Characterizing
Thermal Spray Emissions
Thermal spray is growing in popularity because it provides surface properties
for metal and non-metal substrates. Thermal spray is also generally considered
to be an environmentally-preferable alternative to chrome plating. However,
given the emotionally-charged regulatory atmosphere, actual studies to characterize
the overspray have not been conducted. The California Air Resources Board (CARB)
recently passed regulations requiring HEPA filters for many thermal applications.
BFK Solutions has evaluated available literature and has also surveyed key industry players including government, military (the HCAT program), pertinent individuals in academia, manufacturers that apply thermal spray coatings, producers of powders and wire, and manufacturers of spray booths and filters designed to capture the overspray. Opinions and calculations abound; data are sparse. BFK Solutions is working with industry and academia to characterize the overspray (the output of the thermal spray gun that is not applied to the product) in terms of:
Particle size distribution
Content of the particles (with the emphasis on hexavalent chrome and nickel)
Such studies are needed to determine if HEPA filters are necessary, appropriate, or sufficient.
Site Assessments, Waste Minimization Plans, Alternate Operating Scenarios
Waste Minimization Plan; Semiconductor
• regulatory difficulties; waste minimization plan unacceptable
• team approach to plan revision
• revised plan improved productivity and was acceptable to regulatory agency
A company involved in semiconductor and wafer fabrication had had a plan for waste reduction and solvent substitution rejected by a regulatory agency. The initial plan was fairly generic; and was therefore unconvincing to the regulators.
In order to provide an improved plan, with the permission of the company,
the appropriate regulators were contacted in order to ascertain
specifics to improve
the plan. In addition, a site assessment was conducted, and,
with management support, brainstorming sessions were held with technicians,
engineers,
and management. Based on these sessions, specific action plans
were
developed which
would:
• meet the needs for an improved plan
• improve productivity
• be consistent with upcoming product lines
One manager commented: “Our people were clams; you’ve gotten them to open up and talk with each other.”
The revised waste reduction plan was submitted and accepted;
and the company had viable approaches to improve productivity.
Bearings, Seismic Protection
• automate process to minimize worker exposure; decrease process variability
• resolve “Catch 22” regulatory conflict involving multiple local, state and Federal agencies
One typically thinks of bearings as being fairly small, or even miniature components. Bearings for seismic protection (buildings, bridges) may weigh in excess of one ton. As with smaller bearings, they have exacting regulatory and customer requirements for long-term performance and reliability. The facility had validated, contractually-established a process using a specific aggressive solvent for cleaning prior to bonding. However, local authorities were attempting to impose use of HCFC 141b, a VOC-exempt solvent. To further complicate the situation, HCFC 141b usage was banned at the Federal level.
While the solvent selected by the bearing manufacturer
could not be changed for contractual and performance
reasons, the
cleaning process
itself
required optimization to assure consistent performance
and to minimize
hazards to workers.
Initially, assemblers were attempting to manually
guide the very heavy bearings into a large, open-top
degreaser.
The
size and
mass of the
parts inherently
precludes maintenance of a vapor blanket; so
employees had short-term exposure to high solvent levels.
Of more immediate
importance,
the size of the part
to be cleaned posed a potential for blunt trauma
to the workers.
To resolve the worker safety and process control
problems, the large bearings were harnessed,
fixtured, and the
process automated.
In
addition, BFK Solutions
facilitated the interchange of local regulatory
authorities and Federal authorities. Finally,
a detailed cost
and performance analysis was
performed to establish
that the process was the Best Available Control
Technology (BACT);
and BFK Solutions provided effective support
at the local hearing. The “Catch
22” issue was successfully resolved; the company
was allowed to use the efficacious solvent that was
needed.
Trade Association Facilitation, OEHHA
OEHHA, the Office of Environmental Health Hazard
Assessment, is a California State Agency
that evaluates available
toxicity data for
chemicals and
sets risk factors. These factors are often
used by other agencies. A trade association,
consortium of solvent manufacturers faced
fast-track regulation of relatively newly-developed solvent
by OEHHA. The association
took
the position that,
while the solvent ought to be tracked, there
was no justification to fast-track the
evaluation. At the request of the trade association,
BFK Solutions evaluated animal studies, current
usage data,
alternatives, and projected economic
outlook in a range of applications. We presented
both written and oral data to the
OEHHA advisory board, comprised of a group
of
independent clinicians.
The unanimous decision was that fast-tracking
of the solvent was not justified. While there
is no way to promise a favorable outcome,
we will
evaluate your situation. If we work with
you, we will provide
appropriate, rational, justifiable
support.
Production,
Temperature Sensitive Tape, Permitting
A specialized, temperature sensitive tape
is used in a variety of clinical and
commercial devices.
The technique
is complex
and not
completely
understood. However, an array of solvents
are
used. The client wished to relocate
the process to an area of poor area quality
with stringent regulatory requirements.
BFK
Solutions observed the process and suggested
approaches to solvent minimization, to
maintenance of process
quality, and to improvement
of process consistency.
With the client’s permission, we
photographed the process. We then found
the appropriate personnel
at the regulatory agency
in question and
presented
the information. We were successful in
convincing the agency that the process
could be conducted at
the proposed new location. The
client was able to
avoid having to move the process out
of the United States.
