The London protection and indemnity (P&I) Club has issued new guidance on measuring sea conditions, after it was inundated with inquiries from members.

The club said it has since received clearer guidance on the Douglas Scales for sea conditions from the World Meteorological Organisation. It said that while the Douglas Sea tables referred to the waves generated by the wind at a particular locality, the Douglas Swell tables measured decaying waves generated by distant winds.

The club said that shipowners, when conducting charter party negotiations, should differentiate between the two sets of tables.