If, notwithstanding this, severe symptoms develop, oxygen inhalation should be commenced forthwith and medical aid called in. Production of Vegetable Foods and Luxuries (See also p. 154) Measures for the prevention of industrial poisoning have to be thought of in connection with drying processes (by smoke gases, carbon dioxide, and carbonic oxide), many processes of preserving (use of sulphur dioxide, &c.), and fermentation (accumulation of carbonic acid). In breweries the use of kilns allowing fire gases to enter the drying-rooms formerly caused carbonic oxide and carbonic acid poisoning. The general introduction of hot air kilns provided with mechanical malt-turning apparatus should be insisted on, and is in keeping with progress in technical methods. The accumulation of carbonic acid in the malting cellars can be prevented in the same way as in a distillery. If ammonia is used for _refrigeration_, precautions are necessary so that, in the event of leakage or bursting of pipes, the workers may escape. Naturally the imperviousness of the freezing system must be guaranteed. Oppression and danger to the health of the workers is occasionally caused by the development of gases in the coating of barrels with pitch, partly preventable by the use of pitching machines. In the production of _spirits_ carbonic acid poisoning can occur from accumulation of carbonic acid in the fermentation cellars. These should be thoroughly ventilated and in view of the heaviness of the gas, openings for ventilation should always be located at the floor level. In the _sulphuring of malt_ the following recommendations were made by the Austrian inspectors: During the sulphuring process the room ought not to be entered (for the turning over of the malt). When the sulphur has been burnt, the drying-room must be ventilated from the outside, by opening the windows and letting in cold currents of air, until the sulphur dioxide has completely dispersed, which can be tested by holding a strip of moistened blue litmus paper at the half-opened door. If it does not turn red, turning over of the malt may be proceeded with. As the _sulphuring of hops_ in hop districts is done in primitive little kilns, in which the hops are spread out on a kind of gridiron and sulphur burnt below in iron pans, development of sulphur dioxide may affect the workers. The following regulations are therefore suggested for work in these kilns: The rooms in which sulphuring takes place must be airtight, capable of being locked, and provided with arrangements which make it possible to remove the sulphur dioxide fumes before the room is entered. This can usually be done by a strong coke fire, maintained in the chimney place, which creates the necessary draught. If fans are used, it must be remembered that iron is affected and destroyed by acid gases; stoneware fans are therefore advisable.