A. Damusis, Sealants, Van Nostrand Reinhold Company, New York. Protective and decorative coatings generally employed in building are the following: Oil Paint. Drying-oil vehicles or binders plus opaque and extender pigments. Water Paint. Pigments plus vehicles based on water, casein, protein, oil emulsions, and rubber or resin latexes, separately or in combination. Calcimine. Water and glue, with or without casein, plus powdered calcium carbonate and any desired colored pigments. Varnish. Transparent combination of drying oil and natural or synthetic resins. Enamel. Varnish vehicle plus pigments. Lacquer. Synthetic-resin film former, usually nitrocellulose, plus plasticizers, volatile solvents, and other resins. Shellac. Exudations of the lac insect, dissolved in alcohol. Japan. Solutions of metallic salts in drying oils, or varnishes containing asphalt and opaque pigments. Aluminum Paint. Fine metallic aluminum flakes suspended in drying oil plus resin, or in nitrocellulose. Following are descriptions of the most commonly used vehicles and binders for

Local and national codes will dictate which electrical systems are required to be served by an emergency power system. NFPA 101, Life Safety Code, and NFPA 99, Health Care Facilities, and NFPA 110, Emergency and Standby Power Systems, published by the National Fire Protection Association, contain specific definitions of required emergency power loads but, in general, they include the following: Emergency systems, including emergency and egress (exit) lighting, essential ventilation systems, fire detection and alarm systems, elevators, fire pumps, public safety communications systems, and industrial processes where interruption could cause life safety risk. Power must be restored to these loads in not less than 10 s (or less, depending on local codes). Legally-required standby systems, including heating and refrigeration systems, communications systems, ventilation and smoke removal systems, sewage disposal, lighting systems, and industrial processes, where interruption could create hazards or hamper rescue or fire-fighting operations. Power must be restored to these loads in not less than 60 s (or less, depending on local codes). Optional standby systems, including heating and refrigeration systems, data processing and communications systems, and industrial processes, where interruption could cause discomfort, serious interruption of the process, damage to the product or process, or the like. Power restoration to these loads should occur, as determined by the engineer, in a period that will adequately protect the loads

TABLE 13.6 Diameters of Circular Ducts in Inches Equivalent to Rectangular Ducts Side 4 8 12 18 24 30 36 42 48 60 72 84 Air filters come in a number of standard sizes and thicknesses. The filter area should be such that the air velocity across the filters does not exceed 350 ft /min for low-velocity filters or 550 ft /min for high-velocity filters. Thus, the minimum filter area in square feet to be provided equals the airflow, ft3 /min, divided by the maximum air velocity across the filters, ft /min. Most air filters are of either the throwaway or cleanable type. Both these types will fit a standard filter rack. Electrostatic filters are usually employed in industrial installations, where a higher percentage of dust removal must be obtained. Check with manufacturers ratings for particle-size removal, capacity, and static-pressure loss; also check electric service required. These units generally are used in combination with regular throwaway or cleanable air filters, which take out the large particles, while the charged electrostatic plates remove the smaller ones. See also Art. 13.6. After air discharge grilles and the air handler, which consists of a heat exchanger and blower, have been located, it is advisable to make a single-line drawing showing the duct layout and the air quantities each branch and line must be able to carry. Of the methods of duct design in use, the equal-friction method is the most practical. It is considered good practice not to exceed a pressure loss of 0.15 in of water per 100 ft of ductwork by friction. Higher friction will result in large power consumption for air circulation. It is also considered good practice to stay below a starting velocity in main ducts of 900 ft /min in residences; 1300 ft /min in schools, theaters, and public buildings; and 1800 ft /min in industrial buildings. Velocity in branch ducts should be about two-thirds of these and in branch risers about onehalf. Too high a velocity will result in noisy and panting ductwork. Too low a velocity will require uneconomical, bulky ducts. TABLE 13.7 Size of Round Ducts for Airflow*