Each employer shall preserve for at least 3 years:
(a) Payroll records. From the last date of entry, all payroll or
other records containing the employee information and data required
under any of the applicable sections of this part, and
(b) Certificates, agreements, plans, notices, etc. From their last
effective date, all written:
(1) Collective bargaining agreements relied upon for the exclusion
of certain costs under section 3(m) of the Act,
(2) Collective bargaining agreements, under section 7(b)(1) or
7(b)(2) of the Act, and any amendments or additions thereto,
(3) Plans, trusts, employment contracts, and collective bargaining
agreements under section 7(e) of the Act,
(4) Individual contracts or collective bargaining agreements under
section 7(f) of the Act. Where such contracts or agreements are not in
writing, a written memorandum summarizing the terms of each such
contract or agreement,
(5) Written agreements or memoranda summarizing the terms of oral
agreements or understandings under section 7(g) or 7(j) of the Act, and
(6) Certificates and notices listed or named in any applicable
section of this part.
(c) Sales and purchase records. A record of (1) total dollar volume
of sales or business, and (2) total volume of goods purchased or
received during
such periods (weekly, monthly, quarterly, etc.), in such form as the
employer maintains records in the ordinary course of business.