1. 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 India.

Sd/-
(Capt. S.K. Shukla)
Nautical Surveyor