This chapter becomes effective on April 23, 2018. Employers must comply with obligations of this chapter in accordance with the following:

(1) For occupational exposures to respirable crystalline silica in construction work, employers must comply with all obligations of this chapter by October 1, 2018. This includes the sample analysis requirement.

(2) For all occupational exposures to respirable crystalline silica other than construction work, employers must comply with this chapter by July 1, 2019, except as follows:

(a) Where employee exposure to respirable crystalline silica is above the PEL for thirty or more days per year medical surveillance requirements in WAC 296-840-145 must be complied with by July 1, 2019.

(b) Where employee exposure to respirable crystalline silica is at or above the action level for thirty or more days per year medical surveillance requirements in WAC 296-840-145 must be complied with by June 23, 2020.

(c) For hydraulic fracturing operations in the oil and gas industry, obligations for engineering controls under WAC 296-840-120(1) begin July 1, 2022.