A simple methodology to measure ammonia flux generated in naturally ventilated poultry houses ¤ Una metodología simple para medir el flujo de amoniaco generado en instalaciones avícolas sometidas a ventilación natural Uma metodologia simples para quantificação do fluxo de amônia gerada em aviários submetidos à ventilação natural

Summary Background: quantifying the rate of pollutant emissions, such as ammonia (NH 3 ), from naturally ventilated animal production buildings in structures, such as those used in South America, is challenging mainly due to the challenge of determining building ventilation rate. Some methods have been developed to reduce this difficulty, but most are costly and complex, preventing their implementation. Objective: the present work aimed to adapt and validate the Saraz method for the determination of ammonia emissions (SMDAE) from naturally ventilated poultry houses. Methods: to validate the proposed method, the ammonia emission rate (ER; NH 3 mass emitted per unit time) was computed using the adjusted equation proposed by Wheeler et al. (2006; ER 2 ). For evaluation purposes, the data obtained from the two measuring methods (SMDAE and ER 2 ) were statistically analyzed. Results: the proposed method was considered adequate for use under conditions of natural ventilation with wind speeds greater than 0.1 m/s -1 and NH 3 concentrations greater than 1 ppm. Conclusions: the method demonstrated a good correlation between its values and those obtained by the standard equation for calculating emissions based on NH 3 concentration, air speed and temperature, which makes the Saraz method a reliable approach to develop ammonia inventories for naturally-ventilated poultry facilities.