Measurement Quality Tables
To ensure that all FIA observations are made to the highest standards possible, a regular program of quality control and quality assurance is an integral part of all FIA data collection efforts. This program begins with the documentation of protocols and procedures used in the inventory followed by extensive crew training. To assess the quality of the data collected by these trained crews, a random sample of at least 4 percent of all plots are measured independently by a different qualified crew. These independent measurements are referred to as blind checks. The purpose of these blind checks is to assess the quality of field measurements. The second measurement on these blind check plots is done by a crew termed the QA crew. In all cases, QA crews have as much or more experience and training in FIA field measurements that those of the standard FIA crews.
The quality of field measurements is assessed nationally through a set of measurement quality objectives (MQO's) that are set for every data item FIA collects. Each MQO consists of two parts; a tolerance or acceptable level of measurement error, and an objective in terms of the percent of measurements within tolerance. The blind check measurements are used to observe how often individual field crews are meeting these objectives and to assess the overall compliance among all crews. The tables here report the compliance rates for various measurements on phase 2 and phase 3 plots FIA plots.