Testing plastic mortar can help ensure its performance before it's placed in the wall. WHAT CAN BE TESTED Consistency or workability, air content, water retention, and mix proportions can be measured to determine whether the mortar materials proposed for a project will perform as required. The specifier should focus on measuring mortar performance before construction by using the test methods described in ASTM C 270 and C 780. LAB TESTING FOR ASTM C 270 For ASTM C 270, mortar consistency is measured using a flow table. This test provides information on water demand for various mortars and establishes a basis for determining mortar strength and water retention for ASTM C 270. The water retention test shows the ability of a mortar to retain its mixing water after being suctioned by a device that simulates an absorptive masonry unit. FIELD TESTING PLASTIC MORTARS The main difference between field mortar and ASTM C 270 laboratory mortar is the water content. The properties of mortars produced with the consistency required for actual construction are measured using tests described in ASTM C 780. The consistency of field mortars can be measured using a cone penetrometer as described in ASTM C 780, Annex A.1. The air content of field mortars can be measured two ways: by the pressure method using a pressure meter, or the volumetric method using a "roll-o-meter" as described in ASTM C 780 Annex A.6. The unit weight of field mortar can be measured using a volume-calibrated bucket and a scale. A method for measuring board life is described in ASTM C 780, Annex A.3. This method determines the time required for mortar to change from an initial penetration resistance considered good for masonry construction to one that is unacceptable.