Toxic gas

“ Naturally, poisonous gases escaping from the furnace such as sulphur dioxide, carbonic oxide, carbon dioxide, and hydrocarbons require to be drawn away and rendered harmless. This can often be done by merely conducting them into the main flue. Gases containing carbonic oxide possess high heating capacity, and their escape can usually be prevented by suitable cupola bells. They can be led away in impervious conduits and utilised for heating purposes or for driving gas [289] engines. Entering the flues for cleaning or repairing purposes is especially dangerous ”

“ All manipulations should take place in tightly closed-in apparatus provided with exhaust, and the gases drawn off should be absorbed or effectively carried away. In the case of many injurious gases it is not sufficient merely to conduct them into the flue; they ought to be condensed and got rid of. Thus acid fumes (nitrous fumes, sulphur dioxide, hydrochloric acid vapour, chlorine gas) are neutralised by water or milk of lime, or a solution of soda; ammonia or alcohol by water; sulphuretted hydrogen and arseniuretted hydrogen by lime and oxide of iron; aniline, &c., by dilute acids. ”

“ But meanwhile the organic portions are undergoing decay, and certain gases are thus evolved, which, mixing together, form what we term “sewer gas.” The principal gases thus given off are carbonic acid, nitrogen, and sulphuretted hydrogen, and although this mixture if breathed is injurious to health, it can not be regarded as poisonous. Thus sulphuretted hydrogen (similar to the odor given off by rotten eggs) although a deadly poison when inhaled in large quantities, is so diluted in sewer gas that its poisonous properties are in a great measure neutralized. ”

“ The iron gas producer, lined with firebrick, is filled with anthracite or coke and heated by blowing hot air through it. This causes producer gas to escape, after which steam is blown through, causing water gas to escape—containing hydrogen and carbonic oxide to the extent of 45-50 per cent., carbon dioxide and nitrogen 2-6 per cent., and a little methane. ”

“ Effects on Health.—Injury to health from work at coke ovens is similar to that in the manufacture of illuminating gas. There is the possibility of carbonic oxide poisoning from escape of gas from leakage in the apparatus. As further possible sources of danger ammonia, cyanogen and sulpho-cyanogen compounds, and benzene have to be borne in mind. ”

“ Those who are constantly engaged in burning the lead sheets and pipes of the chambers suffer not infrequently from severe symptoms. Unfortunately, the work requires skill and experience, and hence alternation of employment is hardly possible.
Finally, mention should be made of poisoning by arseniuretted hydrogen gas from vessels filled with sulphuric acid containing arsenic as an impurity, and by sulphuretted hydrogen gas in purifying the acid itself. In the manufacture of liquid sulphur dioxide, injury to health can arise from inhalation of the acid escaping from the apparatus. ”

“ It owes its dangerous properties to the first-named gas. When water gas, pure and simple, is supplied for heating purposes, its leakage cannot be detected, as the gas possesses no odour. When used for lighting and carburetted, its escape is more readily detected by the smell, but even then it is more dangerous than coal gas as the proportion of CO is higher. Several deaths have resulted from the use of water gas for heating and lighting purposes, and also for steel smelting in Leeds. The symptoms of poisoning are those of carbon monoxide. ”

“ Was there anything in the gas-bomb scare? In the first place, many otherwise well-informed people have very erroneous views as to the poisonousness of gases. Gases are dangerous in the laboratory or factory if they kill without giving warning by odour and irritation; but gases of this kind, such as carbon monoxide and hydrogen arsenide, have to be present, in order to kill, in concentrations which cannot practically be produced in the open. ”

“ Sulphuretted hydrogen and other sulphur compounds are present in small quantities, averaging 12 grains of sulphur per 100 cubic feet of London gas.
The inhalation of coal-gas, even in small quantities, is liable to produce headache, and may lead to chronic poisoning if allowed to continue. Where the escape of gas is more extensive, as when a tap is left turned on accidentally during the night, two dangers may arise. If a light is struck in the room an explosion occurs; or persons may be poisoned in their sleep by inhalation of the gas. ”

“ But even for gas shell bursting some distance away immediate and complete protection is necessary because of the delayed or after effects of the gas, which are exactly similar to those of phosgene. Every care that is taken with regard to men [134] poisoned with phosgene has to be taken for men poisoned with Green Cross gas.
Those suffering from the effects of the gas are not allowed to exert themselves at all or to take heavy meals. They are kept under close observation for at least two days, and are treated, in fact, as casualties even though they are not apparently ill. ”

“ The poisonous properties of coal gas are due to the carbon monoxide, 7.5 per cent. being present in ordinary gas as supplied for illuminating purposes. It can be detected by passing the coal gas through an acid solution of cuprous chloride, which [Pg 401] becomes black by the formation of a compound CuCOCl. A dangerous explosive compound is formed when the gas reaches the proportion of 1 in 10 of the atmosphere. Poisoning by this gas is, as a rule, accidental.
Symptoms.—Headache, nausea, vomiting, giddiness, ending in coma. Stertorous breathing is noticed in some cases. ”

“ Injury to the skin from the acid absorbed in water may occur in filling, unloading, and transport, especially when in carboys, but the burns, if immediately washed, are very slight in comparison with those from sulphuric or nitric acids. Injury to health or inconvenience from sulphuretted hydrogen is at all events possible in the de-arsenicating process by means of sulphuretted hydrogen gas. At the saltcake furnace when worked by hand the fumes containing carbonic oxide gas may be troublesome. In the production of caustic soda severe corrosive action on the skin is frequent. ”

“ Drawing-off these fumes into the furnace (practised sometimes [280] in small industries) is not advisable, as the sulphuretted hydrogen is burnt to sulphur dioxide; if it is burnt absorption of the sulphur dioxide should follow, or working it up into sulphuric acid (Leymann) . Often these gases are freed from cyanogen compounds and sulphuretted hydrogen by means of gas purifying materials, such as are used in gas works. The whole apparatus must be impervious. Where liquids containing ammonia are used exhaust ventilation is necessary. ”

“ In the sulphuring of hops, wine, &c., the workers may run risk from the injurious action of sulphur dioxide. Arsenic in the sulphuric acid used for the production of dextrine may set up industrial poisoning. Poisoning from ammonia gas can occur in cold storage premises. Industrial poisoning from tobacco is not proved, but the injurious effect of the aroma and dust of tobacco—especially in women—in badly arranged tobacco factories is probable. ”

“ Rolling down upon the American and French battlelines, coming out of the German trenches, where it had been generated as soon as it was noted that the wind was right, drifted a cloud of greenish yellow, choking chlorine gas.
Chlorine gas is made by the action of sulphuric acid and manganese dioxide on common salt. It has a peculiar corrosive effect on the nose, throat and lungs, and is most deadly in its effect. It is a heavy gas, and instead of rising, as does hydrogen, one of the lightest of gases, it falls to the ground, thus making it dangerously effective for the Huns. ”

“ Treatment.—Ammonia to the nostrils, inhalation of oxygen, cold douche in moderation, artificial respiration, transfusion of blood.
Coal Gas.—Coal gas contains light carburetted hydrogen or marsh gas, olefiant gas, ammonia, sulphuretted hydrogen, carbonic acid, carbonic oxide, free hydrogen, and nitrogen. Coal gas has an offensive odour, burns with a yellowish-white flame, yielding water and carbonic acid. Cases of poisoning often due to escape of gas into the room. ”

“ Evolution of poisonous gases is greatly increased by the action of moisture, or of moist air, under the influence of which phosphoretted hydrogen is generated from calcium phosphide, which, in turn, is formed, in large part, at any rate, from the calcium phosphate present in anthracite and quartz, at the high temperature of the electric furnace. If spontaneous disintegration of the alloy also occurs, much larger quantities of gas would be given off from such friable and unstable material, other conditions being equal. ”

“ These two gases are mixed in nearly the same proportions in all climates so as to make the beautiful pure air which God has given us to live and go about in. There is another gas, called carbonic acid, made partly of oxygen and partly of carbon, or burnt wood, which might be called "life-destroyer," for it will put out light and make an end of life. It is one of the most deadly poisons, and forms the "choke-damp" which too often suffocates the miner; but what we call fresh air contains such a very small proportion of this dangerous gas that it is harmless. ”

“ Flushing out shall only be done after the workmen have got out.
Workmen are to be warned every time cleaning is undertaken that poisonous gases are developed when the deposit on the floor is diluted.
Acid eggs, further, are to be provided with a waste pipe and manhole to enable cleaning to be done from outside.
The poisoning likely to arise is partly due to arsenic impurity (development of arseniuretted hydrogen gas) in the sulphuric acid used. Unfortunately arsenic free acid is very difficult to obtain. ”

“ Then the cautious inhalation of ammonia, sulphuric ether, or the vapor of warm water, will be useful.
Sulphurous Acid Gas is one of the products formed by the combustion of ordinary coal. It possesses bleaching and antiseptic properties; and is very irritating when inspired.
Nitrous Acid Gas is a very violent poison when inhaled, producing inflammation of the lungs, [Pg 60] &c. It has proved fatal in several instances, when given off by nitric acid.
Hydrochloric Acid Gas is irrespirable in its concentrated state, and when diluted produces great irritation of the lungs and air-passages. ”

“ In mining operations explosives are used on a large scale and the powder gases contain large quantities of the very poisonous gas, carbon monoxide, a small percentage of which may cause death, and even a minute percentage of which in the air will seriously affect the health. In addition to these sources of contamination the air of the mine is frequently charged with gas' issuing from the rocks or from the mineral deposit. For example, carbon dioxide occurs in some mines, and hydrogen sulphide, which is a poisonous gas, in others. ”

“ The addition to it of petroleum-gas as an enricher, for illuminating purposes, at once imparts to it a peculiar odor, as strong as that of coal-gas, which would lead to the immediate detection of a leak." Carbonic oxide is one of the most active poisons, producing, when inhaled, speedy death. Unlike carbonic acid, which, when it poisons, does so by merely preventing the entrance of air or oxygen into the lungs, as water does in case of drowning, so that persons affected can be readily resuscitated, it is a true physiological poison. ”

“ Gas works must be included in this poisonous group, owing to the accidental escape of gas, sometimes in large quantity. In lime kilns enormous volumes of carbonic acid gas are poured out, both from the limestone burnt and from the fuel employed, and in this way persons living in the immediate neighborhood have been suffocated. In chloride of lime (bleaching powder) manufactories, and in places where it is used for bleaching wool and other materials, chlorine gas is given off into the air, causing when inhaled a great amount of irritation in the air passages. ”

“ By a suitable movement of the flask, the acid ferrous chloride is allowed to come in contact with the tissue, a gentle heat applied to the flask, and gases are evolved. These may be carbon dioxide, nitrogen, and nitric oxide. On the evolution of gas ceasing, the carbon dioxide is absorbed by passing up under the mercury a little caustic potash. When absorption is complete, the gas, consisting of nitrogen and nitric oxide, may be measured. A bubble or two of oxygen is now passed into the eudiometer; if nitric oxide is present, red fumes at once develop. ”

“ The relatively high proportion of carbon monoxide in producer-gas is objectionable from a hygienic standpoint, so much so, indeed, that it has attracted the attention of manufacturers. Carbon monoxide, the specific gravity of which is 0.967, is a gas peculiarly poisonous and dangerous. It cannot be breathed without baneful effects, and is even more dangerous than carbonic-acid gas, which eventually causes asphyxiation by reducing the quantity of oxygen in the air. ”

“ These vapours are, in fact, so heavy that they subside almost immediately. When the fulminate mixed with pulverine is exploded in the primers by condensed masses of troops, the mercury will cause no injury to their health, nor one 100th part of the deleterious impression on weak lungs which the gases of exploded gunpowder might by possibility inflict. These gases are all, theoretically speaking, noxious to respiration; such as carbonic acid gas, azote, carburetted hydrogen, and sulphuretted hydrogen, a deadly gas. ”