The present invention provides elastomeric roof coatings and aqueous coating compositions of an acrylic emulsion copolymer that comprises a reductant and has a high molecular weight, a combination of a hydrophilic polymeric dispersant and a pigment, extender or filler, and a multivalent transition metal ion or multivalent transition metal ion compound or salt. A second module compares the total integrated area to a threshold integrated area and generates a pass status signal when the total integrated area is less than the threshold integrated area. Systems and other methods also are provided. The storage buffer includes a multiplicity of contiguous buffers, wherein each single bit buffer is associated with one of the contiguous buffers. The movable block is disposed on the limit knob and capable of moving to a predetermined position which is outside of the housing. By selecting the position of the tube relative to the optical signal emitter and optical signal receiver, the optical signal sensor can both detect pressure changes and provide an integrity check for both the functioning of the optical signal sensor and the placement of the tube.