2 U.S.C. § 182b

1. (a)There is hereby established in the Treasury a revolving fund for the following programs and activities of the Librarian:
   1. (1)Decimal classification development.
   2. (2)The operation of a gift shop or other sales of items associated with collections, exhibits, performances, and special events of the Library of Congress.
   3. (3)Document reproduction and microfilming services.
   4. (4)Special events and programs.
   5. (5)Training.
2. (b)A separate account shall be maintained in the revolving fund under this section with respect to the programs and activities described in each of the paragraphs of subsection (a).
3. (c)The Librarian may charge a fee for services under any of the programs and activities described in subsection (a), and shall deposit any such fees charged into the account of the revolving fund under this section for such program or activity.
4. (d)
   1. (1)Each account of the revolving fund under this section shall consist of the following amounts:
      1. (A)Amounts deposited by the Librarian under subsection (c).
      2. (B)Any other amounts received by the Librarian which are attributable to the programs and activities covered by such account.
      3. (C)Amounts deposited by the Librarian under paragraph (2).
      4. (D)Such other amounts as may be appropriated under law.
   2. (2)The Librarian shall transfer to each account of the revolving fund under this section the following:
      1. (A)Any obligated, unexpended balances existing as of the date of the transfer which are attributable to the programs and activities covered by such account.
      2. (B)An amount equal to the difference as of such date between—
         1. (i)the total value of the supplies, inventories, equipment, gift fund balances, and other assets attributable to such programs and activities; and
         2. (ii)the total value of the liabilities attributable to such programs and activities.
5. (e)
   1. (1)Except as provided in paragraph (2), amounts in the accounts of the revolving fund under this section shall be available to the Librarian, in amounts specified in appropriations Acts and without fiscal year limitation, to carry out the programs and activities covered by such accounts.
   2. (2)In the case of any amount in the revolving fund consisting of a payment received for services of the United States Capitol Police in connection with a special event or program described in subsection (a)(4), the Librarian shall transfer such amount upon receipt to the Capitol Police for deposit into the applicable appropriations accounts of the Capitol Police.