What are two conditions that can affect baseline CAZ pressure differential measurements?

Baseline CAZ (Conditioned Area Zone) pressure differential measurements can be influenced by several environmental and mechanical factors. The correct response highlights the impact of wind and a pinched reference hose on these measurements.

Wind can create fluctuations in pressure around the CAZ, affecting the readings by either increasing or decreasing pressure differentials depending on the wind direction and intensity. This is particularly relevant in residential settings where external environmental conditions can significantly alter indoor pressure zones.

A pinched reference hose can also critically impact the accuracy of pressure measurements. If the reference hose is obstructed or pinched, it may not allow for accurate pressure readings, leading to erroneous data about the CAZ pressure differential. This type of mechanical obstruction can arise from kinks in the hose or improper setup during testing, and it must be rectified to ensure valid measurements.

While the other potential responses regarding temperature differences, humidity levels, the presence of combustible gases, or factors like air conditioning use and heating system age do relate to building performance and indoor air quality, they do not directly influence the baseline CAZ pressure differential measurements in the same manner as wind conditions and mechanical integrity of the measurement equipment. Understanding these specific influences is crucial for accurate testing and assessment in building analysis practices.