It has been brought to the notice of this Directorate that many
mariners are wrongly plotting Global Positioning System position on WGS 84
datum on Indian Navigational Charts in everest datum without applying
datum shift parameters/corrections.
2. All mariners are advised to exercise caution while plotting Global
Positioning System positions on the Indian Navigational charts, as Indian
Navigational Chart are referred to Everest datum & GPS positions are
referred to the WGS 84 datum. The
variation in these parameters is considerable along the coastal belt
including the Andaman & Nicobar and Lakshadweep islands (Range 300-800
metres.) Mariners are also
advised to apply datum shift parameters given on the charts or available
in ECDIS equipment before using Global Positioning System positions on
Indian Navigational charts. These
shift parameters, where observed are specified on the charts at suitable
position under legend note. Mariners
should also use alternate methods of fixing while operating in restricted
waters and in vicinity of dangers, especially where such datum shift
parameters/corrections are not listed.
3. Mariners using Indian Navigational Charts are hereby warned that
the Directorate General of Shipping or the Chief Hydrographer to the Govt.
of India shall not be responsible for any marine accidents arising as a
result of usage of GPS positions in WGS 84 datum, if plotted on aforesaid
Indian Navigational Charts without
the application of Datum Transformation Parameters/correction where
officially available or listed in the charts.
4. This issues with approval of the Nautical Adviser to the Govt. of