If transmissometer readings are converted into RVRs using computers, the RVR is usually presented automatically in the aerodrome control tower and approach control office using digital displays; similar displays are installed in the MET office or observing station (e.g. USA).
Tables may be used to convert the transmission factor into an RVR value. This is usually done in the meteorological observing station which then transmits the RVR reports to the users by telephone, telewriter, pneumatic tube, etc.
It will be understood that all systems used, which are not automated, give a certain time-delay in the availability of the the current RVR report. Most authorities have taken steps to keep this time-delay as short as possible.
Source: FCRG
See also:
1. Horizontal visibility aspects
2. Visual range
3. Observing techniques of RVR
4. Observing of RVR
5. Availability of RVR observations at ATS units
6. Reporting procedures of RVR reports
7. Accuracy of RVR reports
8. Slant visual range
9. The visual segment
10. Variation in visual segment
11. Flight visibility and vision at high altitudes