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BlueWave® MX-Series Multichannel Controller User Guide
Standard Dymax UV light-curing systems have been designed primarily to emit UVA and Visible energy (Figure 1).
Depending on the model of LED head used, the energy emitted from a
BlueWave
MX-Series curing system can
either be in the upper end of the UVA portion of the spectrum (PrimeCure® and RediCure®) or in the lower portion
of the visible spectrum (VisiCure®). UVA energy is generally considered the safest of the three UV ranges: UVA,
UVB, and UVC. Although OSHA does not currently regulate UV-light exposure in the workplace, the American
Conference of Governmental Industrial Hygienists (ACGIH) does recommend Threshold Limit Values (TLVs) for
ultraviolet light.
The strictest interpretation of the TLV (over the UVA range) for workers’ eyes and skin allows continuous exposure
up to 1 mW/cm
2
(intensity). Unless you are placing bare hands into the curing area, it is unusual to exceed these
limits. To put 1 mW/cm
2
limit into perspective, a cloudless summer day will typically exceed 3 mW/cm
2
of UVA
light, and also include the more dangerous UVB light (primarily responsible for sun tans, sun burns, and skin
cancer).
Checking the Workstation
The human eye cannot detect "pure" UV light, only visible light. A radiometer should be used to measure stray UV
light to confirm the safety of a UV light-curing process. A workstation that exposes an operator to more than 1
mW/cm
2
of UVA continuously should be redesigned.
Protecting Operators
Light-curing technology can be a regulatory compliant, "worker-friendly" manufacturing process when the proper
safety equipment and operator training is utilized. There are two ways to protect operators from UV exposure:
shield the operator and/or shield the source.
Shield the Operator
UV-Blocking Eye Protection
—
UV-blocking eye protection is recommended when operating UV light-curing
systems. Both clear and tinted UV-blocking eye protection is available from Dymax.
UV-Blocking Skin Protection
—
Opaque, UV-blocking clothing, gloves, and full-face shields are recommended
when skin may potentially be exposed to UV light.
Shield the Source of UV
Any substrate that blocks UV light can be used as a shield to protect workers. The following materials can be used
to create simple shielding structures:
Rigid Plastic Film
—
Transparent or translucent/UV-blocking plastics (typically polycarbonate or acrylic) are
commonly used to create shielding where some level of transparency is also desired.
Flexible Film
—
Translucent UV-blocking, flexible urethane films can be used to quickly create workstation
shielding. This UV-blocking, flexible urethane film is available from Dymax, call for assistance.
High-Temperature Surfaces
Surfaces exposed to high-intensity curing energy may rise in temperature. The intensity, distance, exposure time,
cooling fans, and composition of the surface can all affect the rise in surface temperature. In some cases, exposed
surfaces can reach temperatures capable of producing a burn or causing damage to a substrate. In these cases,
operators should try to minimize exposure to maintain a cooler surface temperature or they should have the
