Source: http://uscode.house.gov/view.xhtml?req=granuleid%3AUSC-prelim-title15-chapter6-subchapter9&saved=%7CKHRpdGxlOjE1IHNlY3Rpb246MjYwYSBlZGl0aW9uOnByZWxpbSkgT1IgKGdyYW51bGVpZDpVU0MtcHJlbGltLXRpdGxlMTUtc2VjdGlvbjI2MGEp%7CdHJlZXNvcnQ%3D%7C%7C0%7Cfalse%7Cprelim&edition=prelim
Timestamp: 2019-04-19 04:20:35+00:00

Document:
1983—Pub. L. 97–449 substituted "Secretary of Transportation" for "Interstate Commerce Commission".
Pub. L. 89–387, §6, Apr. 13, 1966, 80 Stat. 108, provided that: "This Act [enacting this section and sections 260a, 266, and 267 of this title and amending sections 261 to 263 of this title] shall take effect on April 1, 1967; except that if any State, the District of Columbia, the Commonwealth of Puerto Rico, or any possession of the United States, or any political subdivision thereof, observes daylight saving time in the year 1966, such time shall advance the standard time otherwise applicable in such place by one hour and shall commence at 2 o'clock antemeridian on the last Sunday in April of the year 1966 and shall end at 2 o'clock antemeridian on the last Sunday in October of the year 1966."
Pub. L. 89–387, §1, Apr. 13, 1966, 80 Stat. 107, provided: "That this Act [enacting this section and sections 260a, 266, and 267 of this title and amending sections 261 to 263 of this title] may be cited as the &apos;Uniform Time Act of 1966&apos;."
During the period commencing at 2 o'clock antemeridian on the second Sunday of March of each year and ending at 2 o'clock antemeridian on the first Sunday of November of each year, the standard time of each zone established by sections 261 to 264 of this title, as modified by section 265 of this title, shall be advanced one hour and such time as so advanced shall for the purposes of such sections 261 to 264, as so modified, be the standard time of such zone during such period; however, (1) any State that lies entirely within one time zone may by law exempt itself from the provisions of this subsection providing for the advancement of time, but only if that law provides that the entire State (including all political subdivisions thereof) shall observe the standard time otherwise applicable during that period, and (2) any State with parts thereof in more than one time zone may by law exempt either the entire State as provided in (1) or may exempt the entire area of the State lying within any time zone.
It is hereby declared that it is the express intent of Congress by this section to supersede any and all laws of the States or political subdivisions thereof insofar as they may now or hereafter provide for advances in time or changeover dates different from those specified in this section.
For any violation of the provisions of this section the Secretary of Transportation or his duly authorized agent may apply to the district court of the United States for the district in which such violation occurs for the enforcement of this section; and such court shall have jurisdiction to enforce obedience thereto by writ of injunction or by other process, mandatory or otherwise, restraining against further violations of this section and enjoining obedience thereto.
2005—Subsec. (a). Pub. L. 109–58 substituted "second Sunday of March" for "first Sunday of April" and "first Sunday of November" for "last Sunday of October".
1986—Subsec. (a). Pub. L. 99–359 substituted "first Sunday of April" for "last Sunday of April".
1983—Subsec. (c). Pub. L. 97–449 substituted "Secretary of Transportation or his" for "Interstate Commerce Commission or its".
1972—Subsec. (a). Pub. L. 92–267 authorized any State with parts thereof lying in more than one time zone to exempt by law that part of such State lying within any time zone from provisions of this subsection providing for advancement of time.
Pub. L. 109–58, title I, §110(b), Aug. 8, 2005, 119 Stat. 615, provided that: "Subsection (a) [amending this section] shall take effect 1 year after the date of enactment of this Act [Aug. 8, 2005] or March 1, 2007, whichever is later."
Pub. L. 99–359, §2(e), July 8, 1986, 100 Stat. 765, provided that: "This section [amending this section and enacting provisions set out as notes below] shall take effect 60 days after the date of enactment of this Act [July 8, 1986], except that if such effective date occurs in any calendar year after March 1, this section shall take effect on the first day of the following calendar year."
"(c) Report to Congress.—Not later than 9 months after the effective date stated in subsection (b) [set out above], the Secretary [of Energy] shall report to Congress on the impact of this section [amending this section] on energy consumption in the United States.
"(d) Right to Revert.—Congress retains the right to revert the Daylight Saving Time back to the 2005 time schedules once the Department [of Energy] study is complete."
"(4) that the use of daylight saving time over an expanded period could have other beneficial effects on the public interest, including the reduction of crime, improved traffic safety, more daylight outdoor playtime for the children and youth of our Nation, greater utilization of parks and recreation areas, expanded economic opportunity through extension of daylight hours to peak shopping hours and through extension of domestic office hours to periods of greater overlap with the European Economic Community."
shall be held and considered to remain in effect as the exercise by that State of the exemption permitted by such Act [see 15 U.S.C. 260a(a)] unless that State, by law, provides that such exemption shall not apply."
"(1) Notwithstanding any other law or any regulation issued under any such law, the Federal Communications Commission shall, consistent with any existing treaty or other agreement, make such adjustment by general rules, or by interim action pending such general rules, with respect to hours of operation of daytime standard amplitude modulation broadcast stations, as may be consistent with the public interest, including the public's interest in receiving interference-free service.
"(2) Such general rules, or interim action, may include variances with respect to operating power and other technical operating characteristics.
"(3) Subsequent to the adoption of such general rules, they may be varied with respect to particular stations and areas because of the exigencies in each case."
Pub. L. 93–182, Dec. 15, 1973, 87 Stat. 707, as amended by Pub. L. 93–434, Oct. 5, 1974, 88 Stat. 1209, enacted the Emergency Daylight Saving Time Energy Conservation Act of 1973, which extended daylight saving time. The act was effective at 2 a.m. on the fourth Sunday which occurred after Dec. 15, 1973 and terminated at 2 a.m. on the last Sunday of April 1975.
Section 1. The Secretary of Transportation (hereinafter "the Secretary") is hereby designated and empowered to exercise the authority vested in me by section 3(b) of the Act [formerly set out above] to grant an exemption from section 3(a) of the Act (which establishes daylight saving time as standard time), or a realignment of a time zone limit, pursuant to a proclamation of a Governor of a State finding that the exemption or realignment is necessary to avoid undue hardship or to conserve fuel in the State or a part thereof.
Sec. 2. In deciding to grant or deny an exemption or realignment, the Secretary shall consider, among other things, the policy of the United States, as expressed in sections 2 and 4 of the Uniform Time Act of 1966 (80 Stat. 107, 108; 15 U.S.C. 260, 261), to promote the adoption and observance of uniform time within the standard time zones of the United States and the convenience of commerce, as well as possible energy savings, undue hardship to large segments of the population, and the possible impact on the success of and cooperation with the national energy conservation program.
Sec. 3. In carrying out his responsibilities under this order, the Secretary shall, as he deems necessary, consult with the Department of Health, Education, and Welfare, the Federal Energy Office (or any agency which hereafter may succeed to its functions), and any other interested agency and he may call upon those agencies for information and advice. Each interested department or agency shall assist the Secretary, as necessary, to carry out the provisions of this order.
For the purpose of establishing the standard time of the United States, the territory of the United States shall be divided into nine zones in the manner provided in this section. Except as provided in section 260a(a) of this title, the standard time of the first zone shall be Coordinated Universal Time retarded by 4 hours; that of the second zone retarded by 5 hours; that of the third zone retarded by 6 hours; that of the fourth zone retarded by 7 hours; that of the fifth zone retarded 1 8 hours; that of the sixth zone retarded by 9 hours; that of the seventh zone retarded by 10 hours; that of the eighth zone retarded by 11 hours; and that of the ninth zone shall be Coordinated Universal Time advanced by 10 hours. The limits of each zone shall be defined by an order of the Secretary of Transportation, having regard for the convenience of commerce and the existing junction points and division points of common carriers engaged in interstate or foreign commerce, and any such order may be modified from time to time. As used in sections 261 to 264 of this title, the term "interstate or foreign commerce" means commerce between a State, the District of Columbia, the Commonwealth of Puerto Rico, or any possession of the United States and any place outside thereof.
In this section, the term "Coordinated Universal Time" means the time scale maintained through the General Conference of Weights and Measures and interpreted or modified for the United States by the Secretary of Commerce in coordination with the Secretary of the Navy.
2007—Pub. L. 110–69 designated existing provisions as subsec. (a), inserted heading, substituted second sentence for former second sentence which read as follows: "Except as provided in section 260a(a) of this title, the standard time of the first zone shall be based on the mean solar time of the sixtieth degree of longitude west from Greenwich; that of the second zone on the seventy-fifth degree; that of the third zone on the ninetieth degree; that of the fourth zone on the one hundred and fifth degree; that of the fifth zone on the one hundred and twentieth degree; that of the sixth zone on the one hundred and thirty-fifth degree; that of the seventh zone on the one hundred and fiftieth degree; that of the eighth zone on the one hundred and sixty-fifth degree; and that of the ninth zone on the one hundred and fiftieth meridian of longitude east from Greenwich..", and added subsec. (b).
2000—Pub. L. 106–564, in first sentence, substituted "nine zones" for "eight zones" and, in second sentence, substituted "; that of the eighth" for "; and that of the eighth" and inserted before period at end "; and that of the ninth zone on the one hundred and fiftieth meridian of longitude east from Greenwich."
1966—Pub. L. 89–387 increased the number of time zones from five for the territory of continental United States to eight for the territory of the United States, inserted the "exception phrase", substituted "solar" for "astronomical" time, established the first zone on basis of the 60th degree of longitude west from Greenwich, redesignated as the second through the fifth zones based on the 75th, 90th, 105th, and 120th degrees former zones one through four based on such degrees, established the sixth zone based on the 135th degree, redesignated as the seventh zone based on the 150th degree former fifth zone based on such degree, and established the eighth zone based on the 165th degree, substituted "interstate or foreign commerce" for "commerce between the several States and and with foreign nations" and defined "interstate or foreign commerce".
Act Mar. 19, 1918, ch. 24, 40 Stat. 450, as amended, which is classified to sections 261 to 264 of this title, is popularly known as the "Calder Act".
Section 5 of act Mar. 19, 1918, repealed all conflicting acts and parts of acts.
Act Mar. 31, 1949, ch. 43, 63 Stat. 29, authorized the Board of Commissioners [now the Council of the District of Columbia] to establish daylight-saving time in the District of Columbia.
Act Sept. 25, 1945, ch. 388, 59 Stat. 537, provided, that, notwithstanding the provisions of act Jan. 20, 1942, ch. 7, 56 Stat. 9, which provided for war time, the standard time for each zone as provided for in sections 261 to 264 of this title should again become effective as of Sept. 30, 1945, at 2:00 A.M.
1 So in original. Probably should be followed by "by".
1966—Pub. L. 89–387 inserted "insofar as practicable (as determined by the Interstate Commerce Commission)" in two places and substituted "engaged in interstate or foreign commerce" for "engaged in commerce between the several States or between a State and any one of the Territories of the United States, or between a State or the Territory of Alaska and any one of the insular possessions of the United States or any foreign country".
The standard time of the first zone shall be known and designated as Atlantic standard time; that of the second zone shall be known and designated as eastern standard time; that of the third zone shall be known and designated as central standard time; that of the fourth zone shall be known and designated as mountain standard time; that of the fifth zone shall be known and designated as Pacific standard time; that of the sixth zone shall be known and designated as Alaska standard time; that of the seventh zone shall be known and designated as Hawaii-Aleutian standard time; that of the eighth zone shall be known and designated as Samoa standard time; and that of the ninth zone shall be known as Chamorro standard time.
2000—Pub. L. 106–564 struck out "and" before "that of the eighth" and inserted before period at end "; and that of the ninth zone shall be known as Chamorro standard time".
1983—Pub. L. 98–181 substituted "Alaska" for "Yukon", "Hawaii-Aleutian" for "Alaska-Hawaii", and "Samoa" for "Bering".
1966—Pub. L. 89–387 added Atlantic standard time as first zone designation; redesignated as eastern standard time, central standard time, mountain standard time and Pacific standard time for second through fifth zones former designation of United States standard eastern time, United States standard central time, United States standard mountain time and United States standard Pacific time for former zones one through four; added Yukon standard time as sixth zone designation; redesignated as Alaska-Hawaii standard time for seventh zone former designation of United States standard Alaska time for fifth zone; and added Bering standard time as eighth zone designation.
"(1) Any reference to Yukon standard time in any law, regulation, map, document, record, or other paper of the United States shall be held and considered to be a reference to Alaska standard time.
"(2) Any reference to Alaska-Hawaii standard time in any law, regulation, map, document, record, or other paper of the United States shall be held and considered to be a reference to Hawaii-Aleutian standard time.
"(3) Any reference to Bering standard time in any law, regulation, map, document, record, or other paper of the United States shall be held and considered to be a reference to Samoa standard time."
In the division of territory, and in the definition of the limits of each zone, as provided in sections 261 to 264 of this title, so much of the State of Idaho as lies south of the Salmon River, traversing the State from east to west near forty-five degrees thirty minutes latitude, shall be embraced in the fourth zone: Provided, That common carriers within such portion of the State of Idaho may conduct their operations on Pacific time.
The original section 3 of act Mar. 19, 1918, providing for daylight-savings, was repealed by act Aug. 20, 1919, ch. 51, 41 Stat. 280.
2007—Pub. L. 110–69 substituted "fourth zone" for "third zone".
1948—Act June 24, 1948, inserted proviso relating to common carriers.
Act June 24, 1948, ch. 631, §2, 62 Stat. 646, provided that: "This Act [amending this section] shall take effect at 2 o'clock antemeridian of the second Monday following the date of its enactment."
The Panhandle and Plains sections of Texas and Oklahoma are transferred to and placed within the United States standard central-time zone.
Beginning at a point where such western boundary time zone line crosses the State boundary line between Kansas and Oklahoma; thence westerly along said State boundary line to the northwest corner of the State of Oklahoma; thence in a southerly direction along the west State boundary line of Oklahoma and the west State boundary line of Texas to the southeastern corner of the State of New Mexico; thence in a westerly direction along the State boundary line between the States of Texas and New Mexico to the Rio Grande River; thence down the Rio Grande River as the boundary line between the United States and Mexico: Provided, That the Chicago, Rock Island and Gulf Railway Company and the Chicago, Rock Island and Pacific Railway Company may use Tucumcari, New Mexico, as the point at which they change from central to mountain time and vice versa; the Colorado Southern and Fort Worth and Denver City Railway Companies may use Sixela, New Mexico, as such changing point; the Atchison, Topeka and Santa Fe Railway Company and other branches of the Santa Fe system may use Clovis, New Mexico, as such changing point, and those railways running into or through El Paso may use El Paso as such point: Provided further, That this section shall not, except as herein provided, interfere with the adjustment of time zones as established by the Secretary of Transportation.
Section 2 of act Mar. 4, 1921, repealed all conflicting laws and parts of laws.
Pub. L. 91–228, Apr. 10, 1970, 84 Stat. 119, provided: "That, notwithstanding the first section of the Act of March 4, 1921 (15 U.S.C. 265), the Secretary of Transportation may, upon the written request of the County Commissioners Court of El Paso County, Texas, change the boundary line between the central standard time zone and the mountain standard time zone, so as to place El Paso County in the mountain standard time zone, in the manner prescribed in section 1 of the Act of March 19, 1918, as amended (15 U.S.C. 261), and section 5 of the Act of April 13, 1966 (15 U.S.C. 266). In the same manner, the Secretary of Transportation may also place Hudspeth County, Texas, in the mountain standard time zone, if the Hudspeth County Commissioners Court so requests in writing and if El Paso County is to be placed in that time zone."
Subchapter II of chapter 5, and chapter 7, of title 5 shall apply to all proceedings under this Act, sections 261 to 264 of this title, and section 265 of this title.
This Act, referred to in text, is Pub. L. 89–387, Apr. 13, 1966, 80 Stat. 107, as amended, known as the "Uniform Time Act of 1966". For complete classification of this Act to the Code, see Short Title note set out under section 260 of this title and Tables.
"Subchapter II of chapter 5, and chapter 7, of title 5" substituted in text for "The Administrative Procedure Act (5 U.S.C. 1001–1011)" on authority of Pub. L. 89–554, §7(b), Sept. 6, 1966, 80 Stat. 631, the first section of which enacted Title 5, Government Organization and Employees.
As used in this Act, the term "State" includes the District of Columbia, the Commonwealth of Puerto Rico, Guam, the Commonwealth of the Northern Mariana Islands, or any possession of the United States.
This Act, referred to in text, is Pub. L. 89–387, Apr. 13, 1966, 80 Stat. 107, known as the "Uniform Time Act of 1966". For complete classification of this Act to the Code, see Short Title note set out under section 260 of this title and Tables.
2000—Pub. L. 106–564 inserted "Guam, the Commonwealth of the Northern Mariana Islands," after "Puerto Rico,".

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