ILS – Instrument Landing System Approach Minima for different categories of approaches are as follows:
| Categories | Decision Height | RVR/Visibility |
| Category I | not lower than 60m (200 ft) | not less than 550m (visibility) and 800m (RVR) |
| Category II | lower than 60m (200 ft) but not lower than 30m (100 ft) | RVR not less than 300m |
| Category III – A | lower than 30m (100 ft) or no decision height | RVR not less than 175m |
| Category III – B | lower than 15m (50 ft) or no decision height | RVR less than 175 m but not less than 50m |
| Category III – C | no decision height limitations | no RVR limitations |
Mid zone and Roll-out zone RVR requirements for different category of approaches:
Touch-down zone RVR needs to be reported for Cat I operations, touch-down and mid zone RVR for Cat II operations, touch-down, mid and roll-out zone RVR for Cat III operations.
Touch-down zone is always the controlling however if any other RVR is reported and is relevant it also becomes controlling.
| Type of operation | RVR | ||
| Touch-down zone | Mid zone | Roll-out zone | |
| CAT I | 550 m | 125 m | 125 m |
| CAT II | 300 m | 125 m | 125 m |
| CAT III A | 175 m | 125 m | 125 m |
| CAT III B | 75/50 m | 75/50 m | 75/50 m |
