converted and are in compliance with the requirements of Rule 1171. It is the AQMD’s goal to bring the remaining facilities in compliance within the next six months by conducting workshops, outreach efforts, and issuing Notices to Comply.

Implementation

Staff will implement Rule 1171 with the following considerations:

1. In cooperation with the CTA and the Department of Toxic Substance Control, conduct workshops to inform shop owners of proper use of aqueous cleaners, including drying methods and waste handling options.
2. Provide assistance in the determination of solvent cleaning systems for operations that are not presently conducted with aqueous solvents.
3. Build on the current outreach foundation by sending a Compliance Advisory to all facilities subject to the rule and initially, in most cases, issue Notices to Comply requiring a compliance affidavit certifying conversion has been completed. Notices of Violation will be issued for non-compliance with Notices to Comply, when violations are observed in conjunction with certain other compliance problems and after the interim implementation period has passed.
4. Support a group variance for transmission parts with laminated materials since they cannot be cleaned with the available aqueous products at this time.
5. Evaluate "in-frame" engine cleaning operations and wipe cleaning methods (to consider safety and hazards where flame are present) for additional rule category considerations in the future.

Summary

The project was concluded successfully. Staff wishes to thank CTA and participating companies for their assistance in this matter. A copy of the final report of this study released in January, 1999 is available at the AQMD’s library.

/ / /