Are nitrile gloves adequate protection from exposure to UV light in the workplace?

With normal shielding of UV curing equipment, workers are exposed only to reflections of UV light, and normal work clothing provides adequate attenuation of UV radiation in the workplace. Most polymers and pigments are strong absorbers of UV radiation, so even a thin layer of pigmented nitrile rubber is very effective protection from UV light, which does not have much penetrating power. Even unpigmented gloves should provide adequate protection from reflected UV light.
Of course, worker training to use the correct protective equipment and to recognize the symptoms of over-exposure is essential. The symptoms of over-exposure to UV light are the same as sunburn, so workers will notice very quickly if their protective gloves or clothing are inadequate for conditions, and you can enhance the protection if necessary.

UV, EB, CO2

RadTech is increasingly being asked about the role UV and EB technology may play in efforts to develop cleaner technologies that reduce greenhouse gas emissions.
In 2005, the RadTech Technical Committee weighed-in on the issue with the following observations:

- UV/EB technology can be a “one-stop shop” for businesses to keep up with state, national and international requirements. Adoption of UV/EB processes can assist compliance with U.S. regulations as well as with those that businesses face abroad.
- The EPA and local air districts agree that UV/EB is good news for the environment. The overwhelming majority of UV/EB coatings, inks and adhesives contain little or no volatile solvent. Solvents, when incinerated, generate additional greenhouse gases from combustion.
- Emissions of VOCs, which are tropospheric (ground-level) ozone precursors, can be nearly eliminated with the use of UV/EB technology. Ground-level ozone is estimated by the EPA to be the third largest contributor to climate change.
- As one example of the savings that has already been achieved through the use of the technology, a major industry study of a UV process line found an over 65% reduction in greenhouse gas emissions. The study compared UV curing to a water-borne coating line equipped with incineration. There was also a documented 80% reduction in the total amount of energy used by the facility. As a result of these energy efficiency advances, the study noted that the energy savings offered by UV/EB technology translated into 62 billion BTU/year for the company, and achieved as much as a 55% reduction in capital and installation costs over thermal curing. While the benefits of UV/EB technology may vary depending on the particular facility and the intended use of the technology, this study and the experience of this industry demonstrate that EB and UV curing may be used to achieve meaningful voluntary reductions of greenhouse gas emissions.
- The use of UV/EB-curing processes can inherently reduce greenhouse gas emissions by reducing reliance on the burning of fossil fuels. UV/EB technology is highly energy efficient, utilizing equipment that is relatively cooler and smaller than that used for other drying methods. In addition, it can cure materials at or near room temperature in a matter of seconds or less. For these reasons, the total energy used in UV/EB-curing processes can be significantly lower than the energy needed for thermal drying, resulting in energy savings and reduced reliance on the burning of fossil fuels that contribute to greenhouse gas emissions.

We hope you may share your further information and data? For example, in one illustration offered by a RadTech member: Since much less material is used to coat a given substrate for many UV/EB applications, far less chemistry is trucked to manufacturing facilities--offering substantial savings on the energy used and emissions generated for transportation.

What are your thoughts?

Cross posted:
RadTech LinkedIn— http://www.linkedin.com/groups?gid=1799180&trk=hb_side_g
RadTech Blog— http://www.uveb.blogspot.com/

NYSERDA announces the upcoming release of Program Opportunity Notice (PON) 1641

Congrats to the UV & EB industries for NYSERDA support of our technology. Details will be released at uv.eb EAST (www.uvebeast.com). NYSERDA will have reps at the event to provide details...
NYSERDA announces the upcoming release of Program Opportunity Notice (PON) 1641: Ultraviolet Light (UV) and Electron Beam (EB) Process Innovation and Market Transformation. The solicitation will provide incentives for New York State industrial sites to adopt innovative UV and/or EB processes within their manufacturing process, or for New York State technology developers to produce an innovative UV/EB product, process or service that will provide an energy benefit to end users. The release of this solicitation will coincide with NYSERDA’s jointly sponsored conference with RadTech, entitled UV/EB East, which will be held at the Niagara Falls Conference Center, Oct. 20-21, 2009.
“PON 1641 demonstrates NYSERDA’s commitment to support the deployment of environmentally friendly technologies and will provide up to $2 million for research and demonstration projects within New York State,” said Francis J. Murray, Jr., NYSERDA President and CEO. “The increased adoption of ultraviolet light and electron beam curing technologies complements the vision of Governor Paterson’s energy efficiency agenda and will enable New York State manufacturers to remain competitive and create clean energy jobs for the future.”
NYSERDA has provided incentives for a number of notable UV and EB projects through funding opportunities that sought proposals covering a wide array of technologies. PON 1641 is NYSERDA’s first targeted UV/EB solicitation.

We are formulating inks for a label on the outside of a plastic cup.

The label reaches all the way to the top lip of the cup, so it is likely that the person drinking from the cup will physically have their mouth in contact with the label and will ingest some of the liquid contents that have come into contact with the outside of the printed label. Is this a direct food contact application, and must the printing on the label be cleared under the FDA regulations for direct food contact?

There are two possible answers, depending on the intended use for the cup.

1. If the labeled cup is used as food or beverage packaging, it is reasonable to expect that substances that have the potential to migrate from the label will be ingested by mouth contact along with the food, and any inks, coatings or adhesives used to manufacture the label must be FDA compliant. They must meet any applicable requirements for composition and extraction testing, or it must be shown that any migration of uncleared component substances is below the level of regulatory concern.
2. If the labeled cup is intended for use solely as a household container, it may fall under the “FDA housewares” exemption, which holds that materials used to manufacture empty containers, dinnerware, eating utensils or appliances sold to consumers for home use do not require food additives clearance.

In both cases, it is advisable to obtain legal confirmation that the inks, coatings or adhesives used to manufacture the label and the finished article comply with all regulations that apply for the intended use.

Is there an established test method for the analysis of VOC/solids of UV coatings and inks?

Until recently the ASTM D-5403 test method was the accepted standard test method for determining the VOC content of UV/EB curing materials. Test Method D-5403A is applicable to radiation curable materials that are essentially 100% reactive but may contain traces (no more than 3%) of volatile materials as impurities or introduced by the inclusion of various additives. Test Method D-5403B is applicable to all radiation curable materials but must be used for materials that contain volatile solvents intentionally introduced to control application viscosity and which are intended to be removed from the material prior to cure. You can purchase a copy of this standard at http://www.astm.org/Standards/D5403.htm.

Recently, a RadTech ad hoc Committee developed a new test method that is particularly suited to thin films of applied wet coating (please contact RadTech for more information). This method is currently under review by ASTM.

We are applying coatings to the inside of metal food storage tanks, but a preferred primer is not FDA compliant. Can we apply a UV curable coating...

that complies with FCN 772 over the primer as a functional barrier to comply with FDA regulations?

A functional barrier must assure that any potential migration of FDA non-compliant substances not in contact with food or beverages is below the “Threshold of Regulation”, i.e. less than 50 ppb in the food. If a coating that complies with FCN 772 is to function as a functional barrier, it must meet three criteria:
1. The UV cured coating must meet all of the composition and extractable monomers and total extractable solids requirements of FCN 772.
2. The UV cured coating must demonstrably prevent migration of any of the uncleared primer components into the food at levels above 50 ppb.

Both of these requirements must be demonstrated by conducting extraction tests with appropriate food simulants as specified in Appendix II, SELECTED MIGRATION TESTING PROTOCOLS, at the FDA Preparation of Premarket Submissions for Food Contact Substances: Chemistry Recommendations web site http://www.cfsan.fda.gov/~dms/opa3pmnc.html#aii.

3. The UV coating must reasonably be expected to continue to serve as an effective functional barrier over the lifetime of the manufactured article (food storage tank).

The design of the tank for the intended application, the compositions of the primer and coatings, and the design and results of the extraction testing protocols and results should be subjected to qualified legal review to assure compliance with FDA regulations.

A RadTech member received a question regarding the inclusion of benzophenone in a coating used to protect the surface of a label.

While indirect food contact was not specifically mentioned, I'm sure that's the issue. If I visit the website below, I find benzophenone on the GRAS list and accepted for direct food contact CFR21 172.515 http://vm.cfsan.fda.gov/~dms/eafus.html

This is more a question of whether the benzophenone might affect the flavor and/or odor of the packaged product than food safety. Not only FDA, but also the European authorities have determined that benzophenone is safe in food. Assuming that the customer's product is not affected by the odor of benzophenone, the small amount of benzophenone that could migrate into packaged food from the label should not be a health issue. The RadTech member page has a link to analyses of typical migration of benzophenone into food. A calculation also can be done to estimate the magnitude of the migration and confirm the health safety.
Flavor and odor are another question. Benzophenone should not be used in packaging for chocolate, for example. Chocolate picks up off flavors very easily and would be affected by even the smallest traces of benzophenone. Benzophenone and any other highly odorous materials must be avoided in such cases.
In summary, it is best to ask the customer what they are packaging and confirm ahead of time that the benzophenone is not a problem for their particular application. You can show them the FDA and EU positive clearances and typical migration analyses if they want more information. If they still are not comfortable with it, take BPO out of the formulation; it will be a continuing concern and may come back to haunt you if the customer later has problems that they decide to blame on BPO.