Document 5bjVXobLJGExKO5VqNQMEkzKJ

198 CHAPTER 10 . 1946 Guide BffiUQGRAPHY , Abstracts and Bulletins (monthly, annual and special) Industrial Hygiene Founda tion, Inc., Pittsburgh, Pa. Aerobiology, Publication No. 17 {American Association for the Advancement of Sci ence, Washington, D! C., 1942). . Air Sanitation and Industrial Ventilation, by W. N. Witheridge (Detroit Department of Health, 1945). Analytical Chemistry of Industrial Poisons, Hazards and Solvents, by M. B. Jacobs (Interscience Publishers, New York, 1941). Bibliography of Industrial Hygiene, 1900-1943 (U. 5. Public Health Service Bul letin No. 289, 1945). Clouds and Smokes, by W. E. Gibbs (P. Blakiston's Son & Co., Philadelphia, Pa., 1924). Determination and Control of Industrial Dust, by Bloomfield and DallaValle (U. S. Public Health Service Bulletin No. 217, 1935). . Dust, by S. C. Blacktin (The Sherwood Press, Cleveland, 1934). ; .(The) Environment and Its Effect upon Man (Harvard School of Public Health, Boston, 1937). ' Health Practices Pamphlets;' Industrial Data Sheets {National Safety Council, Chicago): . Industrial Dust, by Drinker and Hatch (McGraw Hill Book Co., New York, 1936). - Industrial Hygiene Bulletin (monthly) (New York State Department of Labor). Industrial Medicine (monthly) (Industrial Medicine Publishing Co., Chicago, 111.). Journal of Industrial Hygiene and Toxicology (monthly) (Harvard School of Public Health, Boston, Mass.): See cumulative abstract and subject indexes. Manual of Industrial Hygiene, by W. M. Gafafer et al (U.S. Public.Health Service, W. B. Saunders Co., Philadelphia, 1943). Noxious Gases and the Principles of Respiration Influencing their Action, by Hender son and Haggard {American Chemical Society Monograph Sertes No. 35, Reinhold, New York, 1943). . Occupation and Health, two volumes {International Labor Office, Washington, D. C.). Occupation Hazards and Diagnostic Signs, by Dublin and Vane (17. S. Dept, of Labor, Division of Labor Standards Bulletin No. 41, 1942). Toxicology and Hygiene of Industrial Solvents, by Lehmann and Flury, translated by Eleanor King and H. F. Smyth, Jr. (Williams and Wilkins, Baltimore, 1943). War Gases, by M. B. Jacobs (Interscience Publishers, New York, 1942). Yearbooks {American Public Health Association). CHAPTER 1 1 trumenti and *ffl\ea&urement& Temperature Measurement, Pressure Measurement, Measurement of Air Movement, Air Change Measurements, Measurement of Relative Humidity, Dust Determination, Heat Transfer Through Building Materials, Measurement of Heat Exchange for Comfort Conditions, Combustion Analysis, Smoke Density Measurements THIS chapter presents a description of many test instruments used for heating, ventilating and air conditioning tests and presents a discussion of their use. TEMPERATURE MEASUREMENT Changes in the intensity of heat may be determined by several methods1 such as measuring the change in volume of a liquid, the change in internal pressure of a confined gas, the current set up between dissimilar metals joined in a circuit, or the change in resistance of an electrical circuit. Thermometers The most common method used is the change in volume of a liquid such as mercury or alcohol enclosed in glass. Mercurial thermometers may be used for measuring temperatures from -- 40 F to approximately 1000 F. The lower limit is set by the freezing point of mercury. Since the boiling point of mercury is only about 675 F, the space above the mercury in thermometers designed for higher temperatures must be filled with an inert gas under pressure. Alcohol thermometers may be used for temperatures from -- 94 F to +248 F. The more accurate thermometers have divisions etched on the stem and are preferred for test purposes due to their low heat capacity.. During their manufacture, the freezing aiid boiling points of water are first marked while the thermometer is immersed in a test bath. The required divisions between these points, whether Centigrade or Fahrenheit, are then marked and etched' on the stem. In spite of these precautions the probable error in etched stem thermometers is,'plus'or minus one scale division, which makes calibration after manufacture necessary for most test work. Such thermometers are usually calibrated for complete stem immersion. When incompletely immersed, a stem .correction should be made. At ordinary atmospheric temperatures the correction is negligibly.small,, but it usually is important when measuring high temperatures such as those of steam and flue gas. The emergent stem, correction may be calculated by the equation: i K = 0.00009 D{h -t,) (1). where K = correction to be added, Fahrenheit degrees. '1 d =: number of degrees on the thermometer scale which are not immersed, u = temperature indicated on the thermometer, Fahrenheit degrees, u.=. temperature of the non-immersed mercury column, Fahrenheit degrees, 0.00009 = difference in the coefficient-of expansion of the mercury.and glass. ' 1 . 199 '