Floating dynamic chambers were used to measure gaseous emissions from stored pig slurry in 2006. The results show that the chamber method accounted for 4-38 % of the total nitrogen losses and from 61-285 % of the total carbon losses. These results allowed the identification of factors influencing the emissions such as wind speed at the slurry surface and temperature. Basing on these observations, two types of floating dynamic chambers were used to measure gaseous emissions in 2008. The first chamber (C1) had an air speed at the slurry surface of 0.01 m/s and covered a surface of 0.114 m2 (air exchange rate of air = 4E-3 volume s-1), and was automatically placed and removed from the slurry surface each 24 hours. The second chamber (C2) had an air velocity between 0.5 and 0.7 m.s-1 at the surface of the slurry covering 0.34 m2 (renewal rate of air = 35 volume s-1) and was placed in the slurry tank for the duration of the experiment. Each tank contained 11 m3 of slurry. The cylindrical tanks (2.9 m dia.) were placed in real conditions during one month. The concentrations were monitored using an infrared multi-gas monitor (INNOVA 1412). For validation, the results were compared with the nitrogen and carbon input-output mass balances of the slurry. The results show that the gaseous emissions measured with the floating chambers only accounted for 21 and 61 % of the total nitrogen losses, and 86 and 103% of the total carbon losses for C1 and C2, respectively.