PDFWAC 16-202-2014
What are alternative methods for metering?
Alternative technology used for metering product must fulfill the provisions of this chapter.
A person may function as a metering device with a nonpressurized irrigation delivery system. However, the individual must remain on-site to continuously monitor the application and be immediately available to terminate the application in the event of equipment malfunction. The person must be knowledgeable about the operation of the irrigation and injection systems.