(. measurement standard) ( ), () .
(. primary standard) , ( ) .
, ( , , , , ..).
(. secondary standard) , .
. -, .
(. transfer standard) , , .
(. reference standard) , ( , , (), , ), .
- , .
. - .
(. working standard) , .
, .
. , , , , , , , , , .
(. national standard) , .
(. international standard) , , .
. , , 1- ().