To determine the percentage of water absorption of bricks
A sensitive balance capable of weighing within 0.1% of the mass of the specimen and ventilated oven
Three numbers of whole bricks from samples collected for testing should be taken.
(I) Dry the specimen in a ventilated oven at a temperature of 105 °C to 115°C till it attains substantially constant mass.
(II) Cool the specimen to room temperature and obtain its weight () specimen too warm to touch shall not be used for this purpose .
(III) Immerse completely dried specimen in clean water at a temperature of 27+2°C for 24 hours.
(IV) Remove the specimen and wipe out any traces of water with damp cloth and weigh the specimen after it has been removed from water ().
Water absorption, % by mass, after 24 hours immersion in cold water in given by the formula,
The average of result shall be reported.
Water absorption of the given bricks = ………….%
When tested as above, the average water absorption shall not be more than 20% by weight up to class 125 and 15% by weight for higher class.