Certified Landscape Irrigation Auditor Practice Exam

Pilot tubes are used in irrigation systems to measure water levels or pressure and can be critical for determining system performance and efficiency. The accuracy of these devices may be compromised under several conditions, one of which relates to the characteristics of the water as it interacts with the irrigation equipment.

When sprinklers have spray diffusers, the water is distributed more finely and can create a different pattern of pressure and flow. This could lead to uneven distribution and effects on water pressure measurements. The fine mist or droplets created by diffusers can disrupt the consistent pressure readings that pilot tubes rely on to give accurate data.

In contrast, low water pressure generally affects the entire irrigation system but does not specifically compromise the integrity of pilot tubes; old equipment may present reliability issues, but not necessarily due to the basic function of pilot tubes; and irrigation scheduled at night typically does not affect the operation of pilot tubes, as long as the system is functioning correctly. Thus, the condition involving spray diffusers directly relates to how the water's distribution and behavior can affect the pilot tube readings.