Biomedical Engineering Reference
In-Depth Information
waterways. If very little cutting fluids are used in the machining processes
employed by a manufacturer, it is likely that the overburden produced in the
various processes is solid in nature and will be dealt with as either a solid or
hazardous waste. Of course, the regulations aimed at managing and controlling
hazardous wastes versus solid wastes is more involved and appreciably more
costly.
One specific type of machining process which is finding increasing
prominence in biomedical device manufacturing is laser cutting. However, in
addition to cutting processes, lasers are also used frequently in device
manufacturing as a means for welding, sealing, and coating products. Lasers
can even be found as a functional part of the device itself. Thus, some
discussion on the environmental health and safety aspects of using lasers has
considerable merit. Depending on both the nation and type of laser, exposure
guidelines and mandated standards can vary significantly. The thresholds
limits developed for safe operation are normally expressed as a maximum
permissible exposure and are published by such groups as ANSI, ACGIH,
ICNIRP, and IEC [Hitchcock et al., 2003]. The major target organs for lasers
are the eyes and skin. Fortunately, many of the lasers used in biomedical
device manufacturing and in the specific products do not cause a significant
environmental pollution concern. However, some toxic chemicals such as
fluorine and organic solvents are used within the laser itself. Means for
disposing of a laser after its useful life varies from nation-to-nation, with many
just allowing the discarding of the devise in the regular solid waste refuse.
EH&S
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W
ELDING
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OLDERING
Welding and soldering operations are many times used in the industry to
attach the various device parts together. These activities can sometimes pose
and exposure risk to employees not wearing the proper clothing, eyewear, and
other personal protective equipment. The main occupational hazards
associated with joining operations such as these include skin burns, ―welder's
flash‖, electrical shock, and significant overexposures to both heat stress and
toxic gas and vapor concentrations.
One of the biggest concerns regarding the soldering process has always
been the use of lead metal in the solder. Lead is an extremely acute and
chronic toxin linked to several potential health detriments for those
overexposed. Fortunately, for developed countries, the formulation of the
solder material no longer has significant quantities of lead. However, many
