Calculation of humidity parameters and uncertainties using different formulations and softwares

• Autor(a) principal: Orlando, Alcir de Faro
• Data de Publicação: 2004
• Outros Autores: Brionizio, Júlio Dutra, Lima, L. A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional do INMETRO
• Texto Completo: http://hdl.handle.net/10926/766

The increase of importance of humidity instruments in the last 10 years brought their applications to several parts of industry, like automotive, pharmaceutical, food and laboratories to comply with regulations and quality requirements. As consequence, there has been a growing interest of manufacturers and secondary laboratories in having more accurate humidity measurements. That was the moment to consider performance evaluation and calibration issues. A humidity calibration laboratory should pay a special attention to temperature effects on humidity measurements, in order to reduce their uncertainties. Nowadays, there are several commercially available softwares that allow calculation of psychrometer properties, such as vapor pressure (dew point), absolute humidity and relative humidity. These softwares are used by secondary laboratories during their calibrations and can be one of the sources of uncertainty measurements. This paper calculates psychrometer properties for humidity measurements by using the state of the art formulation, and softwares. Then calculates uncertainties for different conditions.