AOM-Aerodrome Operating Minima

Aerodrome operating minima (AOM) are criteria used by pilots to determine whether they may land or take off from any runway at night or in IMC (Instrument Meteorological Conditions). AOM consist of two parts: one relating to the cloud base and one relating to the visibility and/or Runway Visual Range (RVR).
AOM is defined as
"The limits of usability of an aerodrome for:
a) take-off, expressed in terms of RVR and/or visibility and, if necessary, cloud conditions;
b) landing in Precision Approach and landing operations, expressed in terms of visibility and/or RVR and Decision Altitude/Height (DA/H) as appropriate to the category of the operation;
c) landing in approach and landing operations with vertical guidance, expressed in terms of visibility and/or RVR and DA/H; and
d) landing in Non-Precision Approach and landing operations, expressed in terms of visibility and/or RVR, Minimum Descent Altitude/Height (MDA/H) and, if necessary, cloud conditions."
Take-off minima normally consist of a visibility and/or RVR element only and a flight is not permitted to commence take-off unless the weather conditions at the aerodrome of departure are equal to or better than the AOM specified for Take-off from the runway in use  and Landing at that aerodrome or at a suitable Alternate Aerodrome.
Landing minima consist of both visibility and/or RVR, and cloud base elements. An instrument approach may not be continued beyond the outer marker fix in the case of a precision approach or below 1,000 ft AGL in the case of a non-precision approach, unless the reported visibility or RVR is above the specified minimum. An instrument approach may not be continued beyond the DH/DA or MDH/MDA unless the required visual references for the runway are distinctly visible and identifiable.