MANAGING BEST PRACTICES: Contact lenses and chemicals
Until the mid-1990s, most employers banned the use of contacts among workers in industrial environments. The bans were based mostly on now disproved claims: Exposure to arc flash could fuse contacts to the cornea, or chemicals could readily be concentrated within or underneath the contacts and cause injury or blindness.
Around the same time, studies began showing that contacts offered protection in some cases from chemical exposure. One study showed that hard contact lenses decreased corneal damage when the eye was splashed with acids such as acetic, n-butylamine, and acetone. Another study showed that soft contacts did absorb trichloroethylene and xylene vapors, but the solvents were released primarily back into the air and not the eye.
Today, the greatest confusion surrounds interpretation of hazards and industrial hygiene recommendations to prohibit contact use in work environments. Most occupational safety and health references advise against wearing contact lenses when working with chemicals. Nearly every chemical listed in NIOSHâ€™s current Pocket Guide to Chemical Hazards advises in the first-aid section that: â€œContact lenses should not be worn when working with this chemical.â€ Probably because of the NIOSH references, material safety data sheets (MSDS) generally carry the recommendation not to wear contacts when handling the product.
Professional judgmentHereâ€™s my approach to use of contact lenses: My medical insurance covers eye exams and pays for a periodic supply of contact lenses, but the insurance will not pay for prescription eyeglasses. I donâ€™t know if this is standard practice today with medical insurance programs, but it seems plausible.
As an IH consultant Iâ€™m in and out of a variety of workplaces, most requiring eye-protection while being in the production areas. I used to wear my contacts all the time when performing IH work but I donâ€™t anymore. I now always wear ANSI Z-87 approved safety-glasses with side-shields when doing jobs. Thereâ€™s one exception, though. If I expect to wear a full-face respirator, I will wear my contacts.
My preference of eyeglasses over contacts was not based on hazards I generally faced, but on the standard guidance language used in International Chemical Safety Cards. Use of eyeglasses also avoids my having to consider an employerâ€™s contact lenses use policy, although the topic rarely comes up.
If clients have questions on worker use of contact lenses, I refer them to the ACOEMâ€™s 2003 guidance document on the topic (see sidebar). As for IH recommendations, as a general rule of thumb I believe that employees should not use contacts whenever exposure to chemicals with irritation-critical effects possibly exceeding 50 percent of the threshold limit value. Although the TLV for â€œparticles not otherwise specifiedâ€ may not be based upon irritant effects, I include them in this category.
Each situation, though, should be judged on its own merits. In addition to chemicals, exposure to UV and IR radiation, intense heat, and dry air must be considered as potential hazards affecting the use of contact lenses.
Because the use of contacts is expected to grow among workers (aging workforce, growing preference among people to use contacts, etc.) you should remain alert to new findings and recommendations on this topic. If you have not already done so, itâ€™s important to establish a policy on contact lenses for your employer. And note that old information and myths remain on references to use of contact lenses. To fully understand new studies, read the entire study and not just the abstract.
SIDEBAR: What OSHA saysOSHA does not specifically ban use of contact lenses in any of its standards. Regulatory language is always advisable. For example, the methylene chloride standard at 29 CFR 1910.1052, Appendix A, states, â€œContact lenses should not be worn when working with this chemical.â€ The standard on occupational exposure to hazardous chemicals in laboratories at 29 CFR 1910.1450, Appendix A, states, â€œAvoid use of contact lenses in the laboratory, unless necessary.â€ And standards (e.g. respiratory protection) that reference consensus standards (e.g. ANSI) also use advisory language.
OSHA compliance officers might issue a citation based upon advisory language if they feel the hazard warrants it, but employers could be successful if they challenge the citation in informal or formal hearing when they disagree with the finding.
SIDEBAR: ACOEM guidelinesThe American College of Occupational and Environmental Medicineâ€™s (ACOEM) May 2003 guideline on The Use of Contact Lenses in an Industrial Environment (http://www.acoem.org/guidelines/pdf/ContactLenses-Guideline052003.pdf) concludes that contact lenses are not protective devices, but â€œworkers (should) be permitted to wear contact lenses when handling hazardous chemicals and in other eye hazardous environmentsâ€ provided ACOEM guidelines are followed. The guidelines are:
- Establish a written policy;
- Conduct an eye hazard evaluation;
- Provide training;
- Provide personal protective equipment;
- Notification to visitors; and,
- Notification to supervisors, first-aid responders and EMS responders.
ACOEM also lists three conditions when contact lenses should not be worn in the workplace:
1) Banned by regulation;
2) Contraindicated by medical or industrial hygiene recommendations; and
3) When working with acrylonitrile, 1, 2,-dibromo-3-chloropropane, ethylene oxide, methylene chloride, and 4, 41-methylene dianiline (until OSHA changes rules).