A device used to take odour samples by creating a pressure difference with respect to the inside of the container to the ambient atmosphere. A container that can be sealed (air tight) contains an air pump which can pressurize the container by drawing air from the ambient environment or can create a vacuum by drawing air out of the container into the ambient environment. A bag is placed inside the container which has a different outlet/inlet than the pump. There is no contact or sample with moving parts, such as from a pumps, making it desirable for odour sampling. When the container is under vacuum it draws sample into a bag. When the container is under pressure it draws sample out of the bag (referred to as purging).