Chapter XVIII: Section 120: of the Factory Code; (2) report by the Imperial Health Office (2)

III. Provides for the method of permitting the exceptions
named above in sections 2 and 3, and makes it a condition of
reduction in cubic air space for each person employed as type
founder or compositor that there shall be adequate mechanical
ventilation for regulating temperature and carrying off
products of combustion from workrooms.

Ceramic Industry

(See also pp. 135-8.)

A complete substitute for lead in glazes seems as yet impossible on technical grounds, as glaze containing lead has qualities which cannot be obtained without its use. In small works the technique necessary for the production of leadless glazes (special kinds of stoves) cannot be expected, especially as those carrying on a small industry lack the necessary knowledge of how to be able to dispense with the use of lead glazes and substitute leadless materials without complete alteration in their methods of manufacture. And yet discontinuance or the utmost possible limitation of the use of lead glazes and colours is most urgently needed in all small ceramic workshops, as they are not in a position to put in localised exhaust ventilation, &c., which is possible in large factories. Observance of even the simplest hygienic measures can scarcely be obtained. Consequently very severe cases of lead poisoning are met with in small works. An effort in the direction of discontinuance of lead glazes was made in Bohemia, where (at the cost of the State) technical instruction was given by an expert on the preparation of leadless glazes especially in districts where the industry was carried on in the homes of the workers. This procedure, extension of which is expected, had good results.

Many have demanded, in view of the possibility of substituting leadless for lead glazes, the total prohibition of lead. Such is the view of the Dutch inspector De Vooys; Teleky and Chyzer share the view expressed so far as the small industry is concerned, since the practicability of the change has been demonstrated.

English authorities (Thorpe, Oliver) propose diminution of the lead in the glaze in such a way that on shaking with weak acid not more than a specified small quantity shall be dissolved (Thorpe test). In my opinion such a measure is hardly enough for the small industry. I do not expect much good from obligatory use of fritted glazes.

In addition to earthenware, manufacture of tiles and bricks leads not infrequently to cases of lead poisoning from use of lead glaze.

The following measures apply to the larger ceramic works. Since risk is considerable, not only in glost placing but also in grinding, ware-cleaning, &c., closed ball mills in grinding and locally applied exhaust ventilation in ware-cleaning operations, &c., must be arranged. Personal cleanliness and proper equipment of a factory in all the essentials insisted on on pp. 226-9 are important, but nothing can take the place of efficient locally applied ventilation.

Vitreous enamelling of household utensils, baths, gas stoves, signs, &c., is an analogous process as enamels containing lead may be used. Sieving on the dry powder and brushing off superfluous glaze often cause poisoning. Here generally the same preventive measures apply.

[In Great Britain the china and earthenware industry is placed under Regulations dated January 2, 1913, which supersede the previous Special Rules. These Regulations—thirty-six in number—provide, among other usual provisions, (1) for efficient exhaust ventilation in (_a_) processes giving rise to injurious mineral dust (fettling and pressing of tiles, bedding, and flinting, brushing and scouring of biscuit) and (_b_) dusty lead processes (ware cleaning, aerographing, colour dusting, litho-transfer making, &c.); and (2) monthly periodical medical examination of workers in scheduled lead processes.]

In the Netherlands, in consequence of lead poisoning in porcelain works, committees were appointed to inquire into the subject in 1901, 1902, and 1903.

File Cutting

(See also p. 140)

In file cutting the file is cut on a lead bed or a bed of an alloy of zinc and lead. The same source of poisoning occurs in other industries such as amber working. Lead poisoning among file cutters is pronounced. The best preventive measure is substitution of a bed of pure zinc for lead. The German Imperial Health Office have issued a ‘Warning notice’ for file-cutters.

LEAFLET FOR FILE-CUTTERS

The use of lead beds or of alloys of lead with other metals
has repeatedly brought about lead poisoning in file-cutters.
The beds also supposed to be made of zinc usually contain a
considerable proportion of lead, and are thus dangerous to
health.

Among file-cutters lead poisoning arises from absorption of
the metal in small quantities by means of dirty hands, eating,
drinking, smoking or chewing of tobacco. The consequences of
this absorption are not at once noticeable. They appear only
after weeks, months, or even years, according to the extent to
which the lead has accumulated in the system.

_How does lead poisoning show itself?_—The first sign is
usually a bluish-grey line on the gums called the blue line,
associated with anæmia or pallor. Later symptoms are very
varied. Most frequently lead colic comes on, the affected
person suffering from violent cramplike pains starting from the
navel; the stomach is hard and contracted; very often vomiting
and constipation ensue, or, very occasionally, diarrhœa. In
some cases paralysis shows itself—generally in those muscles
which extend the fingers, usually affecting both arms. In
exceptional cases other muscles of the arms and legs are
affected. Sometimes lead poisoning manifests itself in violent
pains in the joints—generally the knee, more rarely in the
shoulder and elbow. In specially severe cases brain trouble
supervenes—violent headache, convulsions, unconsciousness or
blindness. Finally lead poisoning may set up disease of the
kidneys—Bright’s disease and gout.

Women suffering from lead poisoning frequently miscarry.
Children born alive may, in consequence of lead poisoning, die
in their first year. Children fed at the breast are poisoned
through the milk.

Apart from severe cases complicated with brain trouble,
which are often fatal, persons suffering from lead poisoning
generally recover if they withdraw from further contact.
Recovery takes place after a few weeks, but in severe cases
only after months.

The most effective preventive measures are cleanliness
and temperance. Persons who, without being drunkards, are
accustomed to take spirits in quantity are more likely to
succumb than the abstemious. Spirits should not be taken
during working hours. In regard to cleanliness, file-cutters
using lead beds should be especially careful and observe the
following rules:

1. Since soiling the hands with lead cannot be entirely
avoided, smoking and chewing tobacco during work should be
given up.

2. Workers should only take food and drink or leave the works
after thoroughly washing the hands with soap—if possible with
pumice stone; if drinking during work cannot be wholly given up
the edges of the drinking vessels ought not to be touched by
the hands.

If a file-cutter falls ill in spite of precautions with
symptoms pointing to lead poisoning he should, in his own and
his family’s interest, at once consult a doctor, telling him
that he has been working with a lead bed.

Other Industries in which Lead is used

In cutting _precious stones_ with use of lead discs lead poisoning frequently occurs, especially where this trade, as in some parts of Bohemia, is carried on as a home industry. The authorities have required substitution of carborundum (silicon carbide) for lead discs. As, therefore, an efficient substitute is possible, use of lead should be prohibited. Similarly, use of lead in the making of musical instruments should, if possible, be discontinued. Brass pipes in _musical instrument_ making are filled with lead to facilitate hammering and bending, and in this way poisoning has occurred. In numerous other industries where the use of lead cannot be avoided, and where consequently the danger must be present, as, for instance, in _lead melting_, _soldering_, _lead rolling_, _stamping_, _pressing_, &c., in the manufacture of _lead piping_, _shot_, _wire_, _bottle capsules_, _foil_, _toys_, and many other articles, general preventive measures should be carefully carried out. _Melting of lead_ and _lead alloys_ should be carried out only under efficient exhaust ventilation. In larger works where dust is generated this should be drawn away at the point where it is produced. This applies also to processes in the chemical industries where lead or lead compounds are used, seeing that no substitute is possible.

Zinc, Brass-casting, Metal Pickling, Galvanising

(See also pp. 151 and 182)

In zinc smelting account has to be taken of fumes which may contain lead, zinc, arsenic, sulphur dioxide, and carbonic oxide. Metallic fumes require to be condensed—a procedure in harmony with economic interests. This is effected in a technically arranged condensing system, consisting of a condenser and prolong, in which the fumes are given as large a space as possible in which to condense and cool. In order to prevent the entry of fumes into the shed when removing distillation residues, hoods should be arranged over the front of the furnace through which the gases can be conducted into the main chimney stack or be drawn away by a fan; in addition the residue should fall into trolleys which must either be covered at once or placed under a closely fitting hood until the fuming contents are cool. As the mixing of the materials for charging and the sifting and packing of the zinc dust (poussière) may cause risk, these processes require to be carried out mechanically with application of local exhaust. Such an arrangement is shown in fig. 59 below. The material which is fed in is carried by the elevator to the sifting machine, falls into the collecting bin, and is then packed. The points at which dust can come off are connected with the exhaust and carried to the dust collector; fans carry the filtered air to the outside atmosphere.

_a_ Charging hopper; _b_ Distributor; _c_ Elevator; _d_ Sieve; _e_ Collector; _f_ Packing machine; _g_ Exhaust pipe; _h_ Worm; _i_ Dust Collector; _k_ Motor]

Only paragraphs 3-8 of the German Imperial Regulations dated February 6, 1900, for Spelter Works are quoted, as the remainder are on precisely similar lines to those for lead smelting works given in full on p. 300.

3. Crushing zinc ore shall not be done except in an apparatus
so arranged as to prevent penetration of dust into the workroom.

4. The roasting furnaces as well as the calcining furnaces
shall be provided with effective exhaust arrangements for the
escaping gases. The occupier shall be responsible for their
efficiency during the time the furnace is at work.

5. To avoid dust, ores intended for charging distillation
furnaces shall not be stacked in front of or charged into
the furnace, or mixed with other material, except in a damp
condition.

This regulation shall not apply to large so-called Silesian

Retorts when in use in the zinc smelter; yet in the case of
them also the Higher Authorities may require damping of the
charging material if specially injurious to health.

6. Dust, gases and vapours escaping from distillation furnaces
shall be caught as near as possible to the point of origin by
efficient arrangements and carried out of the smelting rooms.
The entrance of the gases from the fires into the smelting room
shall be prevented as far as possible by suitable arrangements
for drawing them off.

7. Residues shall not be drawn into the smelting room; they
shall be caught in closed channels under the furnaces and
emptied from these channels at once into waggons placed in
passages beneath the distillation rooms.

This regulation (where the Higher Authorities approve) shall
not apply to existing plants, should it be impossible to make
the arrangements mentioned in Reg. 1, or where such additions
could only be added by rebuilding at a prohibitive cost.

8. Sieving and packing of by-products obtained by the
distillation of zinc (poussière, flue dust) shall not be done
except in a special room separate from other workrooms, in
accordance with Reg. 1.

Sieving shall only be done in an apparatus so arranged as to
prevent escape of dust.

In _brass casting_, in order to prevent occurrence of brass-founders’ ague, it is necessary that the zinc oxide fumes evolved should be effectively drawn away from the crucible by locally applied exhaust ventilation. General ventilation merely of the room is almost useless, as in casting the fumes rise up into the face of the pourer. Seeing that casting is carried on in different parts of the foundry, it is advisable to connect up the hoods over the moulds by means of metal piping with the exhaust system, or to arrange a flexible duct which can be moved about as occasion requires.

Dangerous acid fumes (notably nitrous fumes) are evolved in metal pickling, especially of brass articles (such as harness furniture, lamp fittings, church utensils, &c.), for the purpose of giving them a shiny or dull surface by immersion in baths of nitric, hydrochloric, or sulphuric acid. As severe and even fatal poisoning has occurred in these operations they should be conducted in isolated compartments or channels under exhaust ventilation. If the ventilation provided is mechanical an acid proof earthenware fan or an injector is necessary. The following description applies to one large works: The pickling troughs are placed in a wooden compartment closed in except for a small opening in front. To this compartment a stoneware pipe leading to a stoneware fan is connected. The nitrous fumes are drawn through the pipe and led into the lower part of an absorption tower filled with cone-shaped packing material through which water trickles from a vessel placed at the top. The greater part of the acid fumes are absorbed as they pass upwards and the water collects in a receiver below, from which it is blown by compressed air into the vessel above for utilisation again until it becomes so charged with acid that it can be used for pickling purposes.

In _galvanising_ and _tinning_ acid fumes, injurious acroleic vapour, and metallic fumes can arise as the metal articles (iron, copper, &c.) first require to be cleaned in an acid bath and then dipped into molten fat or molten zinc or tin. Here also the fumes should be drawn away in the manner described.

Recovery and Use of Mercury

Escape of mercury vapour and development of sulphur dioxide seriously endanger workers engaged in smelting cinnabar. The danger can be minimised by proper construction of furnaces preventing escape as far as possible of fumes and most careful condensation of the mercury in impervious and sufficiently capacious chambers and flues.

Continuous furnaces are to be preferred to those working intermittently. The system of condensing chambers and flues must offer as long a passage as possible to the fumes, and care must be taken to keep them thoroughly cool. Removal of the deposit rich in mercury from the flues is especially fraught with danger. This work should only be carried on after efficient watering by workers equipped with respirators, working suits, &c.

_Use of mercury._—Mirror making by coating the glass with mercury used to be one of the most dangerous occupations. Now that a fully adequate substitute for mercury has been found in the nitrate of silver and ammonia process, use of mercury should be prohibited. As a home industry especially mirror coating with mercury should be suppressed. Fortunately the dangerous mode of production is rapidly being ousted.

The following requirements are contained in a decree of the Prussian Government dated May 18, 1889:

(1) Medical certificate on admission to employment in mirror making with use of mercury;

(2) restriction of hours to six in summer and in winter to eight daily, with a two hours’ mid-day interval;

(3) fortnightly examination of the workers;

(4) air space per person of 40 cubic meters in the coating room and 30 in the drying room, and, in both, introduction of 60 cubic meters of air per head per hour;

(5) Work to cease if the temperature of the room in summer reaches 25° C.

Measures are necessary to prevent occurrence of mercury poisoning in hatters’ furriers’ processes (preparation of rabbit fur for felt hats) in consequence of the use of nitrate of mercury. Danger arises chiefly in cutting the hair, in dressing and drying, in sorting, and also in the subsequent stages of hard felt hat manufacture. Aspiration of the dust and fluff at its point of generation, isolation of the drying rooms and prohibition of entry into them while drying is going on, are necessary. In dressing (commonly known as ‘carotting’), the nitric acid vapour requires to be drawn away. In addition strict personal hygiene, especially of the teeth, is very important. Processes involving _water gilding_ (nowadays practised on a very small scale) should only be carried on in stoves provided with exhaust ventilation. Electroplating, fortunately, has almost entirely taken its place.

As cases of mercury poisoning have been reported from use of mercurial pumps in producing the vacuum inside _electric incandescent bulbs_, air pumps should be substituted for them whenever possible.

_Barometer_ and _thermometer_ makers may and do suffer severely if care is not taken to draw away the fumes and ensure good ventilation of the workrooms. Careless handling and the dropping of mercury on the benches make it difficult to prevent some volatilisation. Personal hygiene and especially a proper hygiene of the mouth are of the greatest importance in this class of work.

Preparation of mercury compounds in chemical factories, especially the dry processes (sublimation), as in production of cinnabar, corrosive sublimate and calomel mixing, grinding, and sublimation, require to be carried on in closed apparatus. Preparation of the substances named above in solution involves much less risk than subliming. From our point of view, therefore, the former is to preferred.

Arsenic, Arsenic Compounds, Arseniuretted Hydrogen

For arsenic works imperviousness of the system and as complete condensation as possible are necessary to prevent escape of fumes.

Respirators should be worn in manipulations with white arsenic, and such work as packing done under conditions of locally applied exhaust ventilation.

Industrial use of arsenic compounds, in view of the risk attaching to them, should be reduced as much as possible. This has sometimes been achieved by technical improvement in processes of manufacture. Thus in the colour industry, where formerly colours containing arsenic played an important rôle, coal-tar colours have taken their place, and use of arsenic even in these (as in the manufacture of fuchsin) has been replaced by nitrobenzene.

As the danger from arseniuretted hydrogen gas is especially great in processes in which acid acts on metal and either one or both of them contain arsenic, the materials, should be as free from arsenic as possible, in the production, for example, of hydrogen for soldering, in extracting metals by means of acids, in galvanic elements, in accumulator works, in the storage and transport of acids in metal vessels, and in galvanising.

In any case the workers in these industries should be warned of the danger and instructed in case of emergencies. For soldering exclusive use of hydrogen produced electrolytically and procurable in steel cylinders is advisable.

Extraction and Use of Gold and Silver

In the extraction of gold and silver by amalgamation and subsequent volatilisation of mercury there is risk of mercurial poisoning. The preventive measures necessary are similar to those for poisoning in the recovery of mercury (see p. 327).

_Argyria_ in pearl bead blowers can be avoided by using pumps to blow the silver solution into the beads instead of the mouth.

In electroplating the possibility of poisonous fumes arising from the baths must be guarded against because hydrocyanic (prussic) acid, though only in minute quantities, may be evolved; care must be taken that the workrooms are well ventilated or the baths hooded. Careful personal hygiene is essential, for the prevention of skin diseases from which workers in electroplating often suffer.

VII

_PREVENTIVE MEASURES IN OTHER TRADES_

Ceramic Industry

In the glass industry use of lead, chrome, and arsenic compounds should be restricted as much as possible or allowed only under suitable precautions (exhaust ventilation, personal hygiene, &c.).

_Etching on glass_ by means of hydrofluoric causes almost inevitably injury to the workers. Rendering the surface of glass opaque should preferably be done by sand blast. When a bath of hydrofluoric acid for etching on glass is used the fumes require to be drawn away by hoods over the baths and the work-rooms well ventilated.

Further precautionary measures are called for in view of industrial poisoning by furnace gases in various ceramic industries, as, for example, cement works, glass works, and tile works.

The following suggestions are made in the technical introduction to the Germany Factory Act for prevention of poisoning from carbonic oxide, carbon dioxide, and sulphur dioxide:

(1) Even the fixing of benches which might be used for sleeping on near the furnaces should be strictly forbidden;

(2) All furnaces which are roofed over should be provided with adequate side and roof ventilation;

(3) All gas pipes and cocks must be maintained in an impervious condition.

Manufacture and Use of Varnishes and Drying Oils

Unpleasant fumes are given off on boiling linseed oil with oxidising substances, which should be prevented by closely fitting covers and condensation of the fumes in cooling apparatus. In heating and dissolving resin for the production of varnishes the fumes evolved require to be dealt with in a similar way.

Preventive measures must be taken also in the use of quick-drying paints on ships and inside steam boilers as, owing to the rapid evaporation of the poisonous solvents—benzene, benzine and turpentine—fatalities have occurred. As a result of elaborate investigation by the inspectors of factories in Hamburg the following instructions were issued:

Quick-drying paint for ships and for preventing rust should
only be used under the supervision of a person conversant with
the danger to health and risk from fire.

They should only be allowed for the painting of interior
surfaces after adoption of adequate precautions—free
ventilation, use of smoke helmets with air conducting
apparatus, and no naked lights, &c. Since use of quick-drying
paints cannot easily be prohibited and the fumes from the
substitutes for turpentine—benzene and other light tarry
oils—exert injurious effect on man, precautionary measures are
called for. Regulation of working hours is as important as
provision of adequate ventilation. Workers, therefore, should
be allowed proper intervals from work.

Confined spaces in the interior of ships should be adequately
ventilated before, after, and during work; all persons who use
the paints should have opportunity for washing given them at
their work places, and should be compelled to avail themselves
of these facilities; indulgence in alcohol and smoking should
be prohibited; receptacles in which quick-drying paints are
sold should be provided with an air-tight cover and with a
warning notice as to the danger of the contents.

Paints made from petroleum fractions of low boiling-point,
light coal-tar oils, turpentine oil, carbon bisulphide, and
similar substances, are to be regarded as injurious to health.

Persons under eighteen, and women, should not be allowed to
work with quick-drying paints.

Obligatory notification of cases of poisoning by hydrocarbons
and other similar poisonings would have a good effect.

Schaefer (Inspector of Factories in Hamburg) has drawn up the following leaflet for painters, varnishers, workers in dry docks, and others engaged in painting with quick drying paints and oils:

All quick-drying paints and oils are more or less injurious
to health and very inflammable, as they contain volatile
substances such as benzine (naphtha, petrol ether), benzene,
turpentine oil, carbon bisulphide, &c. These paints are mostly
used in painting interiors of ships, boilers, machinery,
apparatus, &c., and come on the market under various
names, such as Black Varnish Oil, Solution, Patent Colour,
Anti-corrosive, Dermatin, Acid-proof Paint, Apexior, Saxol, &c.

Even at ordinary temperatures the volatile fluids used
as mediums for dry paint powders, or as a first coating,
evaporate. Air filled with the fumes is not only harmful to
health, but liable to explosion. Working with these paints and
oils in the interior of ships, or steam boilers and the like,
has repeatedly led to explosions and fatal poisoning.

_Danger of Poisoning._—All persons are exposed to the danger of
poisoning who use quick-drying paints in the interior of rooms
or receptacles, or otherwise manipulate the paints. The warmer
the room and the less ventilation there is before and during
the painting, the greater the danger of poisoning. On the other
hand, use of these paints in the open air is generally without
effect.

Poisoning arises from inhaling the fumes of hydrocarbons.
The symptoms are oppression, headache, inclination to vomit,
cough, hiccough, giddiness, noises in the ears, drunken-like
excitement, trembling and twitching. Inhalation of larger
quantities brings on, quite suddenly and without previous
warning, unconsciousness, which may last many hours and is
often fatal. Except in severe cases the symptoms generally
soon disappear, if the affected person withdraws from further
contact with the fumes. The most effective protection therefore
against poisoning is fresh air and temperance. In so far as
painting with quick-drying materials is necessary in workrooms,
interiors of ships, water and ballast tanks, double bottoms,
bunkers, bilges, cabins, boilers and receptacles, care must
be taken to ensure thorough ventilation before, after, and
while the work is going on. Where no sufficient ventilation
is possible these paints ought not to be used. Frequent
intermission of work by a short stay in the open air is useful.
When working in spaces not easily accessible, the worker should
be roped.

Speaking, singing, or whistling during work favours inhalation
of the fumes and is, therefore, to be avoided. Indulgence in
spirits, especially during working hours, increases the danger
of poisoning. Habitual drinkers should not be allowed to work
at all with quick-drying paints and oils.

At the first signs of discomfort work should be stopped. An
immediate stay in the open air will then usually dispel the
poisonous symptoms.

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.

In the production of _vinegar_, air escapes laden with acetic acid vapour, alcohol, lower oxidation products of alcohol, aldehyde, acetic ether, &c. Their escape can be avoided if the whole process is carried on in a closed self-acting apparatus with the advantage also that no loss occurs.

In premises for _drying agricultural products_ (fruit, chicory, turnips) the persons employed in the drying-room are exposed to the danger of carbonic oxide poisoning from direct firing.

The following recommendations for work in drying-rooms with direct firing are taken from an Austrian decree of 1901:

The lower drying chambers, in which the real drying process
is effected, should be so arranged that the objects dried in
them can be removed by means of long-handled implements through
a passage shut off from the drying-room. The separation of
this passage can be effected by loose tin plates which can be
removed as required for the work of turning or removal of the
dried products, so that the worker need not come into contact
with the gases.

Open fires should be so arranged that if required they can
be shut off, by simple arrangements, from the drying-rooms
in which the workers are temporarily occupied in carrying
in, and turning, the objects to be dried, transferring the
partly dried products to hotter hurdles, and emptying them
when finished, in such a way that the entrance of combustion
gases into the drying chambers can be completely prevented. In
order, however, to prevent a back draught, arrangements must be
made for simultaneous removal of the gases by pipes connected
with a chimney or smoke flue. The places from which the fires
are charged should, in addition, be furnished with suitably
arranged openings for ventilation leading into the outer air,
in order to neutralise, in case of need, any back draught from
the furnaces into the rooms.

The windows of the drying chambers should be so arranged as to
open both from within and without.

The floor of the roof space, or attic, which forms at the same
time the ceiling of the upper drying-room, should be kept
perfectly airtight, as also the openings into it through which
the steam pipes pass. For this purpose the floor should be a
double one and the openings or boxes into which material is
thrown should have a double cover above and below. Further,
situated in the highest point of the ceiling of the roof space,
there should be a suitable number of openings topped by louvred
turrets. In the roof space no work should be done except
manipulations necessary for the charging of the hurdles with
the goods to be dried. Use of the roof floor as a sleeping or
living room is not permissible.

Before the workers enter the drying chambers for the purpose of
turning the materials, the stove should be shut off, the gases
drawn from the furnace into the chimney or flue, and at the
same time the doors and windows of the drying rooms opened.

Entering of drying chambers for working purposes should only be
done after a sufficient time has elapsed for removal of the air
by ventilation.

Charging of the furnaces should be so arranged that they burn
as low as possible before the removal of the dried materials
and before subsequent work in the drying chambers. Seeing that
chicory and turnip drying is done intermittently by night, a
special sleeping or waiting room with free ventilation should
be provided. The regulations concerning the ventilation of the
workrooms are to be made known to the workers.

Cigar Industry

In order to prevent injury to health to tobacco workers the dust and fumes, especially at cutting and sifting machines, require to be drawn away by locally applied exhaust ventilation. The workrooms, moreover, must conform to hygienic requirements, especially as to cleanliness. Washing accommodation and baths are desirable, but are only likely to be provided in large works.

Wood Working

(See also p. 154)

Risk from poisonous woods can be avoided by exhaust ventilation applied to the wood-working machinery.

To lessen the danger to health in the use of methylated spirits in the polishing of wood adequate ventilation of the workrooms is necessary; drawing off the fumes by local ventilation is often impossible.

Production of Wood-pulp (Cellulose) and Paper.

In the _sulphite cellulose_ process, sulphur dioxide may escape from the sulphur stoves or from the boilers; escape of sulphur dioxide is also possible through defective gas pipes and condensers. Gas pipes and condensers require to be quite impervious and condensation or absorption as complete as possible. The fumes escaping from the boilers should be led through pipes into closed boilers for condensation purposes; the gases not condensed here are to be led into absorption towers.

In the manufacture of _paper_ with use of chloride of lime for bleaching chlorine can be given off in considerable quantity, requiring removal of the gases from the apparatus.

The use of poisonous colours containing lead or arsenic, and addition of lead-containing substances to the paper pulp, is now very rare.

Textile Industries.

(See also p. 156)

In the textile industry only a few manipulations are associated with serious risk of poisoning. Those engaged in carbonising are exposed to acid fumes; closed and ventilated apparatus, therefore, as far as possible, require to be used and the acid gases escaping from them should be absorbed. These requirements are fulfilled by carbonising stoves which are ventilated and connected with coke condensers. It is especially urged that only arsenic free acid be employed, as otherwise danger of poisoning by arseniuretted hydrogen may be incurred.

In the making of _artificial silk_, according to the Chardonnet-Cadoret process, the precautionary measures recommended in nitrating together with careful exhaustion of the ether and camphor fumes apply.

The combustion gases (containing carbonic oxide) developed in the process of singeing are harmful and require to be led away at their source.

Poisonous metallic salts, especially lead and lead-containing zinc, are used as weighting materials, in dressing or finishing, and sometimes cause symptoms among the workers. Apart from the danger to those occupied in spinning and weaving, the workers who handle these products (in the clothing trade) also run a risk from lead.

Precautionary measures are necessary in the _varnishing of woven materials_, as the substances employed may contain volatile poisonous solvents. If these poisonous solvents cannot be replaced by others less poisonous, carefully applied exhaust ventilation must be provided. The same holds good when carbon bisulphide, benzene, and benzine are used as solvents in the production of woven materials impregnated with indiarubber.

Employment of lead salts and other poisonous metallic salts in the glossing of woven materials, or in order to render them non-inflammable, is to be deprecated.

Cases of lead poisoning have occurred in the working-up of asbestos, as lead wire is sometimes used in the process of weaving.

To protect workers in _chlorine_ and _sulphur bleaching_ from poisoning by chlorine or sulphur dioxide the gases arising from the bleaching liquids should be drawn away. Use of closed bleaching apparatus, as is the case in large works, reduces the danger to a minimum. Bleaching-rooms should be connected with a powerful stoneware fan, so that they may be thoroughly aired before they are entered.

Dye Works

Industrial poisoning by dyes is, in general, rare, as the natural dyes (wood and tar dyes) are almost without exception non-poisonous. Further, the dyes are generally only used in diluted solution. Formerly the arsenic in many tar dyes caused poisoning, but now it is usually the mordants which have harmful effect. To this class belong chromic acid salts and mordants containing arsenic, antimony (tartar-emetic), and also chloride of tin. In the scraping off of layers of paint containing arsenic, arsenic dust may arise. In Turkey red dyeworks, especially sodium arsenite is used for fixing the tar dyes.

Orpiment dyes which may give off poisonous arseniuretted hydrogen gas are becoming less and less used; from the point of view of industrial hygiene, the utmost possible avoidance of the use of arsenic-containing preparations in dye works is to be recommended. Where this is not possible, strict personal hygiene must be enforced (as, for instance, application of vaseline to the skin).

FOOTNOTES

[A] Leymann has dealt with the conditions of health in a large aniline factory in a later work which is referred to in detail in the section on the aniline industry.

[B] Poisoning by lead, phosphorus, and arsenic contracted in a factory or Workshop has been notifiable in Great Britain and Ireland since 1895.

[C] ‘On the Nature, Uses, and Manufacture of Ferro-silicon,’ 1909, Cd. 4958.

[D] In Great Britain section 73 of the Factory and Workshop Act, 1901, requires every medical practitioner attending on or called in to visit a patient whom he believes to be suffering from lead, phosphorus, arsenical or mercurial poisoning, or anthrax, contracted in any factory or workshop, to notify the Chief Inspector of Factories, and a similar obligation is placed on the occupier to send written notice of every case to the inspector and certifying surgeon of the district.

The table on p. 222 shows the number of reports included in returns for the years 1900-12.

Cases of acute poisoning in factories and workshops are reportable to the Inspector and certifying surgeon, under the Notice of Accidents Act, 1906, when (_a_) causing loss of life or (_b_) due to molten metal, hot liquid, explosion, _escape of gas_ or steam, and so disabling any person as to cause absence throughout at least one whole day from his ordinary work.

The following table gives indication of the relative frequency of cases of poisoning from gases and fumes, although some were reported as accidents the result of the unconsciousness induced:

+-------------------------------+-------+------+------+------+------+
| Nature of Gas or Fumes. | 1912. | 1911.| 1910.| 1909.| 1908.|
| (1) | (2) | (3) | (4) | (5) | (6) |
+-------------------------------+-------+------+------+------+------+
|Carbon monoxide |91 (14 |64 (6 |53 (9 |53 (6 |55 (5 |
| (_a_) Blast furnace |33 (5 |16 (2 |19 (7 |16 |26 (3 |
| (_b_) Power (suction, | | | | | |
| producer, Mond, Dowson). |19 (4 |31 (1 |25 |25 (4 |19 (2 |
| (_c_) Coal |29 (2 | 6 (2 | 4 |11 (1 | 9 |
| (_d_) Other |10 (3 |11 (1 | 5 (2 | 1 (1 | 1 |
|Sulphuretted hydrogen | 6 | 8 (2 | 2 | 5 (2 | 8 (1 |
|Carbon dioxide | 3 (2 | 1 (1 | 2 (1 | 2 (2 | 4 (3 |
|Ammonia | 1 | 1 (1 | 2 | 1 | 1 |
|Chlorine and hydrochloric | | | | | |
| acid fumes | 3 | 5 (1 | 3 | 1 | 1 |
|Nitrous fumes |12 (1 |18 (2 |11 |12 (2 | 3 (1 |
|Nitro and amido derivatives of | | | | | |
| benzene | 9 (1 |21 |18 | 4 | 2 |
|Naphtha and benzene | 3 (1 | 1 (1 | — | 1 (1 | 2 |
|Other (Sulphur dioxide, &c.) | 7 (2 | 4 | 4 | 4 | 3 |
+-------------------------------+-------+------+------+------+------+

The principal figures are those of all cases, fatal and non-fatal; the small figures relate to fatal cases.

Transcriber’s Note: The ‘small figures’ are given here in brackets e.g. (1.

[E] The principal numbers relate to cases, the small figures to deaths. Fatal cases not reported in previous years are included as both cases and deaths.

Transcriber’s Note: The ‘small figures’ are given here in brackets e.g. (1.

[F] Fischer adopts a chemical basis in his classification. His two main subdivisions are (1) inorganic and (2) organic poisons. The sub-divisions of the inorganic poisons are (_a_) non-metallic—chlorine, calcium chloride, hydrochloric acid, potassium chlorate, hydrofluoric acid, carbonic oxide, phosgene, carbon dioxide, cyanogen compounds, ammonia, nitrous fumes, phosphorus, phosphoretted hydrogen, arsenic compounds, antimony compounds, sulphur dioxide, sulphuric acid, sulphuretted hydrogen, carbon bisulphide, chloride of sulphur; and (_b_) metallic—chromic acid and chromates, manganese dioxide, sulphate of nickel, mercury and lead. The sub-divisions of (2) the organic substances are into (_a_) the unsaturated carbon compounds—benzene, petroleum, methyl-, ethyl-, amyl-, and allyl-alcohol, oxalic acid, formal- and acetaldehyde, acrolein, acetone, methyl-bromide and iodide, nitro-glycerin, dimethyl-sulphate and amyl acetate, and (_b_) the aromatic series benzene, nitro-, chloro-nitro-, dinitro-, chloro-dinitro-benzene, phenol, picric acid, phenyl-hydrazine, aniline, and certain aniline colours, para-nitraniline, pyridine, naphthalene, nitro-naphthalene, naphthlyamine, naphthol, benzidine, acridine, turpentine, and nicotine.

[G] A Prussian Ministerial Decree, dated March 31, 1892, deals with the preparation of nitrate of mercury.

[H] In Great Britain and Ireland the White Phosphorus Matches Prohibition Act became operative from January 1, 1910. In the United States of America a Prohibition Act became operative on July 1, 1913.

[I] Reprinted by permission of the Controller of H.M. Stationery Office.

[J] _Use of Oxygen Cylinder._—Open the valve gradually by tapping the lever key (which must first be extended to its full length) with the wrist, until the oxygen flows in a gentle stream from the mouthpiece into the patient’s mouth. The lips should not be closed round the mouthpiece. The nostrils should be closed during breathing in, and opened during breathing out.

If the teeth are set, close the lips and one nostril. Let the conical end of the mouthpiece slightly enter the other nostril during breathing in, and remove it for breathing out.

[K] The suggested regulations made after his inquiry (see p. 149) by Dr. Copeman are:

1. Ferro-silicon should not be sent out from the works immediately after manufacture, but after being broken up into pieces of the size in which it is usually sold, should be stored under cover, but exposed to the air as completely as possible, for at least a month before being despatched from the works.

2. Manufacturers should be required to mark in bold letters each barrel or other parcel of ferro-silicon with the name and percentage grade (certified by chemical analysis) of the material; the name of the works where it is produced; the date of manufacture; and date of despatch.

3. The carriage of ferro-silicon on vessels carrying passengers should be prohibited. When carried on cargo boats it should, if circumstances permit, be stored on deck. If it be considered necessary to store it elsewhere, the place of storage should be capable of being adequately ventilated, and such place of storage should be cut off by airtight bulkheads from the quarters occupied by the crew of the vessel.

4. This regulation should apply to the transport of ferro-silicon on river or canal barges as well as on sea-going vessels.

5. Storage places at docks or at works where ferro-silicon is used should have provision for free access of air, and should be situated at a distance from work-rooms, mess-rooms, offices, &c.

[L] Regulations 5-7 contain precautions to be observed in the corroding chambers.