28 CFR 570.32 - Types of furloughs.
A furlough is an authorized absence from an institution by an inmate who is not under escort of a staff member, U.S. Marshal, or state or federal agents. The two types of furloughs are:
(a) Transfer furlough - A furlough for the purpose of transferring an inmate from one Bureau facility to another, a non-federal facility, or community confinement (including home confinement) as noted below at § 570.33(a).
(b) Non-transfer furlough - A furlough for any purpose other than a transfer furlough, and which may be defined based on its nature, as either emergency or routine, as follows:
(1) Emergency furlough - A furlough allowing an inmate to address a family crisis or other urgent situation as noted below at § 570.33(b).
(2) Routine furlough - A furlough for any of the reasons noted below at § 570.33 (a) and (c) through (j).
(c) Duration and distance of non-transfer furlough -
(1) Day furlough - A furlough within the geographic limits of the commuting area of the institution, which lasts 16 hours or less and ends before midnight.
(2) Overnight furlough - A furlough which falls outside the criteria of a day furlough.