ABSTRACT
It was traditional British practice, in adjusting claims for the cost of repairs to ship, both for general and particular average, to apply a very simple set of deductions to the cost of repairs in all cases where old material had been replaced by new. The custom to apply these deductions to the cost of repairs was given judicial approval in 1879. With the introduction of iron and steel ships, it became apparent that the customary deductions were altogether too severe, and in 1884 the Association of Average Adjusters set up a committee to take technical advice and recommend a progressive scale of deductions depending upon the age of the ship. Ships are now built for trading within an expected lifetime, typically 20 or 25 years, and virtually all parts of the ship, other than such items as are clearly recognised to be subject to wear and tear or deterioration, are constructed to last for that length of time.
