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Title 15 — Commerce and Trade

Chapter 6 — Weights and Measures and Standard Time

§ 261. Zones for standard time; interstate or foreign commerce

Statutory text

(a)

In general

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.

(b)

Coordinated Universal Time defined

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.

Footnotes

  1. 1 So in original. Probably should be followed by “by”.

Legislative history

Reconstructed from this section’s Code source credit and amendment notes, resolved against the local Statutes at Large. Editorial notes are evidence, not the law that made the change.

  1. Pub. L. 65–24 § 1 · 40 Stat. 102

    Enacted · 15 U.S.C. § 261

    Mar. 19, 1918, ch. 24, § 1, 40 Stat. 450

    Source evidence

    Code source credit
    Mar. 19, 1918, ch. 24, § 1, 40 Stat. 450

  2. Uniform Time Act of 1966

    Pub. L. 89–387 § 4(a) · 80 Stat. 107

    1. Inserted · 15 U.S.C. § 261

      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”

    2. Substituted · 15 U.S.C. § 261

      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, substituted “solar” for “astronomical” time, established the first zone on basis of the 60th degree of longitude west from Greenwich

    3. Redesignated · 15 U.S.C. § 261

      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, 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

    4. Redesignated · 15 U.S.C. § 261

      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, 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

    5. Substituted · 15 U.S.C. § 261

      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, substituted “interstate or foreign commerce” for “commerce between the several States and and with foreign nations” and defined “interstate or foreign commerce”

    Source evidence

    Code amendment note
    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”.

    Enacted provision · exact public law section
    (a) The first section of the Act of March 19, 1918, as amended (15 U.S.C. 261), is amended to read as follows: “That for the purpose of establishing the standard time of the United States, the territory of the United States shall be divided into eight zones in the manner provided in this section. Except as provided in section 3(a) of the Uniform Time Act of 1966, 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; and that of the eighth zone on the one hundred and sixty-fifth degree. The limits of each zone shall be defined by an order of the Interstate Commerce Commission, 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 “Interstate or foreign commerce.” be modified from time to time. As used in this Act, the term ‘interstate or foreign commerce’ means commerce between a State, the District of Columbia, the Common wealth of Puerto Rico, or any possession of the United States and any place outside thereof.”

  3. Pub. L. 97–449 § 2(c) · 96 Stat. 2413

    Substituted · 15 U.S.C. § 261

    Pub. L. 97–449 substituted “Secretary of Transportation” for “Interstate Commerce Commission”

    Source evidence

    Code amendment note
    Pub. L. 97–449 substituted “Secretary of Transportation” for “Interstate Commerce Commission”.

    Enacted provision · exact public law section
    (c) The Act of March 19, 1918 (15 U.S.C. 261–264), the Act of March 4, 1921 (15 U.S.C. 265), and the Uniform Time Act of 1966 (15 U.S.C. 260, 260a, 261–263, 266, 267) are amended by striking out the words “Interstate Commerce Commission” wherever they appear and substituting “Secretary of Transportation”.

  4. Pub. L. 106–564 § 1(a) · 114 Stat. 2811

    1. Substituted · 15 U.S.C. § 261

      Pub. L. 106–564, in first sentence, substituted “nine zones” for “eight zones” and, in second sentence

    2. Substituted · 15 U.S.C. § 261

      Pub. L. 106–564, in first sentence, substituted “; that of the eighth” for “; and that of the eighth”

    3. Inserted · 15 U.S.C. § 261

      Pub. L. 106–564, in first sentence, inserted before period at end “; and that of the ninth zone on the one hundred and fiftieth meridian of longitude east from Greenwich.”

    Source evidence

    Code amendment note
    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.”

    Enacted provision · exact public law section
    (a) In General.— The first section of the Act of March 19, 1918 (15 U.S.C. 261; commonly known as the Calder Act) is amended— (1) in the first sentence, by striking “eight zones” and inserting “nine zones”; and (2) in the second sentence— (A) by striking “; and that of the eighth” and inserting “; that of the eighth”; and (B) by inserting before the period the following: “; and that of the ninth zone on the one hundred and fiftieth meridian of longitude east from Greenwich.”.

  5. America COMPETES Act

    Pub. L. 110–69 title III § 3013(c)(3) · 121 Stat. 572

    1. Amended · 15 U.S.C. § 261

      Pub. L. 110–69 designated existing provisions as subsec. (a)

    2. Inserted · 15 U.S.C. § 261

      Pub. L. 110–69 inserted heading

    3. Substituted · 15 U.S.C. § 261

      Pub. L. 110–69 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..”

    4. Added · 15 U.S.C. § 261

      Pub. L. 110–69 added subsec. (b)

    Source evidence

    Code amendment note
    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).

    Enacted provision · exact public law section
    (3) Standard time.— Section 1 of the Act of March 19, 1918, (commonly known as the “Calder Act”) (15 U.S.C. 261) is amended— (A) by inserting “(a) In General.—” before “For the purpose”; (B) by striking the second sentence and the extra period after it and inserting “Except as provided in section 3(a) of the Uniform Time Act of 1966 (15 U.S.C. 260a), 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 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.”; and (C) by adding at the end the following: “(b) Coordinated Universal Time Defined.— 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.” .

13 of 14 references resolved to an enrolled provision · 1 partial

Editorial Notes

Amendments1966–2007 · 4 rounds

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.”

1983

Pub. L. 97–449 substituted “Secretary of Transportation” for “Interstate Commerce Commission”.

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”.

Statutory Notes and Related Subsidiaries

Short Title

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”.

Repeals

Section 5 of act , repealed all conflicting acts and parts of acts.

District of Columbia

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.

Return to Standard Time

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 , at 2:00 A.M.

Credits

1918–2007 · 5 acts
  1. 1918Mar. 19, 1918, ch. 24, § 1, 40 Stat. 450
  2. 1966Pub. L. 89–387, § 4(a), , 80 Stat. 108
  3. 1983Pub. L. 97–449, § 2(c), , 96 Stat. 2439
  4. 2000Pub. L. 106–564, § 1(a), , 114 Stat. 2811
  5. 2007Pub. L. 110–69, title III, § 3013(c)(3), , 121 Stat. 598.
Show as published

(Mar. 19, 1918, ch. 24, § 1, 40 Stat. 450; Pub. L. 89–387, § 4(a), , 80 Stat. 108; Pub. L. 97–449, § 2(c), , 96 Stat. 2439; Pub. L. 106–564, § 1(a), , 114 Stat. 2811; Pub. L. 110–69, title III, § 3013(c)(3), , 121 Stat. 598.)

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