Drawings ~ these are the principal means of communication
between the designer, the builder and other parties to a contract.
Drawings should therefore be clear, accurate, contain all the
necessary information and be capable of being easily read.
Design practices have their own established symbols and notations
for graphical communication. Some of which are shown on this and
the next three pages. Other guidance can be found in BS EN ISOs
4157 and 7519.Drawings---Hatchings, Symbols and Notations