In the standard forms of specifications such tests as are considered 
necessary have been included, but, as a rule, specific test limits have 
not been recommended, owing to recognition of the fact that no one 
set of test limits could cover satisfactorily the wide differences in 
methods of construction, available materials, and local conditions 
peculiar to the various parts of the country. It is expected that 
engineers who adopt the recommended forms of specifications will 
insert such test limits as they consider advisable for any given work. 
Under standard methods of testing references only are given for 
description of tests which are published in readily available form. 
This is also true of the methods of sampling. 
Logan Waller Page, 
Director Office of Public Roads and Rural Engineering. 
