To design an effective prevention program in health care workers who are allergic to latex it is necessary to know the current epidemiological situation. The objectives were to determine the main factors associated with latex allergy and to quantify levels of airborne latex particles in different areas of our hospital. A cross-sectional study was conducted using a questionnaire completed by health care workers. Those who answered the first questionnaire were given a second one to fill out and an allergological study (skin-prick test and latex-specific IgE antibodies) was performed. Latex aeroallergen particles were collected with a Quan-tec-air in different areas of the hospital. The first questionnaire was sent to 2551 health care workers. Eight hundred forty-one (33.14%) subjects returned the completed questionnaire and were given the second questionnaire. One hundred fifty-four completed second questionnaire. We identified 28 patients who were allergic to latex, and 126 patients who were not allergic to latex. In the allergic population there were more nurses aides. More allergic patients were found in the Surgery Department, Intensive Care Unit (ICU), and Vascular Radiology Unit (VRU). Allergic patients were more likely to use a higher number of latex gloves and during more hours than nonallergic workers. In the Surgery Department, ICU, VRU, and Laboratory Department more pairs of latex gloves were used and during more hours. The medium level of latex aeroallergens in 24 determinations in 14 areas of the hospital was 8.12 ng/m3 (SD, 13.32 ng/m3; range, 0.3-57.7 ng/m3). The higher levels were found in Laboratory (n = 2; mean (M) 23; SD, 25.95 ng/m3) and Surgery Departments (n = 11; M, 7.43; SD, 16.98 ng/m3; Kruskal Wallis test, p = 0.09). Latex allergy is an important health problem for health care workers, especially for those working in surgical areas or in those places where more latex gloves are used; in these areas higher levels of airborne latex particles are found. We should take into account these data to design an effective secondary prevention program.