(1)(a) The plumbing contractor shall:

(i) Accurately report all plumbing hours worked by plumbing trainees and, effective June 30, 2021, report all plumbing trainee hours worked on a quarterly basis on a form prescribed by the department;

(ii) Attest that trainee hours were under the supervision of a certified plumber and within the proper ratio;

(iii) Provide the names and certification numbers of the supervising plumbers; and

(iv) Upon request, provide the department with trainee hours worked by all trainees within their employment for the past two-year period.

(b) Plumbing contractors are not required to identify which hours a trainee works with a specific certified plumber. Plumbing hours reported on all payroll reports for audit purposes will be considered work performed by a certified plumber or trainee working within ratio. Plumbing work reported for noncertified plumbers or supervision and ratio requirements is a violation of this chapter and subject to issuance of an infraction.

(2) The department may audit the records of a plumbing contractor that has verified the hours of experience submitted by a plumbing trainee to the department under RCW 18.106.030 in the following circumstances: Excessive hours were reported; hours were reported outside the normal course of the plumbing contractor's business; or for other similar circumstances in which the department demonstrates a likelihood of excessive or improper hours being reported. The department shall limit the audit to records necessary to verify hours. Failure to have or maintain payroll and other records for each employee performing plumbing work for the company is a violation of this chapter and subject to issuance of an infraction. The department may assess a penalty of up to five thousand dollars for failure to maintain adequate records. Records used to document plumbing work must be maintained for a minimum of three years. The department shall adopt rules implementing audit procedures. Information obtained from a plumbing contractor under the provisions of this section is confidential and is not open to public inspection under chapter 42.56 RCW.

(3) Violation of this section by a contractor is an infraction.