This docum ent is in the public domain and may be freely copied or reprinted.M ention of any com pany or p roduct does n o t co n stitu te en d o rsem en t by the N ational In stitu te for O ccupational Safety an d H ealth (NIOSH). In addition, citations to Web sites external to NIOSH do n o t co n stitu te NIOSH en d o rse m e n t of th e sponsoring organizations or th eir program s or products. F u rth er m ore, NIOSH is n o t responsible for th e co n ten t of these Web sites.To receive docum ents or o th er in fo rm atio n ab o u t occupational safety and h e alth topics, contact NIOSH at NIOSH-Publications D issem ination 4676 Colum bia Parkw ay C incinnati, OH  # Foreword
The purpose of th e O ccupational Safety an d H ealth Act of 1970 (Public Law 91-596) is to assure safe a n d h ealth fu l w orking conditions for every w orking person an d to preserve our h u m a n resources. In this Act, th e N ational In stitu te for O ccupational Safety an d H ealth (NIOSH) is charged w ith recom m ending occupational safety an d h e alth stan d ard s an d describing exposures th a t are safe for various periods of em ploym ent, including (but n o t lim ited to) th e exposures at w hich no w orker w ill suffer dim in ish ed h ealth , fu n c tional capacity, or life expectancy as a resu lt of his or h er w ork experience.
C urrent Intelligence B ulletins (CIBs) are issued by NIOSH to d issem inate new scientific inform ation about occupational hazards. A CIB m ay draw a t ten tio n to a form erly unrecognized hazard, report n ew d ata on a k n o w n h a z ard, or dissem inate inform atio n ab o u t h azard control. CIBs are d istrib u ted to representatives of academ ia, industry, organized labor, public h e a lth a g en cies, an d public in terest groups as w ell as to Federal agencies responsible for ensuring th e safety an d h e alth of w orkers. This CIB reviews w h a t is k n o w n about contact lens w ear w hile w orking w ith chem icals an d provides guidelines for th eir use in a chem ical en v iro n m en t to help em ployers safely im plem en t a contact lens use policy.   Hejkal et al. 1992;N ilsson an d A ndersson 1982]. In th ese experim ental studies, v ari ous lens m aterials w ere exposed to ch em i cals for ex ten d ed periods using eith er vials or anim als. The results suggest th a t contact lens u ptake an d release of chem icals to eye tissue is n o t likely to be a significant issue 1 for w orkers w earing contact lenses. H ow ever, one sim ilar laboratory in vitro study indicates th a t isopropyl an d ethyl alcohol m ay pose risks to exposed w orkers w earing contact lenses .
In all of these studies, researchers exam ined the resistance of contact lenses to chemical exposures under test conditions. They did not examine actual chemical exposures in w ork ers and did not exam ine the use of appropri ate eye protection sim ultaneously w ith con tact lens use. The eye injury hazard evaluation should be conducted by a com petent, qualified person such as a certified industrial hygienist, a cer tified safety professional, or a toxicologist.
In fo rm atio n from th e h azard evaluation should be provided to th e exam ining oc cupational h e a lth n u rse or occupational m edicine physician.
The chem ical exposure assessm ent for all w orkers should include, at a m inim um , an evaluation of th e properties of th e chemicals in use-including concentration, perm is sible exposure limits, k now n eye irritan t/ injury properties, form of chem ical (pow der, liquid, or vapor), and possible routes of exposure. The assessm ent for contact lens w earers should include a review of the available inform ation about lens absorption and adsorption for th e class of chemicals in use an d an account of th e injury experience for th e employer or industry, if know n. These recom m endations are for w ork w ith chem ical hazards. They do n o t address h a z ards fro m h e a t, ra d ia tio n , or h ig h -d u s t or h ig h -p a rticu la te environm ents.