40 CFR § 68.30 - Defining offsite impacts—population.
---
identifier: "/us/cfr/t40/s68.30"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 68.30 - Defining offsite impacts—population."
title_number: 40
title_name: "Protection of Environment"
section_number: "68.30"
section_name: "Defining offsite impacts—population."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "68"
part_name: "CHEMICAL ACCIDENT PREVENTION PROVISIONS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7412(r), 7601(a)(1), 7661-7661f."
regulatory_source: "59 FR 4493, Jan. 31, 1994, unless otherwise noted."
cfr_part: "68"
---
# 68.30 Defining offsite impacts—population.
(a) The owner or operator shall estimate in the RMP the population within a circle with its center at the point of the release and a radius determined by the distance to the endpoint defined in § 68.22(a).
(b) *Population to be defined.* Population shall include residential population. The presence of institutions (schools, hospitals, prisons), parks and recreational areas, and major commercial, office, and industrial buildings shall be noted in the RMP.
(c) *Data sources acceptable.* The owner or operator may use the most recent Census data, or other updated information, to estimate the population potentially affected.
(d) *Level of accuracy.* Population shall be estimated to two significant digits.