NGA 85 Meter Assembly And Abnormal Operating Conditions (AOCs) Practice Test

Liquids and particulates harm meters and regulators by contaminating and wearing the moving parts and the flow paths they rely on. When liquids appear in a gas stream, they can cause liquid slugging, corrosion or swelling of seals, and condensation that alters the effective flow and pressure relationships. This disrupts how a regulator senses pressure and how a meter records flow, leading to unstable, inaccurate operation or even failure to regulate properly. Particulates are abrasive and can erode gear trains, damage diaphragms and seals, and clog orifices and valve seats. This wear and blockage change clearances, create sticking or chattering, and introduce drift or erratic readings. Because meters and regulators depend on precise flow paths and smooth, repeatable movement, any contamination degrades performance, reduces accuracy, and can compromise safety. Therefore, liquids and particulates are detrimental because they cause wear and blockages in the components that determine measurement and regulation.