Exposure frost damage

Rain Penetration. The degree to which rain penetrates brickwork greatly affects the thermal insulation value and the resistance to frost damage. It depends on the integrity of the structure, the workmanship, as well as the porosity of the bricks and mortar. It is influenced by wind conditions and site exposure to driving rain. Test cabinets with water... 

Symptoms Exposure to PAN (peroxyacyl nitrate) causes a silvery glaze on the lower surfaces of leaves, resembling damage due to frost, sunscald, mites, thrips, or leafhoppers. Young, rapidly growing tissue is most sensitive to PAN injury. 

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