OPS 1.405
Commencement and continuation of approach
(a) The commander or the pilot to whom conduct of the flight has been delegated may commence an instrument approach
regardless of the reported RVR/Visibility but the approach shall not be continued beyond the outer marker, or equivalent
position, if the reported RVR/visibility is less than the applicable minima (see OPS 1.192).
(b) Where RVR is not available, RVR values may be derived by converting the reported visibility in accordance with Appendix
1 to OPS 1.430, subparagraph (h).
(c) If, after passing the outer marker or equivalent position in accordance with (a) above, the reported RVR/visibility falls
below the applicable minimum, the approach may be continued to DA/H or MDA/H.
(d) Where no outer marker or equivalent position exists, the commander or the pilot to whom conduct of the flight has
been delegated shall make the decision to continue or abandon the approach before descending below 1 000 ft above
the aerodrome on the final approach segment. If the MDA/H is at or above 1 000 ft above the aerodrome, the operator
shall establish a height, for each approach procedure, below which the approach shall not be continued if RVR/visibility
is less than applicable minima.
(e) The approach may be continued below DA/H or MDA/H and the landing may be completed provided that the required
visual reference is established at the DA/H or MDA/H and is maintained.