TM,
http://www.casa.gov.au/wcmswr/_asset...m/011r0719.pdf
That is part of the the "Air Operator Certification Manual" for "Other than High Capacity RPT, Initial Issue of AOC".....
Your ops manual or similar document would probably contain a section on Aircraft Landing Minima and Aerodrome Operating Minima etc.
7.19.1.1 Precision Approaches
For precision approaches, the published DA or DH has incorporated, for each category of
aircraft, an allowance for the height that aircraft will descend below the decision altitude or
height, after a pilot has decided to initiate a ‘missed approach’. The actual height loss will
depend, in addition to inertia, on factors such as the skill and training of the pilot, physical
characteristics of the aircraft (distance between the wheels and the glide-path antenna),
and altimeter or other instrument errors.
For Cat I operations involving small- to medium-size aircraft, the addition of altimeter
pressure error should produce an acceptable ALM.
Note:
Altimeter pressure error for various aircraft configurations is commonly given in
the aircraft Flight Manual.
Where altimeter pressure error is not known, the addition of 50 ft to DA is approved by AIP
DAP as an acceptable procedure.
Hope that helps in some way.