SEPA
        United States
        Environmental Protection
        Agency
             Office of Research and
             Development
             Washington, DC 20460
EPA/600/R-99/004
February 1999
Environmental Technology
Verification
        Ultrasonic Aqueous
        Cleaning Systems
        Smart Sonic Corporation
        SMART SONIC®

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                                          EPA/600/R-99/004
                                            February 1999
     Environmental Technology
           Verification Report

    Ultrasonic Aqueous Cleaning Systems
   Smart Sonic Corporation, SMART SONIC®
                       By
              Pat Bennett, Project Manager
         California Environmental Protection Agency
          Department of Toxic Substances Control
   Office of Pollution Prevention and Technology Development
            Sacramento, California 85814-0806

            Norma M. Lewis, Project Manager
             Sustainable Technology Division
       National Risk Management Research Laboratory
                Cincinnati, Ohio 45268
        Cooperative Agreement No. CR 824433-01-0
     U.S. ENVIRONMENTAL PROTECTION AGENCY
      OFFICE OF RESEARCH AND DEVELOPMENT
NATIONAL RISK MANAGEMENT RESEARCH LABORATORY
              CINCINNATI, OHIO 45268
                                       Printed on Recycled Paper

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                                        Notice

The information in this document has been funded in part by the U.S. Environmental Protection
Agency (EPA) under a Cooperative Agreement number CR 824433-01-0 with the California Envi-
ronmental Protection Agency (Cal/EPA), Department of Toxic Substances Control (DTSC).  This
verification effort was supported by the Hazardous Waste Treatment and Pollution Prevention Pilot
Project under the US EPA Environmental Technology Verification (ETV) Program. This verifica-
tion effort has been subjected to EPA's and Cal/EPA's peer and administrative review, and has been
approved for publication as an EPA document.

This verification is limited to the use of the Smart Sonic aqueous cleaning systems for cleaning
RMA (rosin mildly activated), no-clean, and water washable solder pastes from printed circuit board
stencils. US EPA and DTSC makes no express or implied warranties as to the performance of the
Smart Sonic aqueous cleaning systems. Nor does US EPA and DTSC warrant that the  Smart Sonic
aqueous cleaning systems are free from any defects in workmanship or materials caused by negli-
gence, misuse, accident or other causes.  Mention of corporation names, trade names, or commercial
products does not constitute endorsement or recommendation for use of specific products.

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                                           Foreword

The Environmental Technology Verification (ETV) Program has been established by the U.S.
Environmental Protection Agency (EPA) to evaluate the performance characteristics of innovative
environmental technologies across all media and to report this objective information to the permit-
ters, buyers, and users of environmental technology. EPA's Office of Research and Development
(ORD) has established a five year pilot program to evaluate alternative operating parameters and
determine the overall feasibility of a technology verification program. ETV began in October 1995
and will be evaluated through October 2000, at which time EPA will prepare a report to Congress -
containing the results of the pilot program and recommendations for its future operation.

EPA's ETV Program, through the National Risk Management Research Laboratory (NRMRL), has
partnered with the California Department of Toxic Substances Control (DTSC) under an ETV Pilot
Project to verify pollution prevention, recycling, and waste treatment technologies.  This Pilot
Project focuses  on, but is not limited to, hazardous waste management technologies used in several
EPA "Common Sense Initiative" industry sectors: printing; electronics; petroleum refining; metal
finishing; auto manufacturing; and iron and steel manufacturing.

The following report reviews the performance of the Smart Sonic Aqueous Cleaning Systems.
These cleaning  systems are used in the electronics  industry to clean various types of solder pastes
from printed circuit board stencils.

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                                  Acknowledgment

Pat Bennett, DTSC's Project Manager, wishes to acknowledge the support of all those who helped
plan, implement the verification activities, and prepare this report. In particular, a special thanks to
Ms. Norma Lewis, Project Manager, and Mr. Sam Hayes, Quality Assurance Manager, of EPA's
National Risk Management Research Laboratory in Cincinnati, Ohio.

DTSC's Project Manager acknowledges the efforts by DTSC's Project Team members and by
DTSC's Technical Review Panel. DTSC's Project Team members included Mr. Bruce LaBelle, Mr.
Dick Jones, and Mr. Phil Loder.  DTSC's Technical Review Panel included Mr. John Wesnousky,
Mr. Wolfgang Fuhs, and Mr. Tony Luan.

DTSC's Project Manager would also like to thank the printed circuit board manufacturers for partici-
pating in the verification activities. A special thanks to the printed circuit board facilities that al-
lowed DTSC's Project Team to conduct on-site observations and inspections. These facilities and
contacts included:
      Mr. Thanh Vo
      PNY Electronics
      Santa Clara, CA

      Mr. Mike Moynihan
      Technetics
      El Cajon, CA

      Mr. Roger Lara
      Wiltron
      Morgan Hill, CA
Mr. Tom Lord
Kaiser Electronics
San Jose, CA

Mr. Bob Dudley
Altron
Fremont, CA
                                          IV

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                                                                         EPA/600/R-99/004VS
     x>EPA
                 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                             Office of Research and Development
                                  Washington D.C. 20460
    ENVIRONMENTAL TECHNOLOGY VERIFICATION STATEMENT
    TECHNOLOGY TYPE:

    APPLICATION:

    TECHNOLOGY NAME:

    COMPANY:
    ADDRESS:


    PHONE:
    FAX:
ULTRASONIC AQUEOUS CLEANING SYSTEMS

CLEANING PRINTED CIRCUIT BOARD STENCILS

SMART SONIC®

SMART SONIC CORPORATION
2373 TELLER ROAD, #107
NEWBURY PARK, CALIFORNIA 91320

(805) 499-7440
(805) 375-5781
The U.S. Environmental Protection Agency has created a program to facilitate the deployment of
innovative environmental technologies through performance verification and information dissemina-
tion. The goal of the Environmental Technology Verification (ETV) Program is to enhance environ-
mental protection by substantially accelerating the acceptance and use of innovative, improved, and
more cost-effective technologies. The ETV Program is intended to assist and inform those individu-
als in need of credible data for the design, distribution, permitting, and purchase of environmental
technologies. This verification statement provides a summary of performance results for the Smart
Sonic Aqueous Cleaning Systems, registered trademark SMART SONIC®.

PROGRAM OPERATION

The EPA's ETV Program, in partnership with recognized testing organizations, objectively and
systematically documents the performance of commercial ready environmental technologies.  To-
gether, with the full participation of the technology developer, they develop plans, conduct tests,
collect and analyze data, and report findings. Verifications are conducted according to a rigorous
workplan and established protocols for quality assurance. Where existing data are used, the data
must have been collected by independent sources using similar quality assurance protocols. EPA's
ETV Program, through the National Risk Management Research Laboratory (NRMRL), has
partnered with the California Department of Toxic Substances Control (DTSC) under an ETV Pilot
Project to verify pollution prevention, recycling, and waste treatment technologies.
                                                                            FEBRUARY 1999

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TECHNOLOGY DESCRIPTION

Smart Sonic Corporation developed the Model 2000 and Model 4200 ultrasonic aqueous cleaning
systems to replace l,l,2-trichloro-l,2,2-trifluoroethane (CFC-113), 1,1,1-trichloroethane (1,1,1-
TCA) and isopropyl alcohol (IPA) based systems used in the electronics industry to clean various
types of solder pastes from printed circuit board stencils.

Smart Sonic's stencil cleaning technology consists of Smart Sonic's proprietary 440-R SMT Deter-
gent*, ultrasonic generator and 40 kHz piezoelectric transducers, stainless steel wash tank, rinse tank
(included in semi-automated system), and control devices.

The semi-automated Model 2000 system is approximately 3 feet high with a 40 x 44  inch base . This
unit has a separate wash tank and a manual rinse station. The automated Model 4200 system is
approximately 50 inches high with a 36 x 62 inch base.  The pneumatic lift used on this model
extends 36 inches for a total system height of 86 inches. This system has one tank for washing with
an automated rinse over the wash tank.
                   Model 2000
Model 4200

440-R SMT Detergent
The combination of Smart Sonic's 440-R SMT Detergent and ultrasonics enables the removal of
solder pastes from printed circuit board stencils. Detergent surfactants act as wetting agents to
saturate the solder paste layer that is left on the stencil surface (from solder paste printing operation).
The ultrasonics then produce an intense scrubbing action, through cavitation and implosion of
microscopic bubbles that enhances removal of the saturated solder paste layer. Ultrasonics are often
more effective in cleaning hard-to-reach surfaces (i.e., small stencil apertures) than brushes and hand
wipes. The cleaning bath is operated at room temperature, eliminating any potential effects to
stencil from cleaning solutions requiring higher temperatures.
                                             VI
                                                                                 FEBRUARY 1999

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EVALUATION DESCRIPTION

Between May and September 1998, an evaluation of two ultrasonic aqueous cleaning systems,
developed by the Smart Sonic Corporation, was conducted using field and laboratory qualitative and
quantitative data. The aqueous cleaning systems include Smart Sonic's Model 2000 and Model 4200
systems. The objectives of this evaluation were to verify, through independent sources, the
following performance parameters:

   • the ability to remove RMA (rosin mildly activated), no-clean, and water washable solder pastes
     from printed circuit board stencils;

   • the content of volatile organic compounds (VOC) and halogenated compounds in the cleaning
     systems; and

   • characteristics or conditions from use of this technology which may pose a significant hazard to
     public health and the environment.

The evaluation consisted of:

  - cleaning performance validation through on-site visits of end-users and further validation through
   additional end-user phone contacts;
  - laboratory testing for select VOCs and halogenated compounds by California's SCAQMD using
   SCAQMD's Clean Air Solvent (CAS) Certification Protocol (CAS Protocol uses SCAQMD Test
   Method 313 - gas chromatograph/mass spectrometer);
  - laboratory testing for metals and pH by DTSC's Hazardous Materials Laboratory using EPA Test
   Method 6010/7470 and EPA Test Method 9040 respectively;
  - toxicological review of laboratory results and aqueous cleaner ingredients to determine if
   potential hazards to human health or the environment exist; and
  - industrial hygiene review of cleaning systems information manual and on-site safety
   observations.

Details of the evaluation, including data summaries and discussion of results may be found in the
report entitled " US EPA Environmental Technology Verification Report, Smart Sonic Aqueous
Cleaning Systems, SMART SONIC® (EPA/600/R-99/004)."
                                            Vll
                                                                                FEBRUARY 1999

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VERIFICATION OF PERFORMANCE

Performance results of Smart Sonic Corporation's aqueous cleaning systems, Model 2000 and
Model 4200, are as follows:

  • Cleaning Efficiency: In five facilities visited, DTSC's Project Team found no solder paste in
   stencil apertures when observed at 10X magnification. The size of stencil apertures ranged from
   12-50 mil (1 mil=.001 inch). All end-users removed excess solder paste from stencil prior to
   cleaning in the Smart Sonic aqueous cleaning systems. Cleaning times ranged from 60-90
   seconds. Four of the five end-users visited were using a 10% concentration of Smart Sonic's
   440-R SMT Detergent (10% concentration recommended by Smart Sonic).  The fifth end-user
   was using a 5% detergent concentration for removing water washable solder paste.

   [Additional Information: Eight additional end-users contacted via phone were satisfied with the
   Smart Sonic stencil cleaning systems and stated that the systems clean consistently and as good,
   if not better, than the previously used cleaning systems.  Previously used systems included CFC-
   113, 1,1,1-TCA and IP A. Alcohol and wipes were the most commonly used cleaning method.]

  • VOC Content: The 440-R SMT Detergent does not contain VOCs or halogenated compounds at a
   detection limit of 0.01% (v/v) using the SCAQMD's CAS Certification Protocol.

  • Metals Content: Metals analyses conducted by DTSC's Hazardous Materials Laboratory indicate
   that samples of Smart Sonic's 440-R SMT Detergent concentrate showed no hazardous metals
   above method detection limits.

  * pH Measurement: pH measurements conducted by DTSC's Hazardous Materials Laboratory
   indicates a 440-R SMT Detergent concentrate pH of 13. pH measurements conducted by
   DTSC's Project Team during on-site visits (using pH indicator paper with pH range 0-14)
   showed cleaning bath pH of 11 when using 10% 440-R SMT Detergent concentration.

  • Worker Health and Safety: While using Smart Sonic Aqueous Cleaning Systems, Model 2000
   and 4200, end-users should follow Smart Sonic's recommended safety practices as outlined in
   the User's Manual and 440-R SMT Detergent Material Safety Data Sheet (MSDS).  The only
   significant toxicity associated with the 440-R SMT Detergent concentrate is acute toxicity due to
   its highly alkaline nature. DTSC's Industrial Hygienist recommends end-users have an eye wash
   station and an MSDS available within close proximity to the cleaning systems.
                                           Vlll
                                                                               FEBRUARY 1999

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Results of the verification show that the Smart Sonic ultrasonic aqueous cleaning systems, Model
2000 and 4200, are capable of removing RMA (rosin mildly activated), no-clean, and water
washable solder pastes from printed circuit board stencils such that no solder paste remains in stencil
apertures at 10X magnification, provided that end-users follow Smart Sonic's cleaning guidelines.
The Model 2000 and 4200 cleaning systems do not contain select volatile organic compounds and
halogenated compounds above detection limit of 0.01% (v/v) using SCAQMD's CAS Certification
Protocol (April 1997). End-users should follow  Smart Sonic's operational and safety guidelines.

End-users should contact their stencil manufacturer prior to changing their cleaning process.
Changing from solvents to aqueous cleaning systems may require stencil modifications to make the
cleaning system and stencil compatible. In addition, the end-user should contact his/her local, state,
or federal regulatory authority regarding management of spent hazardous wastes generated from use
of the Smart Sonic aqueous cleaning systems (i.e., spent cleaning baths, rinse baths, and solids
containing  lead).
 U. W****-*-,
 E. Timothy Oppeit*           Date
 Director
 National Risk Management Laboratory
 Office of Research and Development
 United States Environmental
  Protection Agency
     fes T. Allen, Ph.D., Chief        Date
     ce of Pollution Prevention
I/and Technology Development
' Department of Toxic Substances Control
 California Environmental Protection Agency
    NOTICE: Verifications are based on an evaluation of technology performance under specific,
    predetermined criteria and the appropriate quality assurance procedures. EPA and Cal/EPA make no
    expressed or implied warranties as to the performance of the technology. The end-user is solely
    responsible for complying with any and all applicable federal, state, and local requirements.	
                                                                                  FEBRUARY 1999

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     Availability of Verification Statement and Report
 Copies of the public Verification Statement (EPA/600/R-99/004VS) and
Verification Report (EPA/600/R-99/004) are available from the following:

     (Note: Appendices are not included in the Verification Report.
         Appendices are available from DTSC upon request.)
    1. USEPA/NSCEP
      P.O. Box 42419
      Cincinnati, Ohio 45242-2419

      Web site: http://www.epa.gov/etv/library.htm (electronic copy)
               http://www.epa.gov/ncepihom/ (order hard copy)
   2. Department of Toxic Substances Control
      Office of Pollution Prevention and
           Technology Development
      P.O. Box 806
      Sacramento, California 95812-0806

      Web site: http://www.dtsc.ca.gov/sppt/opptd/etv/txppetvp.htm
           or   http://www.epa.gov/etv (click on partners)
                                                                  FEBRUARY 1999

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                                TABLE OF CONTENTS

Notice	„	ii
Foreword	iii
Acknowledgment	iv

ENVIRONMENTAL TECHNOLOGY VERIFICATION STATEMENT	 v

Executive Summary	 1

Section 1. Introduction	 5

Section 2. Description of Technology	 7

Section 3. Verification Activities and Results	 9

   3.1    Laboratory Testing Conducted by DTSC Project Team	 9
          3.1.1 Sampling of Smart Sonic 440-R SMT Detergent (Concentrate)	 9
          3.1.2 Results of VOC Analyses	 9
          3.1.3 Results of Metals Analyses	16
          3.1.4 Results of pH Measurement	17

   3.2    End-User Data Collection	17
          3.2.1  Summary of End-User Data	19

   3.3    On-Site Performance Validation	21
          3.3.1  Results of On-Site Performance Observations	 22

   3.4    IH / Toxicologist Review	24
          3.4.1  Results of DTSC's IH and Toxicologist Review	24

   Section 4. Review Existing Analytical Data Provided by SCAQMD	25

   Section 5. Hazardous Waste Management / Hazardous Waste Regulations	26

   Section 6. Vendor's Comments	26

   Availability of Verification Statement and Report	29
                                          XI

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                               LIST OF TABLES

Table 3-1.     Results of SCAQMD'sVOC Analyses	10
Table 3-2.     Results of SCAQMD's Spiked Sample Recovery Analyses	10
Table 3-3.     SCAQMD Targeted Hazardous Air Pollutants	11
Table 3-4.     SCAQMD Targeted Ozone Depleting Compounds	14
Table 3-5.     SCAQMD Targeted Compounds With Global Warming Potential	15
Table 3-6.     Results of DTSC's HML Metals Analyses	16
Table 3-7.     Results of DTSC's HML pH Measurements	17
Table 3-8.     Number and Type of End-User Questionnaire Responses	18
Table 3-9.     Number and Type of End-Users Visited by DTSC's Project Team	22
                              LIST OF FIGURES

Figure ES-1.  Smart Sonic cleaning systems	 2
Figure 1-1.    Description of PCB stencil and solder paste types	 6
Figure 2-1.    Smart Sonic cleaning system operating parameters	8
               APPENDICES (Available from DTSC Upon Request

 Appendix A: Brochure on Smart Sonic's Stencil Cleaning Systems
 Appendix B: Smart Sonic Sampling Trip Report, May 29, 1998
 Appendix C: VOC Analyses of End-Users 440-R SMT Detergent Samples, July 9, 1998
 Appendix D: Metals and pH analyses of End-Users 440-R SMT Detergent Samples,
      June 17,1998
 Appendix E: Original Questionnaire Responses
 Appendix F: Questionnaire Summary
 Appendix G: On-Site Observation and Inspection Results
 Appendix H: DTSC Industrial Hygienist Review: Memo
 Appendix I: DTSC Toxicologist Review: Memo
 Appendix J: VOC Analyses of Smart Sonic's 440-R SMT Detergent, October 14, 1997
 Appendix K: VOC Analyses Results of Smart Sonic's 440-R SMT Detergent,
      March 26, 1998
                                      Xll

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                             LIST OF ACRONYMS
1,1,1-TCA      1,1,1-trichloroethane
CAS           Clean Air Solvent
CCR           California Code of Regulations
CFC-113       1,1,2-trichloro-1,2,2-trifiuoroethane
CFR           Code of Federal Regulations
DI             De-Ionized (Water)
DTSC          Department of Toxic Substances Control
ETV           Environmental Technology Verification
GC/MS        Gas Chromatography/Mass Spectrometry
g/L            grams/Liter
GWC          Global Warming Compound
HML           Hazardous Materials Laboratory
IH             Industrial Hygienist
IPA            Isopropyl Alcohol
kHz            frequency (one thousand cycles per second)
mcg/gm        microgram/gram
mg/kg          milligrams/kilograms
mil            one thousandths inch (.001")
MSDS         Material Safety Data Sheet
NRMRL       National Risk Management Research Laboratory
ODC           Ozone Depleting Compound
PCB           Printed Circuit Board
RMA          Rosin Mildly Activated
SCAQMD      South Coast Air Quality Management District
US EPA       United States Environmental Protection Agency
VOC           Volatile Organic Compound
VOHAP       Volatile Organic Hazardous Air Pollutant
v/v            volume/volume
                                       Xlll

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                                 Executive Summary

The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the
nation's natural resources. EPA created the Environmental Technology Verification (ETV)
Program to facilitate the deployment of innovative technologies through performance verification
and information dissemination. The goal of the ETV Program is to enhance environmental
protection by substantially accelerating the acceptance and use of innovative, improved, and cost-
effective technologies.  The ETV Program is intended to assist and inform those individuals in
need of credible data for the design, distribution, permitting, and purchase of commercially-ready
environmental technologies.

EPA's ETV Program, through the National Risk Management Research Laboratory (NRMRL),
has partnered with the California Department of Toxic Substances Control (DTSC) under an ETV
Pilot Project to verify pollution prevention, recycling, and waste treatment technologies. The Pilot
Project focuses on, but is not limited to, several EPA "Common Sense Initiative" industry sectors:
printing; electronics; petroleum refining; metal finishing; auto manufacturing; and iron and steel
manufacturing.

Candidate technologies for these programs originate from both the private and public sectors and
must be market-ready.  Through the ETV Pollution Prevention, Recycling, and Waste Treatment
Pilot Project, developers are given the opportunity to have the performance of their technology or
product tested and evaluated under realistic laboratory or field conditions. By completing the
verification and distributing the results, EPA establishes a baseline for acceptance and use of these
technologies.

This pilot project evaluates the performance of two ultrasonic aqueous cleaning systems
developed by the Smart Sonic Corporation located in Newbury Park, California. Smart Sonic
Corporation developed these two ultrasonic aqueous cleaning systems to replace 1,1,2-trichloro-
1,2,2-trifluoroethane (CFC-113), 1,1,1-trichloroethane (1,1,1-TCA) and isopropyl alcohol (IPA)
based systems that are used in the electronics industry to clean various types of solder pastes from
printed circuit board stencils. The objectives of this evaluation is to verify, through independent
sources, the following performance parameters:

  •  the ability to remove RMA (rosin mildly activated), no-clean, and water washable solder
    pastes from printed circuit board stencils;

  •  the content of volatile organic compounds (VOC) and halogenated compounds in the
    cleaning systems; and

  •  characteristics or conditions from use of this technology which may pose a significant hazard
    to public health and the environment.

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Technology Description

Smart Sonic stencil cleaning technology consists of Smart Sonic's proprietary 440-R SMT
Detergent*, ultrasonic generator with 40 kHz piezoelectric transducers, stainless steel wash tank,
rinse tank (included in semi-automated system), and control devices.

The Smart Sonic stencil cleaning systems evaluated in this project include the semi-automated
Model 2000 and automated Model 4200 shown in Figure ES-1. The semi-automated Model 2000
system is approximately 3 feet high with a 40 x 44 inch base. This unit has a separate wash tank and
a manual rinse station. The automated Model 4200 system is approximately 50 inches high with a
36 x 62 inch base. The pneumatic lift used on this model extends 36 inches for a total system height
of 86 inches. This system has one tank for washing with an automated rinse over the wash tank.
                    Model 2000
  Model 4200
440-R SMT Detergent
                       Figure ES-1. Smart Sonic cleaning systems.

Evaluation Approach

The evaluation consisted of:

  - cleaning performance validation through on-site visits of end-users and further validation through
   additional end-user phone contacts;
  - laboratory testing for select VOCs and halogenated compounds by California's SCAQMD using
   SCAQMD's Clean Air Solvent (CAS) Certification Protocol (CAS Protocol uses SCAQMD Test
   Method 313 - gas chromatograph/mass spectrometer);

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  -   laboratory testing for metals and pH by DTSC's Hazardous Materials Laboratory (HML)
     using EPA Test Method 6010/7470 and EPA Test Method 9040 respectively;
  -   toxicological review of laboratory results and aqueous cleaner ingredients to determine if
     potential hazards to human health or the environment exist; and
  -   industrial hygiene review of cleaning systems information manual and on-site safety
     observations.

Verification of Performance

Performance results of Smart Sonic Corporation's aqueous cleaning systems, Model 2000 and
Model 4200, are as follows:

  •   Cleaning Efficiency: In five facilities visited, DTSC's Project Team found no solder paste in
     stencil apertures when observed at 10X magnification. The size of stencil apertures ranged
     from 12-50 mil (1 mil=.001 inch). All end-users removed excess solder paste from stencil
     prior to cleaning in the Smart Sonic aqueous cleaning systems. Cleaning times ranged from
     60-90 seconds.  Four of the five end-users visited were using a 10% concentration of Smart
     Sonic's 440-R SMT Detergent (10% concentration recommended by Smart Sonic). The
     fifth end-user was using a 5% detergent concentration for removing water washable solder
     paste.

     [Additional Information: Eight additional end-users contacted via phone were satisfied with
     the Smart Sonic stencil cleaning systems and stated that the systems clean consistently and as
     good, if not better, than the previously used cleaning  systems. Previously used systems
     included CFC-113,1,1,1-TCA and IP A. Alcohol and wipes were the most commonly used
     cleaning method.]

  •   VOC Content: The 440-R SMT Detergent does not contain VOCs or halogenated
     compounds at a detection limit of 0.01% (v/v) using the SCAQMD's CAS Certification
     Protocol.

  •   Metals Content: Metals analyses conducted by DTSC's Hazardous Materials Laboratory
     indicate that samples of Smart Sonic's 440-R SMT Detergent concentrate showed no
     hazardous metals above method detection limits.

  •   pH Measurement: pH measurements conducted by DTSC's Hazardous Materials Laboratory
     indicates a 440-R SMT Detergent concentrate pH of 13.  pH measurements conducted by
     DTSC's Project Team during on-site visits (using pH indicator paper with pH range 0-14)
     showed cleaning bath pH of 11 when using 10% 440-R SMT Detergent concentration.

  •   Worker Health and Safety: While using Smart Sonic Aqueous Cleaning Systems, Model
     2000 and 4200, end-users should follow Smart Sonic's recommended safety practices as
     outlined in the User's Manual and 440-R SMT Detergent Material Safety Data Sheet
     (MSDS).  The only significant toxicity associated with the 440-R SMT Detergent
     concentrate is acute toxicity due to its highly alkaline nature.  DTSC's Industrial Hygienist
     recommends end-users have an eye wash station and an MSDS available within close
     proximity to the cleaning systems.

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Results of the verification show that the Smart Sonic ultrasonic aqueous cleaning systems, Model
2000 and 4200, are capable of removing RMA (rosin mildly activated), no-clean, and water
washable solder pastes from printed circuit board stencils such that no solder paste remains in
stencil apertures at 10X magnification, provided that end-users follow Smart Sonic's cleaning
guidelines.  The Model 2000 and 4200 cleaning systems do not contain select volatile organic
compounds and halogenated compounds above detection limit of 0.01% (v/v) using SCAQMD's
CAS Certification Protocol (April 1997).  End-users should follow Smart Sonic's operational and
safety guidelines.

End-users should contact their stencil manufacturer prior to changing their cleaning process.
Changing from solvents to aqueous cleaning systems may require stencil modifications to make
the cleaning system and stencil compatible. In addition, the end-user should contact his/her local,
state, or federal regulatory authority regarding management of spent hazardous wastes generated
from use of the Smart Sonic aqueous cleaning systems (i.e.,  spent cleaning baths, rinse baths, and
solids containing lead).

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                                       Section 1.
                                     Introduction

Stencils are used in the printed circuit board industry to apply a solder paste pattern onto surface
mounted circuit boards (termed "printing"). Electronic components are then mounted to the
circuit board in the solder paste areas.  Following the assembly of components, the circuit board is
processed in the reflow oven in which the solder melts and forms the solder joint. After printing,
the stencil is cleaned to remove residual solder paste and is stored for a future print run.  It is
important to clean the stencil thoroughly so as to not cause misprints in future print runs. A
description of printed circuit board stencils and types of solder pastes is provided in Figure 1-1.

Background

Solvents used to clean solder paste from printed circuit board stencils include 1,1,2-trichloro-
1,2,2-trifluoroethane (CFC-113), 1,1,1-trichloroethane (1,1,1-TCA) and isopropyl alcohol (IPA).
The production of chlorinated solvents CFC-113 and 1,1,1-TCA have been banned as of January
1,1996 (Title VI of the Clean Air Act Amendments) because these solvents contribute to
stratospheric ozone depletion and global warming. Stockpiled chlorinated solvents are still used.
At present, they account for less than 5 percent of total use (estimate by Smart Sonic
Corporation).

Folio whig the production ban of CFC-113 and 1,1,1 -TC A, businesses began switching to
alternative solvents such as IP A, but IPA contributes to tropospheric smog and therefore is
considered a VOC. Use of CFC-113, 1,1,1-TCA, and IPA also generates hazardous waste and
poses a potential threat to worker health and safely.

Smart Sonic Technology

Smart Sonic Corporation developed ultrasonic aqueous cleaning systems to replace CFC-113,
1,1,1-TCA, and IPA-based systems for removing solder paste from printed circuit board stencils.

General Consideration

The Smart Sonic aqueous cleaning technology was originally accepted into the US EPA's
verification program as a pollution prevention technology due to its potential to reduce or
eliminate the use of smog and ozone depleting chemicals and for its potential to reduce hazardous
waste generation.  In general, the conversion to aqueous cleaners has minimized the impact to air,
but it is still uncertain how this conversion affects water and land. Unlike solvents that were
typically recycled off-site and returned to the business, aqueous cleaners, once spent, require
treatment either on-site or off-site. The aqueous cleaners are then discharged to a wastewater
treatment facility where they are further treated and discharged to a local body of water. There
are no studies to date that show the impacts of aqueous cleaners on all environmental media. A
more thorough analysis is needed to compare the impacts of aqueous cleaners versus organic
solvents before claims of pollution prevention can be substantiated.
       'Howard H. Manko, Soldering Handbook for Printed Circuits and Surface Mounting, Second Edition

                                            5

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               PCB Stencil
Solder Paste Printing
                                              Stencil
                                            Aperatures


                                             Stencil -
       Squeege
       .Blade
              Solder Paste
                                                       Printed Circuit Board
Frame   Glue Joints      Mesh
     Stencils

     Printed circuit board stencils are usually made up of different materials.  The frame is
     aluminum, the screen is either stainless steel or polyester, and the stencil is either stainless
     steel, brass, or nickel.  The stencil is bonded to the mesh via an adhesive. The mesh is also
     bonded to the frame via an adhesive.

     Solder Pastes'

     Solder paste consists of a powdered solder (typically a tin/lead powdered alloy) suspended in
     a flux base and a suitable vehicle. The flux base consists of rosin, resin, or a water soluble
     ingredient.  Another component of the flux system is the active ingredients which give the flux
     its chemical strength.  The vehicle and plasticizer are needed to give the material its
     consistency, suitable for screening.  There are several types of solder pastes that are used in
     PCB printing operations. These include Rosin Moderately Activated (RMA), No-Clean, and
     Water Washable. The main distinction between these solder pastes are the type affluxes used.

     Rosin Mildly Activated (RMA) - made of a variety of natural and modified rosins.  These fluxes
     contain a number of chemical additives called activators to give the flux more chemical
     strength for tarnish removal.

     No-Clean - resin and synthetic based fluxes which are an extension to the rosin based fluxes.
     These fluxes are very low solid content formulations and are designed to be left on the PCB
     board without adding any detrimental residues.

     Water Washable - nonrosin organic based fluxes.  These fluxes can range in strength (i.e.,
     tarnish removal, cleaning action) and are water soluble.
Figure 1-1. Description of PCB stencil and solder paste types.

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This verification will not make reference to pollution prevention and therefore will not attempt to
compare Smart Sonic's aqueous cleaning technology to that of other CFC-113,1,1,1-TCA, and
IPA-based cleaning systems.

                                       Section 2.
                              Description of Technology

Smart Sonic Corporation's stencil cleaning systems consist of Smart Sonic's 440-R SMT
Detergent, ultrasonic generator with 40 kHz piezoelectric transducers, stainless steel wash tank,
rinse tank (included in the semi-automated system), and control devices. Smart Sonic's stencil
cleaning systems evaluated in this project include the semi-automated Model 2000 and automated
Model 4200 shown in Figures ES-1 and 2-1. The semi-automated Model 2000 system is
approximately 3 feet high with a 40 x 44 inch base. This system has a wash tank and a separate
rinse station. System operations include preparing the initial wash bath, manually lowering the
stencil in the wash tank, setting the wash cycle timer (cleaning time) and pressing the start button,
manually removing the stencil from the wash tank after  completion of the wash cycle, rinsing the
stencil in a separate rinse tank using a hand-held spray nozzle (supplied with system), and drying
the stencil using dry compressed air or allowing to air dry.

The automated Model 4200 system is approximately 50 inches high with a 36x62 inch base. A
pneumatic lift, used to raise and lower the stencil in the wash bath, extends 36 inches for a total
system height of 86 inches. This system has one tank for washing with an automated rinse over
the wash tank. System operations include preparing the initial wash bath, loading the stencil into
the pneumatic lift, setting the wash cycle timer (ultrasonic time) and pressing two start buttons
(safety feature used to keep hands clear of pneumatic lift), and drying the stencil using dry
compressed air or allowing to air dry. The automated functions include raising and lowering the
stencil into the wash bath, cleaning the stencil to the preset wash time, and rinsing the stencil
using an automated rinse over the wash bath. The volume of rinse water used is predetermined by
the speed of the pneumatic lift during its opening cycle.

A feature of both systems are indicator lights and alarms to indicate either a low and/or high level
condition in the wash tank.  There are also several options for each system such as a power drain
to pump the  spent wash bath and rinses from the tanks for further waste management, a heater for
cleaning applications requiring higher solution temperatures, and for the Model 4200 system an
optional auto fill button for filling the wash tank with water and detergent. A brochure on Smart
Sonic's stencil cleaning systems is provided in Appendix A.

The combination of Smart Sonic's 440-R SMT Detergent and ultrasonics enables the removal of
solder pastes from printed circuit board stencils. The detergent surfactants act as wetting agents
to saturate the solder paste layer that is left on the stencil surface (from solder paste printing
operation). The ultrasonics then produce an intense scrubbing action, through cavitation and
implosion of microscopic bubbles, that enhances removal of the saturated solder paste layer.
Ultrasonics are often more effective in cleaning hard-to-reach surfaces (i.e., small stencil
apertures) than brushes and hand wipes.  The cleaning bath is operated at room temperature,
eliminating any potential effects to stencil from cleaning solutions requiring higher temperatures.

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                                    Model 2000

          440-SMT Detergent (s*10% Concentration)
                 Deionized or Soft Water
        Cleaning Bath Operated at Room Temperature
                Cleaning Time 60-90 Seconds
                   Cleaning Bath pH^ll
Deionized or Soft Water
                   Ultrasonic (40 fcHs)
                     Cleaning Bath
                                                    Manual Spray
                                                        Rinse
                                        Model 4200
          440-SMT Detergent («10% Concentration)
                  Deionized or Soft Water
        Cleaning Bath Operated at Room Temperature
                Cleaning Time 60-90 Seconds
                   Cleaning Bath pH«ll
      Deionized or Soft Water
                               Automatic Spray Rinse
                                                                          Overflow
Figure 2-1. Smart Sonic cleaning system operating parameters.

                                           8

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                                     Section 3.
                         Verification Activities and Results

 3.1  Laboratory Testing Conducted by DTSC Project Team

 DTSC's Project Team conducted VOC analyses, metals analyses, and pH measurements of two
 440-R SMT Detergent samples. The purpose of this activity was to:

   • determine if the 440-R SMT Detergent contains VOCs or halogenated compounds using the
     SCAQMD's CAS Protocol; and
   • identify any metals which may pose a potential health and safety or environmental problem.

 DTSC's Project Team obtained a third sample from an end-user which was spiked with known
 compounds and concentrations in order to determine the accuracy of SCAQMD's test method.
 DTSC and US EPA Project team selected four compounds, one from each of the four functional
 groups of compounds used in SCAQMD's calibration standards. The four functional groups
 include oxygenated organic compounds,  hydrocarbon compounds, aromatic compounds, and
 chlorinated compounds. The selected compounds include 2-butanone, octane, toluene, and
 carbon tetrachloride. The sample was spiked with approximately 1% of each compound.
 Currently, SCAQMD's CAS Protocol does not require a spiking of samples.

 3.1.1    Sampling of Smart Sonic 440-R SMT Detergent (Concentrate)

 DTSC's Project Manager and two Project Team members sampled two sites on May 28,1998. A
 500 ml detergent sample from each site was transported to DTSC's HML in Southern California
 for metals analyses and pH measurements. A 1000 ml detergent sample from each site was
 transported to SCAQMD laboratory for VOC analyses. In addition, a 100 ml detergent sample
 was taken from one of the sites and transported to SCAQMD laboratory for spiked sample
 analyses. All samples were drawn from unopened 5-gallon containers. A trip report identifying
 the sites, contacts, team member roles, and sampling activity is provided in
 Appendix B.

 3.1.2     Results of VOC Analyses

 SCAQMD conducted VOC analyses of the two 440-R SMT Detergent concentrate samples using
 SCAQMD's CAS Certification Protocol (CAS Protocol requires SCAQMD to use SCAQMD's
 Test Method 313  "Determination of Volatile Organic Compounds by GC/MS ".  SCAQMD
 evaluated the GC/MS data for the presence of Volatile Organic Hazardous Air Pollutants
 (VOHAPs), Ozone Depleting Compounds (ODCs), and Global Warming Compounds (GWCs).
 Results of VOC analyses are shown in Table 3-1. The list of VOHAPs, ODCs, and GWCs
targeted in SCAQMD's CAS Protocol  is provided in Tables 3-3, 3-4, and 3-5.  SCAQMD's
laboratory reports are provided in Appendix C.

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Table 3-1. Results of SCAQMD's VOC Analyses
SCAQMD Test Method 313
Sample 1
Sample 2
VOHAPs
Non-Detect
Non-Detect
ODCs
Non-Detect
Non-Detect
GWCs
Non-Detect
Non-Detect
In both samples, the GC indicated two peaks that SCAQMD further evaluated using mass
spectrometry. One of the compounds was tentatively identified as heptane, 2,4-dimethyl. The
second compound was identified as "unknown." Based on semi-quantitative calculations, the
concentrations of these two compounds would not exceed the SCAQMD limits to cause concern.
Overall results indicate that both end-user samples of 440-R SMT Detergent showed no detection
[0.01% (v/v) detection limit] of VOCs or halogenated compounds.

SCAQMD's spiked sample QA/QC results, shown in Table 3-2, indicated that recovery of spiked
compounds were well within the 75% - 125% requirement.

Table 3-2. Results of SCAQMD's Spiked Sample Recovery Analyses
Spiked Compound
n-Octane
2-Butanone
Toluene
Carbon Tetrachloride
% Recovery
102.2
98.49
97.42
93.08
During review of the VOC analyses, DTSC's Project Manager found a discrepancy between the
GC/MS calibration procedure used during the SCAQMD testing and the GC/MS calibration
procedure outlined hi the CAS Protocol. The CAS Protocol requires a multi-level calibration
using .1,1,10, and 25 g/L standards. Prior to testing Smart Sonic's 440-R SMT Detergent
samples, a single-point calibration of the GC/MS was performed. This results in a single-point
calibration response factor instead of an average response factor that would be obtained from a
multi-level calibration.  Calibration checks using 25 g/L standards showed that target analytes
were within ±25% of the single-point calibration response factor.
                                          10

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Table 3-3. SCAQMD Targeted Hazardous Air Pollutants
  CAS
NUMBER
 75070
 0355
 75058
 98862
 53963
 107028
 79061
 79107
 107131
 107051
 92671
 62533
 90040
 1332214
 71432

 92875
 98077
 100447
 92524
 117817

 542881
 75252
 106990
 156627
 105602
 133062
 63252
 75150
 56235
 463581
 120809
 133904
 57749
 7782505
 79118
 532274
 108907
 510156
 67663
 107302
 CHEMICAL NAME

 Acetaldehyde
 Acetamide
 Acetonitrile
 Acetophenone
 2-Acetylaminofluorene
 Acrolein
 Acrylamide
 Acrylic acid
 Acrylonitrile
 Allyl chloride
 4-Aminobiphenyl
 Aniline
 o-Anisidine
 Asbestos
 Benzene (including
 benzene from gasoline)
 Benzidine
 Benzotrichloride
 Benzyl chloride
 Biphenyl
 Bis(2-ethylhexyl)phthalate
 (DEHP)
 Bis(chloromethyl)ether
 Bromoform
 1,3-Butadiene
 Calcium cyanamide
 Caprolactam
 Captan
 Carbaryl
 Carbon disulfide
 Carbon tetrachloride
 Carbonyl sulflde
 Catechol
 Chloramben
 Chlordane
 Chlorine
 Chloroacetic acid
2-Chloroacetophenone
Chlorobenzene
Chlorobenzilate
Chloroform
Chloromethyl methyl ether
  CAS
 NUMBER      CHEMICAL NAME

 126998         Chloroprene
 1319773        Cresols/Cresylic acid (isomers
                and mixture)
 95487          o-Cresol
 108394         m-Cresol
 106445         p-Cresol
 98828          Cumene
 94757          2,4-D, salts and esters
 3547044        DDE
 334883         Diazomethane
 132649         Dibenzofurans
 96128          l,2-Dibromo-3-chloropropane
 84742          Dibutylphtalate
 106467         l,4-Dichlorobenzene(p)
 91941          3,3-Dichlorobenzidene
 111444         Dichloroethyl ether
                (Bis(2-chloroethyl)ether)
 542756         1,3-Dichloropropene
 62737          Dichlorvos
 111 422        Diethanolamine
 121697        N,N-Diethyl aniline (N,N-
               Dimethylaniline)
 64675         Diethyl sulfate
 119904        3,3-Dimethoxybenzidine
 60117         Dimethyl aminoazobenzene
 119937        3,3-Dimethyl benzidine
 79447         Dimethyl carbamoyl chloride
 68122         Dimethyl formamide
 57147          1,1 -Dimethyl hydrazine
 131113        Dimethyl phthalate
77781          Dimethyl sulfate
534521         4,6-Dinitro-o-cresol, and salts
51285          2,4-Dinitrophenol
 121142        2,4-Dinitrotoluene
 123911         1,4-Dioxane
               (1,4-Diethylene oxide)
 122667        1,2-Diphenylhydrazine
106898         Epichlorohydrin
               (l-Chloro-2, 3-epoxypropane)
106887         1,2-Epoxybutane
140885         Ethyl acrylate
100414         Ethyl benzene
                                            11

-------
Table 3-3. Continued
  CAS                                             CAS
NUMBER     CHEMICAL NAME             NUMBER
 51796        Ethyl carbamate (Urethane)           108101

 75003         Ethyl chloride (Chloroethane)         624839
 106934        Ethylene dibromide                 80626
               (Dibromoethane)                    1634044
107062         Ethylene dichloride                 101144
               (1,2-Dichloroethane)
 107211        Ethylene glycol                     75092
 151564        Ethylene imine (Aziridine)
 75218         Ethylene oxide                      101688

 96457         Ethylene thiourea
 75343         Ethylidene dichloride                101779
               (1,1 -Dichloroethane)                91203
 50000         Fomaldehyde                       98953
 76448         Heptachlor                        92933
 118741        Hexachlorobenzene                 100027
 87683         Hexachlorobutadiene                79469
 77474         Hexachlorocyclopentadiene           684935
 67721         Hexachloroethane                   62759
 822060        Hexamethylene-1,6-                 59892
               diisocyanate                       56382
 680319        Hexamethylphosphoramide           82688
 110543        Hexane
 302012        Hydrazine                         87865
 7647010      Hydrochloric acid                   108952
 7664393      Hydrogen fluoride                   106503
               (Hydrofluoric acid)                 75445
 7783064      Hydrogen sulfide                   7803512
 123319        Hydroquinone                      7723140
 78591         Isophorone                        85449
 58899         Lindane (all isomers)                1336363
 108316        Maleic anhydride
 67561         Methanol                          1120714
 72435         Methoxychlor                      57578
 74839         Methyl bromide                    123386
               (Bromomethane)                    114261
 74873         Methyl chloride                    78875
               (Chloromethane)
 71556         Methyl chloroform                 75569
                (1, 1,1 -Trichloroethane)            75558
 78933         Methyl ethyl ketone (2-Butanone)
 60344        Methyl hydrazine                   91225
 74884        Methyl iodide (lodomethane)         106514
CHEMICAL NAME

Methyl isobutyl ketone
(Hexone)
Methyl isocyanate
Methyl methacrylate
Methyl tert butyl ether
4,4-Methylene bis (2-chloro-
aniline)
Methylene chloride
(Dichloromethane)
Methylene diphenyl
diisocyanate (MDI)

4,4-Methylenedianiline
Naphthalene
Nitrobenzene
4-Nitrobiphenyl
4-Nitorphenol
2-Nitropropane
N-Nitroso-N-methylurea
N-Nitrosodimethylamine
N-Nitrosomorpholine
Parathion
Pentachloronitrobenzene
(Quintobenzene)
Pentachlorophenol
Phenol
p-Phenylenediamine
Phosgene
Phosphine
Phosphorus
Phthalic anhydride
Polychlorinated biphenyls
(Aroclors)
1,3-Propane sultone
beta-Propiolactone
Propionaldehyde
Propoxur (Baygon)
Propylene dichloride
 (1,2-Dichloropropane)
Propylene oxide
1,2-Propylenimine (2-Methyl
aziridine)
Quinoline
Quinoline	
                                             12

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 Table 3-3. Continued
  CAS
 NUMBER
  100425
  96093
  1746016

  79345
  127184

  7550450
  108883
  95807
  584849
  95534
  8001352

  120821
  79005
  79016
  95954
  88062
  121448
  1582098
  540841
  108054
  593602
  75014
CHEMICAL NAME

Styrene
Styrene oxide
2,3,7,8-Tetrachlorodibenzo-
p-dioxin
1,1,2,2-Tetrachlorethane
Tetrachloroethylene
 (Perchloroethylene)
Titanium tetrachloride
Toluene
2,4-Toluene diamine
2,4-Toluene diisocyanate
o-Toluidine
Toxaphene (chlorinated
camphene)
1,2,4-Trichlorobenzene
1,1,2-Trichloroethane
Trichloroethylene
2,45-Trichlorophenol
2,4,6-Trichlorophenol
Triethylamine
Trifluralin
2,2,4-Trimethylpentane
Vinyl acetate
Vinyl bromide
Vinyl chloride
  CAS
NUMBER     CHEMICAL NAME

75354          Vinylidene chloride
                (1,1 -Dichloroethylene)
1330207        Xylenes (isomers and mixture)
95476          o-Xylenes
108383         m-Xylenes
106423         p-Xylenes
0               Antimony Compounds
0               Arsenic Compounds (inorganic
                including arsine)
0               Beryllium Compounds
0               Cadmium Compounds
0               Chromium Compounds
0               Cobalt Compounds
0               Coke Oven Emissions
0               Cyanide Compounds1
0               Glycol ethers2
0               Lead Compound
0               Manganese Compounds
0               Mercury Compounds
0               Fine mineral fibers3
0               Nickel Compounds
0            .   Polycyclic Organic Matter"
0               Radionuclides (including
                radon)5
0               Selenium Compounds
Note: For all listings above which contain the word "compounds" and for glycol ethers, the following applies: Unless
     otherwise specified, these listings are defined as including any unique chemical substance that contains the namec
     chemical (i.e.,antimony, arsenic, etc.) as part of that chemical's infrastructure.
 X'CN where X=H' or any other group where a formal dissociation may occur. For example KCN or Ca(CNJ

2 Includes mono- and di-ethers of ethylene glycol, diethylene glycol, and triethylene glycol R(OCH2CH?)OR'
 where
     n=l,2, or 3
     R=alkyl or aryl groups
     R'= R, H, or groups which, when removed, yield glycol ethers with the structure:
         R(OCH2CH)n-OH. Polymers are excluded from the glycol category.

3 Includes mineral fiber emissions from facilities manufacturing or processing glass, rock or slag fibers (or other
 mineral derived fibers) of average diameter 1 micrometer or less.

4 Includes organic compounds with more than one benzene ring, and which have a boiling point greater than or equal to
 100°C.

5 A type of atom which spontaneously undergoes radioactive decay.
                                               13

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Table 3-4. SCAQMD Targeted Ozone Depleting Compounds
Class I
Group I:
CFC-11
CFC-12
CFC-11 3
CFC-114
CFC-1 15




Group U:
Halon-1211
Halon-1301
Halon-2402
All isomers of the
above chemicals

Group III:
CFC-1 3
CFC-1 1 1
CFC-1 12
CFC-211
CFC-212
CFC-213
CFC-214
CFC-215
CFC-216
All isomers of the
above chemicals

Group VI:
Carbon Tetrachloride

Group V:
1,1,1 -Trichloroethane
(Methyl Chloroform)
All isomers of the
above chemical
except 1,1,2-
Trichloroethane

Group VI:
Methyl Bromide

Group VII:
HBFC-22B1
All isomers of the
above chemical











Class 11

HCFC-21
HCFC-22
HCFC-31
HCFC-121
HCFC-122
HCFC-123
HCFC-124
HCFC-131
HCFC-132b
HCFC-133a
HCFC-141b
HCFC-142b
HCFC-22 1
HCFC-222
HCFC-223
HCFC-224
HCFC-225ca
HCFC-225cb












HCFC-226
HCFC-231
HCFC-232
HCFC-233
HCFC-234
HCFC-235
HCFC-241
HCFC-242
HCFC-243
HCFC-244
HCFC-251
HCFC-252
HCFC-253
HCFC-261
HCFC-262
HCFC-271
All isomers
of the above
chemicals









                                   14

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Table 3-5. SCAQMD Targeted Compounds With Global Warming PQtential
             CO2

             Methane
             Nitrous Oxide

             HFC=23
             HFO32
             HFC-41
             HFC-43-10mee
             HFC-125
             HFC-134
             HFC434a
             HFC152a
             HFC-143
             HFC443a
             HFC-227ea
             HFC-236fa
             HFC-245ca

             Sulphur hexafluoride
             Perfluoromethane
             Perflouroethane
             Perfhioropropane
             Perfluorpbutane
             Perfluorocyclobutane
             Perfluoropentane
             Perfluorohexane
CFCM1
CFC-12
CFC.13
CFC413
CFC-114
CFC-115
Halon.l3Ql
Carbon Tetrachloricie
Methyl Chloroform
HCFC-22
HCFC-Hlb
HCFC-124
HCFC-223ca
HCFC-225cb
                                      15

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3.1.3     Results of Metals Analyses
DTSC's HML conducted metals analyses of the two 440-R SMT Detergent concentrate samples.
Results of metals analyses are shown in Table 3-6. The laboratory report provided by HML is
provided in Appendix D. Overall results indicate that both end-user samples of 440-R SMT
Detergent concentrate showed no detection of metals.
Table 3-6. Results of DTSC's HML Metals Analyses

         Analytical Procedures Used:   Digestion:
                                     Analysis:
EPA SW 846 Method 3050B
EPA SW 846 Method 601 OB
Metal
Silver
Arsenic
Barium
Beryllium
Cadmium
Cobalt
Chromium
Copper
Molybdenum
Nickel
Lead
Antimony
Selenium
Thallium
Vanadium
Zinc
Detection Limit
(mg/kg)
1.0
1.0
1.0
0.10
0.10
1.0
1.0
1.0
1.0
1.0
1.0
1.0
0.20
1.0
1.0
1.0
Sample 1
<1
<1
<1
<.l
<.l
<1
<1
<1
<1
<1
<1
<1
<.2
<1
<1
<1
Sample 2
<1
<1
<1
<.l
<.l
<1
<1
<1
<1
<1
<1
<1
<.2
<1
<1
<1
                                          16

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 Table 3-6. Continued
          Analytical Procedure Used:   Hg Method 7470A (Manual Cold Vapour Technique)
Metal
Mercury
Detection Limit
(mcg/gm)
0.02
Sample 1
O.02
Sample 2
O.02
 3.1.4     Results of pH Measurement

 DTSC's HML conducted pH measurements of the two 440-R SMT Detergent concentrate
 samples. Results of the pH measurements are shown in Table 3-7.  Results indicated a
 concentrate pH of 13. NOTE: The 440-R SMT Detergent MSDS provided by Smart Sonic states
 a pH of 12.4.

 Table 3-7. Results of DTSC's HML pH Measurements

                  Analytical Procedure Used:    pH EPA Method 9045C

pH at 23 °C
Sample 1
13.0
Sample 2
13.0
3.2  End-User Data Collection

DTSC's Project Manager contacted, by phone, Smart Sonic end-users and gathered data in the
following areas:

   • process parameters (bath characteristics, stencil size, solder paste type);
   • performance (cleaning, maintenance);
   • waste generation rates and management; and
   • overall satisfaction.

The purpose of the phone questionnaires was to:

   • provide supportive information to the evaluation of this technology; and
   • develop a database of information from which to select end-users for on-site visits.

A list of end-users was provided by Smart Sonic in July, 1997 and then updated by Smart Sonic in
June, 1998. DTSC's Project Team then contacted two end-users of each system type (Model
2000, Model 4200)  followed by type of solder paste cleaned (RMA, no-clean, and water soluble).
For instance, two end-users using a Model 2000 cleaning system to remove RMA solder paste
from printed circuit board stencils were contacted. Another two end-users using the Model 2000
cleaning system to remove no-clean solder paste were also contacted.
                                          17

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DTSC's Project Manager contacted 61 facilities (37 facilities were contacted via voice mail,
questionnaires were sent to 8 facilities via facsimile, and 16 facilities were sent questionnaires via
e-mail). Follow-up calls and e-mails were directed at some of the facilities to increase response
rate.

A total of 12 completed questionnaires were received, a response rate of approximately 20%.
Two end-users have been using de-ionized (DI) water as the cleaning solution and one end-user
recently changed to DI water instead of the Smart Sonic 440-R SMT Detergent solution.  DI
water can be used to remove water soluble solder paste from stencils. This report will not use any
data provided by end-users of DI water cleaning solutions since this evaluation addresses the
performance of Smart Sonic cleaning systems which includes the cleaning equipment and 440-R
SMT Detergent cleaning solution. Table 3-8 provides a summary of the number and type of end-
users that responded to the questionnaires.

Table 3-8. Number and Type of End-User Questionnaire Responses

Cleaning System
Model 2000
Model 4200
Solder Paste Type
RMA
2
1
No-Clean
2
1
Water Washable
4
0
Note:     There was a total of 9 responses with one end-user cleaning both no-clean and water
          washable pastes.

As shown in Table 3-8, four additional end-user responses were needed to fulfill the phone
questionnaire requirements i.e., two end-users of each system type and solder paste type. This
requirement was established to allow some flexibility and choice in selecting end-users for on-site
performance validation (Section 3.3). The lack of phone responses was not critical in that
DTSC's Project Team located other facilities, from a previous phone inquiry of Smart Sonic end-
users, that could fulfill the on-site performance validation activity.

Original questionnaire responses are provided in Appendix E. Facilities that provided incomplete
or unclear responses were contacted a second time via phone. A summary of the questionnaires,
identifying key responses, is shown in Appendix F.
                                            18

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3.2.1     Summary of End-User Data

The following is a brief summary of questionnaire responses:

Cleanliness: All respondents (total of 9) were satisfied with the Smart Sonic stencil cleaning
systems and stated that the systems clean consistently and as good, if not better s than the
previously used cleaning system (most commonly used cleaning method was alcohol and wipes).
Cleaning bath concentrations ranged from 5-15 % by volume of Smart Sonic's 440-R SMT
Detergent concentrate.  The size of stencils cleaned were 8 mil pitch or greater. Respondents did
not indicate any standards or specifications for measuring cleanliness but stated that  PCB stencils
are visually inspected for solder paste residue. Most facilities pre-wipe stencils (i.e.,  remove
excess solder paste) prior to cleaning in the Smart Sonic systems.

Waste Generation: The amount of spent cleaning solution generated from the Model  2000
cleaning systems ranged from 20-25 gallons per week to 20-25 gallons per month. The amount of
spent cleaning solution generated from the Model 4200 cleaning systems ranged from 50 gallons
per week to 50 gallons per 2 weeks. The waste generation figures given above do not include the
amount of rinse water or solids that are generated from the cleaning systems. Although the
Systems Information Manual provided by Smart Sonic recommends that the cleaning bath be
changed every week, respondents indicated that the bath change-out time varied from weekly to
monthly.

Waste Characterization and Waste Management: Two of the nine respondents analyzed their
spent cleaning solutions as having hazardous waste characteristics (results were not available).
None of the other respondents analyzed their spent cleaning solutions for hazardous
characteristics. Eight of nine respondents are managing their spent cleaning solutions and rinse
waters through evaporation with the ninth respondent treating its aqueous waste on-site.  Most
end-users that evaporate the spent aqueous solutions are not characterizing the spent cleaning
solution prior to evaporation.  The residue from  evaporation, however, is assumed hazardous and
is managed as hazardous waste.  Solids generated in the cleaning bath (mainly tin-lead fall-out
from solder paste) are managed as hazardous waste.

Maintenance: None of the questionnaire responses indicated any maintenance problems from
using the Smart Sonic cleaning system. Cleaning systems have been in place from as little as 3
months up to 3 years. Some stencils have been subjected to as many as 300 cleaning cycles.

Stencil Issues: Four of the nine respondents claimed that the Smart Sonic cleaning system
removes/degrades the epoxy fiducials from some stencils.  Fiducial marks are used to visually
align the stencil to the printed circuit board prior to solder paste printing. DTSC's Project
Manager called stencil manufacturers to discuss the issue of fiducial removal/degradation.
                                           19

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Two causes for fiducial removal/degradation as stated by these manufacturers include:

  •   fiducial bonding area, approximately 1 mm in diameter and .002 inch deep, is very small
     which results hi a mechanical bond that is somewhat weak2'3'4; and
  •   fiducials may be dislodged during the solder paste printing process, especially if fiducials are
     located on the stencil surface that makes contact with the printing squeegee5.

Once the fiducial is removed/degraded, end-users remark the area with black permanent ink after
cleaning the stencil. None of the end-users stated that this problem effected production or
product quality.  One stencil manufacturer stated that they have overcome fiducial degradation
caused from aqueous cleaners by changing the type of epoxy used and how the epoxy is bonded
to the stencil3.

Two of the nine respondents claimed that some stencils have debonded from the screen. Stencils,
usually made of stainless steel, are bonded to a screen (stainless steel or polyester) via a
proprietary epoxy/glue.  All respondents stated that debonding occurred at the stencil/epoxy
interface. In speaking with stencil manufacturers, debonding can occur under the following
conditions:

   • high cleaning solution temperature (temperatures exceeding 125 to 130°F softens the
     epoxy/glue joinf/'7'8;
   • different contraction/expansion rates of the stainless steel stencil and epoxy/glue;
   • stress on epoxy/glue joint during printing operation (varies with image design*);
   • physical characteristic of epoxy/glue (i.e., rigidness, flexibility^9; and
   • pH of solution is greater than 126.

Three of the stencil manufacturers contacted stated that they had overcome the debonding
problem by using alternative epoxies that remain more flexible. Epoxies that are not as hard tend
to hold up better to the mechanical stresses that  are incurred during printing and cleaning
operations. All of the respondents that had debonding problems and switched to alternative
epoxies have had no reoccurrences of debonding.

One respondent claimed that the Smart Sonic detergent coupled with the ultrasonics separates
fine pitch stepped stencils. The stepped stencils started debonding after approximately  12
cleaning cycles. Stepped stencils (i.e., laminated stencils) are used to achieve different thicknesses
of solder paste throughout the print. These stencils consists of two sheets of stainless steel which
 2 Phone
 3 Phone
 4 Phone
 5 Phone
 6 Phone
 7 Phone
 8 Phone
 9 Phone
Conversation 7/30/98: Hybrid Integrated Services
Conversation 7/30/98: Photo Stencil Incorporated
Conversation 7/31/98: UTZ Engineering, Incorporated
Conversation 7/30/98: Electro Precision Incorporated
Conversation 7/30/98:1 Source
Conversation 7/30/98: Pela Tech
Conversation 7/8/98: AlphaSigma Stencils
Conversation 7/8/98 and 7/30/98; Electro Precision Incorporated
                                            20

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are bonded with an epoxy adhesive and then cured in an oven. DTSC's Project Manager
contacted the end-user's stencil manufacturer but it was not known what caused the debonding.
The end-user has cleaned other types of stencils (i.e., single sheet) in its Smart Sonic aqueous
cleaning system without any debonding problems.

Another respondent claimed that the emulsion used on the stencil screen is degraded by the Smart
Sonic cleaning system.  An emulsion is used on the screen as a block-out to prevent solder paste
from flowing through the screen, during the printing operation, and on to unwanted areas of the
printed circuit board. One of the stencil manufacturers who conducts business with many of
Smart Sonic end-users stated that their previous emulsions were being degraded by the Smart
Sonic cleaning systems, however, this emulsion was replaced by a proprietary emulsion and there
have been no other occurrences of emulsion degradation9.

3.3  On-Site Performance Validation

DTSC's Project Team visited end-users of Smart Sonic's cleaning systems to:

   •  validate cleaning performance i.e., no solder paste in stencil apertures at 10X magnification
     (each end-user must have had Smart Sonic cleaning system in operation for at least 6
     months); and
   •  gather additional process information and identify issues that merit further evaluation.

As mentioned in Section 3.2, DTSC's Project Manager received twelve phone questionnaires.
Out of the twelve questionnaires, nine respondents conditionally agreed to have DTSC's Project
Team conduct on-site visits. From these nine respondents, one respondent operated its bath with
water only and another respondent operated its bath above room temperature (higher temperature
solutions used to clean adhesives, inks, or built-up flux residues).  This left seven respondents for
potential on-site visits.  The following list represents the type of cleaning system used and type of
solder paste removed for the seven respondents.
     Model 2000
     Model 4200
RMA
  2
  1
no-clean
   0
   1
water washable
 '  "  '3	""
      0
As shown in the list above, two additional respondents were needed to complete the on-site
performance validation i.e., one respondent using the Model 2000 with no-clean solder paste and
one respondent using the Model 4200 with water washable solder paste.  To locate additional
end-users, DTSC's Project Manager:

   • contacted Smart Sonic for an updated list of end-users; and
   • reviewed a list of end-users that were contacted in a previous questionnaire conducted in
     August, 1997.

Given this additional information, the Project Manager identified the remaining end-users that
could be visited to complete the on-site performance validation. Unfortunately, there were not
enough end-users to justify a formal selection process. Therefore, DTSC's Project Manager
contacted end-users that agreed to a site-visit. The Project Manager focussed on end-users

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located in California because many of the end-users were grouped in two major areas in
California, thereby making it more feasible for on-site visits.

Five end-users were visited by DTSC's Project Team.  A site visit was scheduled with the sixth
and final end-user (Model 4200/RMA), but the end-user had scheduling conflicts and therefore
was not available. Table 3-9 represents the type of cleaning system used and type of solder paste
removed for the five end-users that were visited by DTSC's Project Team. Details of on-site
visits are provided in Appendix G.

Table 3-9. Number and Type of End-Users Visited by DTSC's Project Team

Model 2000
Model 4200
RMA
1
0
no-clean
1
1
water washable
1
1
3.3.1    Results of On-Site Performance Observations

Results of on-site observations and inspections are as follows:

   • In five facilities visited, DTSC's Project Team observed no solder paste in stencil apertures
     at 10X magnification. The size of stencil apertures ranged from 12-50 mil. All end-users
     removed excess solder paste from stencil prior to cleaning in the Smart Sonic cleaning
     systems. Cleaning times ranged from 60-90 seconds. Four of the five end-users visited were
     using a 10% concentration of Smart Sonic's 440-R SMT Detergent (10% concentration
     recommended by Smart Sonic). The other end-user was using a 5% detergent concentration
     for removing water washable paste. This 5% concentration is adequate because the flux in
     the solder paste is water soluble.

         At one facility (Model 4200/No-Clean), an operator pre-cleaned a stencil with alcohol
         wipes prior to final cleaning in the Smart Sonic system. After final cleaning, the DTSC
         Project Team detected a few solder balls hi one corner of a 50 mil stencil aperture
         (DTSC Project Manager estimated a blocked area of approximately 5%). DTSC's
         Project Manager discussed the finding with the president of Smart Sonic and learned
         that the operator was not following recommended cleaning practices. Smart Sonic
         states in its Operations Manual that "alcohol and other chemical wipes should be
         discouraged since they may react with the solder paste making it more difficult to
         remove." Smart Sonic's representative immediately informed the facility to not use
         alcohol prewipes.  DTSC's Project Team revisited this facility on December 4, 1998.
         DTSC's Project Team observed the facility cleaning a stencil using Smart Sonic's
         recommended cleaning practices.  The Project Team also conducted a cleanliness
         inspection of the stencil following the cleaning operation and found no solder paste in
         stencil apertures when observed using 10X magnification.

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      DTSC's Project Team was unable to visit a facility using a Model 4200 system to clean
      RMA solder paste due to an end-user scheduling conflict. DTSC's Project Team did,
      however, visit a facility using Smart Sonic's Model 2000 system to clean RMA solder
      paste and after observing a stencil cleaning operation found no solder paste in stencil
      apertures (20-50 mil) using 10X magnification.  The performance of the Model 4200
      system in cleaning RMA solder paste should be  similar to the Model 2000 system in
      cleaning RMA solder paste given that:

       •   Smart Sonic's recommended 10% 440-R SMT Detergent bath concentration is
          used; and
       •   Smart Sonic's recommended cleaning practices are followed.

      The Model 2000 and 4200 systems are very similar in that both systems use 40 kHz
      piezoelectric transducers and have equivalent ultrasonic power.  In addition, the stencil
      is located the same distance from the transducers in each system10. The only observed
      differences between the two  systems is that the Model 4200 system has several
      automated functions which include: raising and lowering  of the stencil into the wash
      bath, cleaning the stencil to the preset wash time, and rinsing the stencil using an
      automated rinse over the wash bath.

      As a final note, RMA solder paste is becoming the least used solder paste in the
      industry. The military and its contractors are the few remaining users of RMA solder
     pastes11
Two end-users stated that stencil separation had occurred. One end-user claimed that stencil
separation only occurred when the cleaning bath was heated to 140°F for cleaning epoxy.
The second end-user claimed that separation was caused by poor bonding of the stencil to
the screen at the manufacturer. DTSC's Project Manager contacted several stencil
manufacturers to discuss conditions which may cause stencils to separate. See Section
3.2.1, paragraph entitled "Stencil Issues" for a list of these conditions.

Stencils had been cleaned 20 to 1000 times in the Smart Sonic cleaning systems without
damage.

pH tests (using pH indicator paper with pH range 0-14) showed cleaning bath pH of 11
when using 10% 440-R SMT Detergent concentration.

Results of health and safety observations are discussed in Section 3.4.1.
  10 E-mail on November 4, 1998: President of Smart Sonic Corporation

  11 Phone Conversation 11/24/98: AIM (Solder Supplier)

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3.4  IH/lexicologist Review

A DTSCIH conducted a health and safety review of the following items to determine whether
conditions exist which may pose a hazard to worker safety:

   • a review of Smart Sonic's Systems Information Manual; and
   • observations of end-users operating Smart Sonic's cleaning systems.

A DTSC Toxicologist also conducted a review of the following items to determine whether
characteristics or conditions exist which may pose a hazard to public health and the environment.

   • Smart Sonic's 440-R SMT Detergent ingredients list (proprietary) and MSDSs; and
   • results of metals analyses conducted by DTSC's HML and VOC analyses conducted by
     SCAQMD's Laboratory.

3.4.1     Results of DTSC's IH and Toxicologist Review

A total of three different site visits were conducted by DTSC's IH; two facilities using the manual
Model 2000 cleaning system and one facility using the automated Model 4200 cleaning system.
DTSC's IH concluded that:

   • While using Smart Sonic Aqueous Cleaning Systems, Model 2000 and 4200, end-users
     should follow Smart Sonic's recommended safety practices as outlined in the Systems
     Information Manual and 440-R SMT Detergent MSDS. DTSC's IH also recommended that
     the end-user have an eye wash station located and a MSDS available within close proximity
     to  the cleaning systems.

The details of DTSC's IH review are shown in Appendix H (memorandum). Although the IH did
not review maintenance activities (i.e., preparing the detergent bath and initiating start-up
procedures; removing and managing spent detergent solution and tank bottoms), DTSC's Project
Manager identified further safety precautions through review of the Systems Information Manual.
The following is a list of activities and proposed safety practices:

    • Loading 440-R SMT Detergent into cleaning bath - wear eye protection, gloves, and
     appropriate clothing as stated in detergent MSDS;
    • "Degassing" detergent solution (to remove dissolved air from cleaning bath) can cause an
     extremely loud squeal for a short duration- use appropriate ear protection.
    • Removing stencil from Model 2000 detergent bath - be aware that when stencils are lifted
     above waist height, detergent solution may drip down gloves and contact skin or clothing.
     Protective clothing should be worn to prevent skin contact.
    • Removing lead-bearing sludge from bottom of cleaning tank/drain trap and wiping down
     cleaning tank - wear appropriate protection to prevent contact with lead.
                                           24

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DTSC's toxicologist concluded that the only significant toxicity associated with the 440-R SMT
Detergent concentrate would be acute toxicity due to its highly alkaline nature. DTSC's
Toxicologist review is shown in Appendix I (memorandum).

     Note:     Smart Sonic's 440-R SMT Detergent ingredients are proprietary and are not
              shown in this report or its appendices.

                                     Section 4.
            Review Existing Analytical Data Provided by SCAQMD

DTSC's Project Team reviewed existing analytical data provided by the SCAQMD.

     Note: This existing data was not independent data collected by DTSC's Project Team;
     nonetheless, the data provides supportive information to the VOC analyses conducted by
     DTSC's Project Team as part of this verification (Section 3).

In September of 1997, Smart Sonic submitted a sample of 440-R SMT Detergent to SCAQMD
for VOC analyses using SCAQMD's CAS Protocol (April 1997). The VOC analyses were
conducted by SCAQMD on October 14, 1997.  SCAQMD's laboratory report (Appendix J) was
reviewed by DTSC's Project Team and compared to the product ingredient list supplied by Smart
Sonic.

DTSC Project Team's review revealed that Smart Sonic's 440-R SMT Detergent (concentrate)
contained 0.1% methanol which is ten times greater than the detection limit stated in the CAS
Protocol. DTSC's Project Team Manager collaborated with SCAQMD about the findings and
SCAQMD in turn informed Smart Sonic that the 440-R SMT Detergent did not currently meet
the CAS Protocol.

Smart Sonic consulted with its "blender" (contractor who manufactures the 440-R SMT
Detergent for Smart Sonic) to determine why methanol was used in the 440-R SMT Detergent
formulation. Smart Sonic stated that the "blender" substituted a prior ingredient with methanol
without informing Smart Sonic of the change.

SCAQMD requested Smart Sonic to change its formulation or reduce the methanol concentration
to bring the 440-R SMT Detergent within the limits of the CAS Protocol.  Smart Sonic
reformulated its 440-R SMT Detergent with a non-methanol ingredient (440-R SMT Detergent
ingredients are proprietary). On March 18, 1998, Smart Sonic submitted a sample of its
reformulated 440-R SMT Detergent (concentrate) to SCAQMD for VOC analyses.  The VOC
analyses of the reformulated 440-R SMT Detergent were conducted by SCAQMD on March 26,
1998. SCAQMD determined that the reformulated 440-R SMT Detergent passed the  CAS
Protocol (Appendix K).

Manufacturing lot numbers at or above the Lot Number Q8089412 contained the reformulated
440-R SMT Detergent. DTSC's laboratory analyses in Section 3 were conducted using samples
from lot numbers Q8089412 and Q8089416.
                                         25

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                                      Section 5.
         Hazardous Waste Management / Hazardous Waste Regulations

As with most types of cleaning systems, Smart Sonic's aqueous cleaning systems will also
generate wastes that will require some form of management, depending on the characteristics of
the wastes. Generators of wastes are required to determine whether the wastes meet the
characteristics of a hazardous waste as identified hi Part 261, Title 40 of the US Code of Federal
Regulations (40 CFR 261) or hi Section 66261, Chapter 11, Title 22 of the California Code of
Regulations (22 CCR §66261).  If wastes are identified as hazardous wastes, these wastes must
be managed in accordance to federal, state, or local regulations. On-site treatment of hazardous
wastes may also require a permit, and generators must contact their regulatory authority prior to
treating hazardous wastes. Hazardous wastes will generally require a licensed hazardous waste
hauler for transporting.

The US EPA and DTSC encourages pollution prevention, reuse, and recycling to eliminate or
further reduce the quantity of generated hazardous waste. As with any direct or indirect
manufacturing process there is potential for further waste reduction.  Some common waste
reduction options include:

   •  extending bath life (i.e., filtration);
   •  reuse of spent materials hi manufacturing process (i.e., rinse water, metals);
   •  recycling of spent materials through ion exchange, filtration, and in some instances
     evaporation.

As stated above, use of several of these techniques may require a permit if the waste is
characterized as being hazardous (considered treatment of a hazardous waste). If however, by
using one of these management techniques a material is recycled back into the cleaning process or
manufacturing process, this activity may be exempt from permitting. Again, generators must
contact their regulatory authority for a permitting determination.

                                      Section 6.
                                Vendor's Comments

The following information was provided by Smart Sonic. The purpose is to provide the vendor
with the opportunity to share additional information on their technology. This information does
not reflect agreement or approval by  the US EPA and Cal/EPA.

Systems Costs - As of the printing  of this Report, the baseline costs of the Model 2000 and
Model 4200 systems are $20,000 and $35,000 respectively.  The price of the 440-R SMT
Detergent® is $19.80 per gallon in 5 gallon pails and $18.00 per gallon in 55 gallon drums.

440-R SMT Detergent - As with any cleaning process, the most important feature is the
chemistry. Unlike saponifiers that are consumed during the cleaning process and require
continuous replenishment, Smart Sonic's 440-R SMT Detergent is a surfactant (wetting agent)
that is not consumed or "loaded" when cleaning solder paste. In addition, saponifiers operate at
                                          26

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elevated temperatures whereas Smart Sonic's 440-R SMT Detergent operates at ambient
temperature.  Therefore, chemistry and energy consumption is a fraction of that of a system using
a saponifier chemistry.

Waste Management - Because 440-R SMT Detergent is not consumed during the cleaning
process, the wash solution need only be changed one time per week independent of the number of
stencils cleaned, so wastewater generation is limited.  While 440-R SMT Detergent can be filtered
by conventional means and prepared for drain disposal like other aqueous waste streams, 440-R
SMT Detergent also provides the flexibility of routine evaporation of associated wastewater.
Because 440-R SMT Detergent contains no hazardous ingredients, no VOCs and the pH is mild
alkaline, the resulting wastewater can simply and safely be evaporated to the atmosphere in
standard wastewater evaporation equipment. The non-hazardous liquid is sent to the atmosphere
reducing everything down to solder paste for recycling and small amounts of dry detergent
residue for disposal as solid industrial waste. There is absolutely no liquid hazardous waste for
disposal and no liability associated with drain disposal!

Other Cleaning Applications - While the Smart Sonic Stencil Cleaning Process is guaranteed to
clean any type of solder paste from any fine-pitch stencil, the process is not limited to cleaning
solder paste.  By slightly raising the wash temperature from ambient to 110 degrees F. (43
degrees C.), wet SMD adhesives can be cleaned from stencils and misprinted PCBs and post
solder flux residue can be cleaned from reflow and wave solder pallets, oven radiators, conveyor
fingers and other tooling.

New Cleaning Systems - Smart Sonic Corporation has introduced several new cleaning systems:

  •  The Model 1500 Stencil &  Pallet Cleaner for small and startup PCB assemblers;
  •  The Model 2003 Stencil &  Pallet Cleaner for cleaning solder paste at ambient temperature
     and SMD adhesives or post solder flux residue at elevated temperatures in the same machine
     and at the same time; and
  •  The Model 5000 fully automated stencil cleaner which uses less chemistry than the Model
     4200 and offers an optional drying cycle.

Smart Sonic has also introduced the Model EZ-0 Wastewater Evaporator, The EZ^O prevents
waste residue scorching for easy clean out and is ergonomically designed for ease of maintenance.

Award Winning Process - Since the introduction of the Smart Sonic Stencil Cleaning Process in
1990, the process has been evaluated and tested by recognized experts in the field of surface
mount technology, field tested by over 500 installations worldwide and, most recently, by
California's South Coast Air Quality Management District.

In 1995, Smart Sonic was presented the "SMT Vision Award" at the Surface Mount International
Show, San Jose, CA for introducing the industry's first truly environmental and user safe stencil
cleaning process.

In 1998, Smart Sonic was again awarded the "SMT Vision Award" for the introduction of the
Model  5000 Stencil and Pallet Cleaner. The Model 5000 uses less than half the chemistry of it's
predecessor (the Model 4200) and can wash, rinse and safely dry a stenpil in less than 6 minutes
which is three times faster than the nearest competitor.

                                          27

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The Smart Sonic Stencil Cleaning Process has also received the Canadian High Technology
Award for Best New Product and was a finalist for the NEPCON West Milton S. Kiver Award
(Excellence Award) for Excellence in Electronics Packing & Production.

Smart Sonic Contact -The latest information about Smart Sonic products can be obtained from
Smart Sonic at:
         Tel: 1(805) 499-7440
         Fax: 1(805) 375-5781
e-mail: bill@smartsonic.com
http ://www.smartsonic.com
                Availability of Verification Statement and Report
           Copies of the public Verification Statement (EPA/600/R-99/004VS) and
          Verification Report (EPA/600/R-99/004) are available from the following:

               (Note: Appendices are not included in the Verification Report.
                   Appendices are available from DTSC upon request.)
               1. USEPA/NSCEP
                  P.O. Box 42419
                  Cincinnati, Ohio 45242-2419

                  Web site: http://www.epa.gov/etv/library.htm (electronic copy)
                           http://www.epa.gov/ncepihom/ (order hard copy)
               2. Department of Toxic Substances Control
                  Office of Pollution Prevention and
                       Technology Development
                  P.O. Box 806
                  Sacramento, California 95812-0806

                  Web site: http://www.dtsc.ca.gov/sppt/opptd/etv/txppetvp.htm
                       or   http://www.epa.gov/etv (click on partners)
                                         28
                                                  &U.S.
                                                      GOVERNMENT PRINTING OFFICE: 1999 -750-101/00033

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