MAP20071018068 TLVs threshold limit values for physical agents : adopted by ACGIH for 1977 Sumario: Limits at which most workers may be exposed without ill effects have been published by ACGIH for heat stress, ionizing radiation, noise, and vibration. These threshold limits are based on the best available information from industrial experience, from experimental human, and animal studies, and when possible from a combination of the three En: National safety news. - Chicago. - Vol, 116, nº 4, October 1977 ; p. 65-71 1. American Conference of Governmental Industrial Hygienists . 2. Higiene industrial . 3. Valores TLV . 4. Contaminantes físicos . 5. Normas . 6. Ruido . 7. Vibraciones . 8. Radiaciones ionizantes . 9. Estrés térmico . 10. Láser . 11. Radiaciones ultravioletas . 12. Microondas . I. Title. II. Título: National safety news.