Conducted annual backflow prevention device testing at commercial property in Rocky Mount. Site contains three devices: 2" Reduced Pressure Zone (RPZ) assembly on main domestic line, 4" Double Check Valve Assembly (DCVA) on fire suppression system, and 1" Pressure Vacuum Breaker (PVB) on irrigation system. Utilized calibrated differential gauge to perform testing according to NC AWWA standards. RPZ tested within acceptable parameters with relief valve functioning appropriately at 2 PSI differential. DCVA check valves tested at 3.2 PSI and 2.9 PSI respectively, exceeding minimum requirement of 1 PSI. PVB air inlet opened at 1.8 PSI as required. All test results documented electronically and submitted to water authority database. Applied appropriate certification tags to each device indicating test date and technician information. Recommended preventative maintenance program to facility manager to extend service life of devices. All devices certified compliant with no remedial action req