Test for Presence of Soluble Salts

Soluble salts if present in the brick cause efflorescence. Presence of such salts can be determined as follows:

Place on the ends the bricks in 25 mm depth of water in a dish of minimum diameter 150 mm and depth 30 mm. The dish is made of glass and porcelain or of glazed stone work. The experiment is performed in a well-ventilated room among "20 to 30^oC" till all the water in the dish is either absorbed through the specimen or is evaporated. After the specimens have dried add same quantity of water to the dish and let it too be absorbed through the specimen for efflorescence after the second evaporation. Presence of efflorescence should be categorized as nil, slight, moderate, heavy or serious as described below:

Nil

While the deposit of efflorescence is imperceptible.

Slight

While the deposit of efflorescence does not cover more than 10% of the exposed area of the brick.