1.1 This standard describes the following methods of sub-division of gross sample down to the required quantity for further analysis for determination of particle size distribution:
a) Reduction by halving from over 1 500 to 500 litres,
b) Reduction by coning and quartering from 1 000 or less to 25 litres,
c) Reduction by turntable type sample divider from over 1 500 to 1 litre,
d) Reduction by slotted cone type sample divider from over 1 500 to 1 litre,
e) Reduction by large oscillating hopper type sample divider from 100 to 1 litre,
f) Reduction by grid type sample divider from 50 litres to 5 millilitres, and
g) Reduction by small oscillating hopper type sample divider from 1 litre to 0·2 millilitres.
IS 4879-1968 history
1969IS 4879-1968 Method for subdivision of total powder sample for determination of particle size