The watts 994hmb fire hydrant backflow preventer meter meets or exceeds registration accuracy for the low flow rate , normal operating flow rate , and maximum continuous operation flow rate as specifically stated in awwa standard c701 美國瓦茨994hmb消防栓防回流閥儀表滿足或優(yōu)于美國自來水廠協(xié)會( awwa ) c701標準規(guī)定的最小流量、正常工作流量和最大持續(xù)工作流量的記錄精度。