To determine the fineness of cement, pozzolanas and other powdery materials, various international specifications recommend the use of "specific area" method. In the methods described below, air permeability methods are used to determine the specific surface as total surface area in cm²/g of material.
Milestone Instruments

Air Permeability Apparatus Blaine Type
Meets:- IS: 5516 IS: 1727, IS: 4031, IS: 4825, ASTM C204, BS: 4359 Part 2
It is a variable flow type air permeability apparatus.
The apparatus comprises one each of:
Permeability Cell, 12.5 mm ID
'U' Tube Manometer, mounted on stand
Perforated Metal Disc
Plunger
Rubber Stopper
Rubber Tube, 20 cm long
Filter Paper Discs (Twelve Nos.)
Dibutylphthalate Liquid Extras Punch