8.11.2 Operating Conditions And Variability
Duty cycle, pulse structure, antenna scanning, beam steering, traffic loading, adaptive power control, and intermittent operation can cause the field at a location to vary over time. The result should identify whether it represents the conditions observed during the assessment, a typical condition, a prescribed operating state, or a specified maximum condition.
A short observation may not capture the relevant variation. Base-station and similar assessments may require a defined extrapolation to an actual-maximum condition, while radar and other pulsed sources may require separate evaluation against time-averaged and applicable brief-exposure restrictions. A peak-field restriction should be invoked only where the applicable standard and frequency range prescribe one. A low duty factor should not be used to dismiss a pulse-related requirement that the applicable standard assesses separately.
The operating state should be supported by evidence such as equipment settings, transmitter logs, network data, control-channel information, measured waveform characteristics, or a conservative assumption. Where future loading or operating modes could exceed the assessed condition, the conclusion must be limited accordingly or based on a justified maximum-case assessment.
8.11.3 Spatial Representativeness
RF fields can vary substantially over short distances because of antenna patterns, near-field gradients, standing waves, reflections, and shielding. A point maximum, an average over a defined area or volume, and a value representative of a person's occupied space are different results and should not be interchanged without justification.
The interpretation should follow the spatial averaging and sampling rules associated with the limit. A single local maximum should not be treated as a prescribed whole-body spatial average, and an average should not be used to conceal a local restriction. Where a screening method intentionally uses a conservative point value, that conservatism should be identified.
Accessible areas and likely body positions should be considered, including elevated work locations, maintenance positions, and places where a person could approach a source. Results for inaccessible locations can be useful for defining controls but should not be confused with normal public or worker exposure.