Fossil fuel scarcity, global warming and non-constant energy production through renewable energies (wind turbines and photovoltaic cells for example), lead to investigate innovative energy sources and new ways for energy storage. In the present study, magnesium powder has been considered as a new possible energy carrier. In order to analyze more deeply the magnesium combustion and the generated by-products, short time stable magnesium/air flames have been realized in a combustion chamber using an oxy-acetylene flame for ignition. Sieved magnesium samples with two fractions were combusted: 20-50 gm and 50-70 mu m. The power delivered by the Mg/air flame was estimated in the range 3-5 kW. The gaseous emissions (O-2, CO2 from oxy-acetylene combustion, NO and NO2) were analyzed with online analyzers and the particulate emissions were analyzed with an Electrical Low Pressure Impactor (ELPI). The mass concentration of emitted particles whose size is smaller than 10 gm was proved to be very high (up to 35 g/(N)m(3)) and the emitted particles were mainly bigger than 1 gm (84-97 wt%). NOx emissions were higher for the 20-50 mu m Mg fraction (NO average of 4300 +/- 200 mg/(N)m(3)) than for the 50-70 mu m Mg fraction (NO average of 1100 +/- 140 mg/(N)m(3)). (C) 2016 Elsevier Ltd. All rights reserved.