If your station lacks runway visual range equipment and the visibility is down to one quarter mile, how is the RVR coded in the report?

In the absence of runway visual range (RVR) equipment at a station, the reporting regulations specify that no RVR should be coded in the observation report if visibility is down to a quarter mile. This aligns with standard aviation weather reporting practices that require specific equipment to accurately determine and report RVR values. When RVR equipment isn't available, the observation report simply omits this element rather than providing an estimation that could lead to confusion or misinterpretation about the visibility conditions on the runway. Therefore, not coding any RVR indicates to pilots and other users of the reports that the measurement was not obtained due to lack of equipment, maintaining clarity of the conditions at the station.