“Chronic” means an exposure that lasts between one year and a lifetime in duration.

Source. #6328, INTERIM, eff 8-24-96, EXPIRED: 12-22-96 New. #6468-A, eff 3-5-97; renumbered by #8256 (from Env-A 101.65), (see Revision Note #1 at chapter heading); renumbered by #8304 (see Revision Note #2 at chapter heading); renumbered by #9839 (from Env-A 101.40), (see Revision Note #3 at chapter heading); ss by #13105, eff 9-25-20 (formerly Env-A 101.41) (see Revision Note #4 at chapter heading for Env-A 100)