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FILE NAME State of the Art Literature SAL DATE 1930 DOC SAL008 DOCUMENT DESCRIPTION Excerpt - Encyclopedia of Hygiene Pathology and Social Welfare - Asbsetos oe 3 vrs ae ceatin * ee eerat, LS fem, COREeas iarz, ae fs > ww r, 5 Oeant Hes oe ae . ee SI thFioeg an iy oe 2 17 INTERNATIONAL LABOUR OFFICE 1930 1930 24 OCCUPATION HEALTH ENCYCLOPAEDIA OF HYGIENE PATHOLOGY AND SOCIAL WELFARE Volume I A . : i FOR vyot ve a EASoe MEDIT PLANS PLANS PLANS PLANS PLANS PLANS pbiaeh No. No. A. 9A. NE y 1 SS J o& SQx %, $ \ Yo GENEVA 1930  ISD ASHESTO ASHESTO ee qualit the mayor which must be week The Californian renewed avery law no child under at least 16 enjoins that can be employed in years of age a authorised and after studio unless duly medical examination carried out by a medical man in the Child Welfare Service These examinations are mada every three months Children tak- ing part in film production must not be employed more than eight bours a day Including less less lasting four hours given by a eacher paid but not selected by the - udios Employment of children before 8 a.m. and after 5 p.m. is prohibited BIBLIOGRAPHY in open having ih galleries; quarries or in countries severe winter climate in 2 separation of the ashes tos from rock is the cut surrounding rock The in terraces sometimes reaching a depth of some 150-200 ft Quarrying is more economical and effective than underground work evan despite exposure to weather Drilling and blasting are engaged in as in ordinary stone quarrying The miner- al got from the quarry is rough sorter ifferent grades being chosen for length of Abre and sent to " cobbing sheds where dressing is carried out PERI * La patologia artisti draINATICL Florence professionale degli I kamaszint 1913 For other sources see Bibliography of Industrial Hygiene published terly by the quar- INTERNATIONAL LABOUR OFFICE This consists of separating the abestos fibres from the surrounding rock and may be done a by hand - the stone being broken by a small st^,diga hammer and the fibre thrown there after into one box and the waste into another - or b by machine " mills ** Ben Asbestos French Amiante Asbeste Pierre ^ caton - German asbest Amianth Beryfluchs Italian and Spanish Amianto Chemical Properties Asbestos is a brilliant filamentous min- eral oily to the touch white silvery grey greenist or bluish Its density is 2.3.2.9 Its chemical composition consists accord- ing to its origin of calcium silicate ant magnesia or of magnesia silicate accoin panied by quantities of iron more or less extensive Analysis of different varieties of asbestos reveals a silica 40-50 per cent content - -41.2 in Canadian of 41.8 in Siberian asbestos and asbestos 51.1 African variety - while oxide of in the vartes between 2.3 African magnesia and 41,7 Canadian oxide of iron between 2.32 Canadian and 35.8 African In Siberian asbestos there is besides 18.39 per cent of alumina When cut up it presents cotton form which lends a silky itself to weaving It is easily incombustible prevents heat loss is a thermic and electric insu- lator and is not attacked by most acids Of the three different mineral known by the name of asbestovsariiettieiss serpentine asbestos or chrysolita and hornblende asbestos which are the commonly used the first of these most is most sought after the asbestos variety Tadastr~-n~- Russia Itisalcyhiaenfldy tdheeriTvreadnsfvraoianl Cana; ula Hand separation " picking and sorting is not difficult since the filires lic in layers more 05 less loosely attached to the rock and can frequently he picked off with the fingers lat hand dressing is not thorough and the waste material from the cobbing tables contains much fibre the further utilisation of which represents Burge profits to the mine and these fine pickings have to be dressed mechanic- ally They are passed after drying In crushers where they are broken by successively finer rollers and fur ther reduced by cylindrical fil^risers and the cyclone machine which rn. duces them to fine powder The cotton- like fibres come to the surface and are mechaniently withdrawn by suction The pulverised rock and ground asbestos are then separated by passing them through a shaking screen In some mills the particles of iron present are taken up by strong electric magnets The crude fibre on separation from the waste rock resembles resembles mineralised wool The asbestos is graded according to the length of fibre on a series of cylindrical screens It is then carded and packed in sacks and placed on the market in bulk INDUSTRIAL Uses The uses to which are very varied The asbestos is put long ^ bres are used in the textile industry for the manufacture of cloth braul rone theatre curtains deenration Tbs e TECHNOLOGY Extraction involves two distinct operations bearing ! quarrying the asbestos rock generally mined timistuing stery hangings and tor pistons for steam engines The shorter fibres agent together with an agglomerating are used in the manufaetura manufaetura frit paper cardboard ViPS strong covering agents especially for strong Nel 4 ASBESTOS ; we 190 rooms cements rubber tyres for autoniobiles and bicycles Asbestos is also used 13 an electrical insulator for covering electric wiring for high and low pressure currents in the manufacture of tiles planks panelling and exterior coverings for buildings maitresses heat insulating gloves firemen's clothes laboratory equi ment porcelain bails for gas fires made of fireclay and asbestos etc. DANGERS AND HYGIENE The worker engaged on the extraction and manufacture of asbestos is constantly exposed to danger fran itust intore especially however weav- in the operations of spinning and weav- See also article " Tuberculosis In an asbestos wenving factory in Saxony the workers complained of headaches and loss of appetite . These affections were caused by fumes given off by a rubber solution with which the ashes- tos cloth dust had been coated to eliminate An investigation carried out in Can- ada in 1911 revealed that hygienic conditions were greatly improved as a result of the adoption of an effective system of ventilation Nevertheless a local doctor with long experience stated that respiratory troubles and very in particulur tuberculosis were of fremment occurrence amongst asbestos workers Rambousek drew attention to the risk ing The baneful influence of the dust in reintion to the production of tuberenlosis is brought out in the Annual Report of the Chief Inspector of Fnetories for England and Wales for 1910 which records 5 deaths from tuberculosis amongst 40 Workers engaged in an asbestos weaving fac tory where the most dangerous pro cess was revealed to be the weaving of asbestos mattresses composed of of lead poisoning during the weaving of asbestos when a thread of lead is added to the welt as is sometimes the case ; Marked frequency of chronic con- junctivitis with hypertrophy of the rims of the pupils has also been noted amongst the asbestos workers of the Island of Cyprus The workers in question were chiefly engaged in grind ing screening and packing the asbestos in sacks bags of woven asbestos Alled with The weaving of asbestos has only{ THM short asbestos Abre They were placed developed importance during the last on a table and benten out fat by n twenty years Now that it is widely | man with a wooden flail which pro- practised the application of local CCSS occasioned the production of exhaust systems during such processes SPI much dust Women sewed the mat- as that above described is called for tresses into sections using asbestos All processes from extraction onwards threads and as they worked beside the unquestionably involve a considerable * . TO beaters they also of necessity inhaled hazard and American and Canadian ree auch dust life insurance companies generally Towards the beginning 192 194 24 a refuse asbestos workers on account of fatal case of poisoning by asbestos the assumed deleterious conditions in ey dust was reported at Rochdale Eng- lite industry : land The victim Was ,woman who had been employed in an asbestos factory A mortem examination revented chath as due chictly to a fibrosis of the lungs due to the inhala tion of mineral particles and in part to tuberculosis A microscopic examination of the lungs and of dust sam- ples taken from three different work- shops of the factory revealed the same black particles present in each alike in form and dimensions Another fatal case was studied in The lack of more accurate and detailed data in medical literature regarding this industry in its various branches including the utilisation of products is to be deplored in view of the evident importance of ashes- tos dust as a predisposing cause ot pulmonary tuberculosis more especi- ally since the rapidly & creasing development of industri & utilising asbestos adds greatly ne urgency of studying the conditions with a view to their amelioration 1927 by Cooke and Hill Great Britain A striking example of the noxious property of asbestos dust is instanced by the following case in an asbestos All provisions already described for withdrawal of dust should be enforced in this industry spinning and weaving factory Calva- 103 there were 40 deaths in the live LEGISLATION years 1890-1897 The mortality rate decreased considerably mortality with the installation of a good system of local ventilation over the carding machines I In Italy boys under 15 and girls under 21 years of age are excluded from workshops where dyeing and Weaving of asbestos are engaged in unless effective ASHES CINBERS CINBERS - itt ow ASPHALT means are taken to prevent the diffusion of dust throughout the atmosphere BIBLIOGRAFITY AURIBAULT L'hygi^neet la s^'curit^'dea ouvriers dans les filatures et lissages d'amiante Buil de l'Insp du Tra vau 1906 pp 120-172 Paris SIMPSON W. in Brit Med 28 May 1929 p 885. London Journ UNITED STATES DEPARTMENT OF FLABOUR BURFAU of Labour Statistics Bulletin No. 231 pp 170-180 wan Ashes Cinders French Cendres - German Aschen Italian Ceneri - Spanish Cent Ashes present probleins from the point of view of industrial hygiene not only when cinders from hearths are in question dangers from hot dust presence of certain products etc. but they especially when they are enplayed for special purposes Thus for instance treatment of goldsmiths ash by lend may cause injury by renson of the metallic dust which it liberates Hygienic measures assure covering of any openings giving on to the public streets thorough ventilation of the workshop the installation of hoods for the furnaces and cupels connected to the chimney by a strong exhaust If the treatment is effected by means of mineral acids application of measures of protection against toxic fumes is re- quired viz condensation of lend fumes Noisy machinery should be isolated and measures applied for evacuation of residues and the protection of workers from the heat and glare of the furnaces Peart ash from combustion of organic material such as shoots of vine wine lees vinasse from beetroot etc. is com- posed of impure potassium carbonate and its treatment liberates sharp piquant thick and disagreeable fumes and injures vegetation in the neighbourhood Factories should be erected at a long distance from dwelling houses and cal- cination_should cination_should be effected in closed ovens Gases and fumes should be led to special henrihs or requisite measures taken for their destruction The chimney must be a very high one It would be advisable to collect the incandescent mass of carbonate of potassium in a special apparatus so constructed that the gases can be lei to the hearth or into apparatus where they can be burnt Hoods should be installed above the evaporation boilers The water should be led to a sewer the residues require fairly frequently to be removed and can be utilised as manure By the expression dust shot with a lead content is meant the impure oxides which form on the surface of each bath containing lead or lead alloys This scum or black dross is removed as it forms and is often put aside on the floor where it becomes mixed with other substances In ap- pearance it resembles ashes hence tha French expression cendres de plomb " Kelp ash is lixiviated for the extra^ tion of the snits of potassium The ash is got by burning different kinds of weed known as kelp or wrack and thrown up on the seastuire Dried in the sun they are thereafter reduced to ashes in furnaces lined with refractory bricks The product of combustion kelp ash is in the form of a soli compuet block from which the salts of potassium are extracted The blocks are then ground and put into special apparatus for grainal dilution with water The solution is concentrated in iron boilers and poured into vats where after cooling the potassium chloride is deposited in crystals which are then subjected to purification Hygienic precautions to be_recorn- be_rcon- be_recorn- mented are impermeable flouring cement wails to the height of one metre hoods provided above the boilers to draw off the fumes to the chimney all openings to the public highways to be kept closed and neutralisation of the water used before it enters the sewers The Recommendation adopted at the International Labour Conference at Washington 1919 regarding the prolec tion lead of women and children against poisoning demands the exclusion of women and young persons under eighteen yeary of age from work involving manipulation treatment and reduction of ashes containing lead ew Mineral Asphalt Pitch Hard Bitumena French Asphalte Poir min^'rale Bitume - German Asphalt Asphalt Eripech Eripech Enthurz Enthurz Italian and Spanishi Isputter Earth and rocks unpregtiated with biti men are callest asjait In mineralogy However the name asphalt is also given to bitumen in a free state It is highly important to itistinguish between these two products Asphalt is generally in the form of fine grainnil rock black or dark brown in colour according as it is more or ess on