In this paper a comparison is made of the level of air pollution from two brick production lines that apply different technologies, one old and one new more efficient. The main pollutants emitted into the air from the baking of raw bricks in baking kilns are CO, SO2, NO2, HCl, HF and dust. Monitoring of air pollutants was performed with a Teso 350 flue gas analyzer – the automatic method. A Paul Gothe isokinetic sampler was used to take dust particles, HCl, and HF samples, and the analysis was performed in the laboratory using gravimetry and spectrophotometry as analytical techniques. The results of the tests performed showed a reduction in the level of pollution by applying BAT technologies by up to 90% for all monitored pollutants, compared to the pollution produced by an old, non-retechnologized line. At the same time, energy consumption is lower per unit of product, which results in a significant decrease in production costs.