The Value of Interchange for Contamination Control
Barbara Kanegsberg and Ed Kanegsberg, February 2004
We recently participated in a valuable, thought-provoking workshop;1 this annual
conference deals with the confluence of military requirements for critical
applications of environmental, regulatory and/or legislative changes, and of
practical, achieved approaches to production and maintenance of product quality.
The emphasis is on surfaces, both cleaning and coating, and on contamination
control. The conference is particularly valuable for the forthright, sometimes
pointed comments of the speakers and the similarly frank, incisive comments
and questions from the audience. This month we will discuss a few topics presented
at the workshop.
Biobased Materials
Biobased products, derived from renewable plant or animal materials,
the topic of several presentationseg. 2,3 raise both opportunities
and potential contamination
control issues. Given recent legislation4 and near-term regulations,5 the
Federal government will, in most cases, have to purchase biobased
products. As a consequence,
biobased products are likely to be strongly encouraged, even in the private
sector. Research and development dollars are being focused on biobased lubricants,
oils, and other metalworking fluids as well as on biobased cleaning agents.
There are positive aspects to this trend. Products based on renewable resources
are important economically and politically. In addition, such products offer
the possibility of new, favorable characteristics. For example, nutritionists
and chemists at pharmaceutical companies continually find hitherto unknown
compounds in plants.
At the same time, introduction of biobased products raises potential
contamination control issues. Where biobased products are used for
lubricants and metalworking
fluids, processes for their effective removal must be devised. In addition
some biobased products such as d-limonene are very effective in removing
adherent soils. However, d-limonene leaves a residue, albeit one which
can be readily
removed by sequential rinsing with a more volatile solvent such as isopropyl
alcohol.6 Soy-derived materials (methyl soyate) have similar properties.
As such products are introduced for more critical applications, establishing
appropriate
cleanliness verification procedures and surface quality procedures will
be imperative.
Contamination Control, Cleanliness Standards
One case study7 involving manufacture of space shuttle windows demonstrates
that contamination may still be present even if it has not been observed.
An improvement in the optical inspection technique of the windows revealed
a previously
undetected haze. Subsequent investigation led to the identification
of the source of this contamination and to development of a method for removal
of
the haze.
Knowing the Variables
Results of a survey of implementation of cleaning processes were presented(8).
The study, sponsored by the Toxics Use Reduction Laboratory (TURI)
of University of Massachusetts, Lowell, involved groups who had worked with
TURI
to develop
alternative surface cleaning processes. Over 70% of the respondents
did not know the suppliers or trade names of the cleaning agents currently
in use
at their company. Understanding the cleaning process is a key to successful
contamination
control. Changes in soils, materials of construction, or product
design, potentially impacts contamination level. Cleaning is an important part
of contamination
control; and, without a clear understanding of the nature of the
cleaning
agent,
process monitoring is incomplete.
Asking the Questions; the Issues
No resource or event is likely to answer all of oneís questions
about contamination control. A key value of this workshop is that contamination
control,
cleanliness and performance issues are addressed in a forum where frankness,
honest discussion of issues, and public interchange between presenters
and other attendees is encouraged. As important, those involved in technology
advancement
and in day to day product performance, interact not only with each other
but with those who develop environmental regulations. Because both performance
requirements and constraints (e.g. environmental, legislative, costs) are
likely
to increase, such interchanges continue to be not just relevant but crucial.
1 14th Annual International Workshop on Alternatives to Toxic Materials
in Industrial Processes (Formerly International Workshop on Solvent
Substitution), Scottsdale Arizona, Exchange Monitor Publications & Forums, (December
8-11, 2003).2 M. Duncan, ibid3 K. Kristoff, ibid.4 Section 9002 of the
Farm Security
and Rural Investment Act of 2002 (FSRIA), 7 U.S. C. 8102. See http://www.biobased.oce.usda.gov/public/index.cfm5
Federal Register, Proposed Rule, Biobased products designation guidelines
for Federal procurement, 70730-70746, (December 19, 2003).6 B. Kanegsberg,
14th
Annual International Workshop, op cit.7 S. Apel, ibid.8 C. LeBlanc, ibid
Barbara Kanegsberg and Ed Kanegsberg are independent consultants in critical cleaning, precision cleaning, surface preparation, and contamination control. They are the editors of “Handbook for Critical Cleaning,” CRC Press. Contact them at BFK Solutions LLC., 310-459-3614; info@bfksolutions.com; www.bfksolutions.com.
