River Clyde Fisheries Management Trust Ltd.
 

This distress signal is for use ONLY where there is grave and imminent danger
to a vessel or person.

The spoken words -

MAYDAY  MAYDAY  MAYDAY

This is - give vessels name, three times, followed immediately by  MAYDAY (once)

Give position with latitude and longtitude or from a named spot.

Nature of distress / Assistance required / Number of people on board

The following is for when help may be needed, but the danger is not grave and imminent.

PAN PAN   PAN PAN   PAN PAN

Hello all stations - Hello all stations - Hello all stations

This is - give vessels name, spoken three times.

Position as for MAYDAY, nature and assistance.

SECURITE   (Say-cure-e-tay)

SECURITE - the Safety signal - repeated three times (usually by a coastal station) 
indicates that an important navigational or meteorological warning will follow. 
Eg. a severe weather warning or a bouy out of position.