Alternatively, a non-combustible air balance duct routed between the cabin and the corridor and located below the sanitary unit is permitted where the cross-sectional area of the duct does not exceed 0,05 m2.
Alternativno pa se dovoli negorljiv vod za izravnavanje zraka, ki poteka med kabino in hodnikom ter je nameščen pod sanitarnimi prostori, če premer vodov ne presega 0,05 m2.