Respiratory protection - 688 entries found
Your search criteria are
Harris H.E., DeSieghardt W.C., Burgess W.A., Reist P.C.
Respirator usage and effectiveness in bituminous coal mining operations.
After a brief review of the past and likely future developments in this field, the authors present a progress report on an in-mine research project on respirator efficiency. Respirable dust concentrations outside and inside the facepiece of 5 models were measured in 5 subjects (mining machine operator, loading machine operator, shuttle car operator, roof bolter, non-miner). The ratio between the 2 concentrations yielded an Effective Protection Factor (EPF). Very different EPFs, ranging from 9.0 in mining machine operators to 3.2 in roof bolters, were obtained. One reason for the little use made of respirators in daily mining practice is that a man cannot remove his hard hat with lamp and cord attachment in order to position the head harness of the respirator in the recommended manner. On the whole respirators are worn only when dust is visible to the miners.
American Industrial Hygiene Association Journal, Mar. 1974, Vol.35, No.3, p.159-164. Illus. 5 ref.
Use of pesticides - Protection of respiratory tract
Emploi des pesticides - Protection des voies respiratoires. [in French]
This note warns against the risks inherent in the use of pesticides and the inefficacy or limited service life of certain protective masks. Equipment fitted with filters against specific substances offers effective protection against toxic mists caused by spraying of pesticides. Selection of respiratory protective equipment according to the product employed, the way it is applied, and the conditions of use (protective filters for products used for gassing and for fine powders, self-contained equipment such as masks with fresh air supply or compressed air pipe for work in confined spaces).
Cahiers de notes documentaires - Sécurité et hygiène du travail, 3rd quarter 1974, No.76, Note No.916-76-74, p.413-417. Illus. 1 ref.
Kostanecka I., Mańkowska W., Sawicka A.
Study of the protective efficiency of sorbent-filter respirators and combined sorbent-particulate filter respirators against liquid organophosphorus insecticides
Badania przydatności pochłaniaczy i filtropochłaniaczy jako ochron stosowanych przy pracach z płynnymi insektycydami fosforoorganicznymi [in Polish]
Study of the relative merits, as means of protection against liquid organophosphorus insecticides, of 4 sorbent filter respirators and 6 combined sorbent-particulate filter respirators manufactured in East Germany, West Germany, Italy and Poland. The parameters compared were: weight of respirator; weight and volume of sorbent material; breathing resistance; relative filtration efficiency of the respirators for different insecticides. The comparative analysis of the results indicates that the combined sorbent-particulate filter respirator is superior to the plain sorbent filter respirator. Numerous comparative tables are given.
Prace Centralnego instytutu ochrony pracy, 1974, Vol.24, No.80, p.21-37. Illus. 12 ref.
Smith D.L., Giesler W.S.
An evaluation of organic vapor respirator cartridges and canisters against vinyl chloride
Report on the procedure, setup and results of laboratory tests on the life service of 4 types of approved organic vapour respirator cartridges and of 4 types of approved front- or back-mounted organic vapour gas-mask canisters relative to several concentrations of vinyl chloride. Various mixtures of vinyl chloride gas and air were passed through the cartridges and canisters. The downstream concentration was monitored until breakthrough occurred. The effect of concentration on breakthrough time conformed to absorption theory. Service life increased at low humidities and decreased at high humidities. Organic vapour respirator cartridges have a service life of 20min at vinyl chloride concentration below 50ppm. The service life of the canisters is 100min at concentrations below 100ppm. Facepiece leakage is expected to be 10% for a half-mask respirator and 1% for a full-facepiece respirator.
HEW Publication No.(NIOSH)75-111, National Institute for Occupational Safety and Health, Office of Technical Publications, Post Office Building, Cincinnati, Ohio 45202, USA, Oct. 1974. 23p. Illus. 5 ref. Gratis.
Return to the standard helmet outfit?
Rückkehr zum Helmtauchgerät? [in German]
Exposition of the technical grounds and safety aspects which caused the standard helmet outfit to fall into disfavour to some extent. To meet the objections raised to this type of diving equipment, helmet outfits affording greater mobility were developed, satisfying to some extent the need for more polyvalent all-purpose equipment, due to reduction in volume of the helmet. Description of a diving outfit of this type.
Drägerheft, Apr.-June 1974, No.296, p.8-14. Illus.
De V. Martin H., Callaway S.
An evaluation of the heat stress of a protective face mask.
This paper examines the physiological response of a group of 4 trained volunteers working for 120min in a warm environment (DB/WB 34/25.5°C) while wearing each of 2 clothing assemblies, with and without the current UK NBC S6 respirator. The men were given 10 days training and heat acclimatisation before commencing the tests. It was found that the face mask imposes a significant additional heat stress, which when measured by the physiological responses of the wearer increases with the level of the prevailing stress.
Ergonomics, Mar. 1974, Vol.17, No.2, p.221-231. Illus. 5 ref.
Recommendations for the selection, use and maintenance of respiratory protective equipment.
Where there is a risk of workers inhaling dangerous substances, the first consideration should be to protect them by automating, enclosing, exhausting or ventilating the equipment. When this is impossible, respiratory protective equipment is essential. These recommendations describe in general terms the various types of such equipment, discuss the factors affecting its choice and make recommendations for selection, use and maintenance.
BS 4275:1974, British Standards Institution, 2 Park Street, London W1A 2BS, United Kingdom, Apr. 1974. 21p. Illus. 5 ref. Price: £2.00.
Christmann H., Gabriel J.M., Lardeux P.
Efficiency and comfort of personal filter apparatus for protection against dust
Efficacité et confort des appareils filtrants de protection individuelle contre les poussières. [in French]
Description and results, with comments, of approval tests carried out on 48 models of dust masks marketed in France in 1973. The tests covered physical (pressure drop, efficiency and clogging) and physiological features (decreased field of vision, dead space). A separate data sheet gives the results obtained by each of the 15 masks which passed the tests. Tests on the impermeability of facepieces will be the subject of a subsequent communication.
Travail et sécurité, Sep. 1974, No.9, p.394-416. Illus.
Strindberg L., Johansson L., Carlsson A., Ljungqvist E., Åstrand I.
Physiological load due to increased breathing resistance while wearing a filter respirator
Fysiologisk belastning vid ökat andningsmotstand orsakat av andningsskydd [in Swedish]
12 young and 12 older healthy men performed exercise on a bicycle ergometer with and without a respirator. Work intensities were 50, 75, 100 and 125W and the exercise periods were 5min with a respirator, with an ordinary valve (for reference), and with free breathing. Older subjects had a higher mean value for pulmonary ventilation and a lower mean carbon dioxide level than the young subjects; they also had a significantly higher negative pressure in the mask at the 2 heaviest work loads. Young subjects experienced greater respiratory resistance in breathing through a respirator than in breathing through a valve at the 2 heaviest work loads. It is therefore recommended that respirators, such as MSA Comfo, should not be used in work calling for pulmonary ventilation rates higher than 40 l/min.
Arbete och hälsa - vetenskaplig skriftserie, 1974:5. Arbetarskyddsstyrelsen, Fack, 100 26 Stockholm 34, Sweden, 1974. 28p. Illus. 13 ref. Price: Swe-cr.8.00.
Handl E.H.H., Oppers V.M.
The influence of compressed-air breathing apparatus on pulse rate and systolic pressure of firemen performing physical work
Invloed van persluchtapparatuur op polsfrequentie en systolische bloeddruk tijdens belasting bij brandweerlieden [in Dutch]
Results of bicylce ergometer tests carried out on 30 healthy firemen between 31 and 55 years of age, with and without compressed-air breathing apparatus. It was clearly demonstrated that subjects over 45 years of age show a diminishing heart-rate response at the highest workload, although their systolic pressure remained unchanged. Firemen over 45 years should avoid excessive physical effort while wearing a compressed-air respirator.
Tijdschrift voor sociale geneeskunde, 22 Feb. 1974, Vol.52, No.4, p.118-121 and 133. Illus. 1 ref.
Petit J.M., Schewe A., Hausman A.
Research for the improvement of the physiological conditions of breathing apparatus.
Translations of 3 articles, "Recherches visant à améliorer les conditions physiologiques des appareils respiratoires". Revue de l'Institut d'Hygiène des Mines, Hasselt, Belgium, 1971, Vol.26, No.1, p.3-11, 12-16, and 17-23. Up to 13 self-contained breathing appliances were tested (liquid oxygen apparatus with soda lime regeneration, compressed oxygen apparatus with caustic soda regeneration, and compressed oxygen apparatus with soda lime regeneration). No.6362 (Petit) demonstrates the possibility of improving CO2 absorption and reducing the thermal load in hot environments by means of CO2-cooled protective clothing. Diagrams for estimating the overall physiological effects of a "good" and a "bad" respirator are reproduced. No. 6363 (Schewe) presents a method of simulating the use of self-contained breathing apparatus, using an artificial lung. Results obtained with ventilation rates of 10 and 50l/min are compared with those obtained in a human subject. No.6364 (Hausman) reports results of tests in 300 rescue workers with a wet-bulb temperature of up to 34°C. A definite improvement of the compressed oxygen appliances was obtained by cooling with solid CO2.
SMRE Translation No.6362, 6363, 6364, Department of Trade and Industry, Safety in Mines Research Establishment, Red Hill, Broad Lane, Sheffield S3 7HQ, United Kingdom, Dec. 1973. 15, 10 and 13p.
Assessment of organism efficiency while working in breathing apparatus.
Translation of: Ocena wydolności organizmu podczas pracy w aparatach ochrony dróg oddechowych. Prace Centralnego instytutu ochrony pracy, Warszawa, Poland, 1971, Vol.21, No. 71, p.319-333. Illus. 24 ref. Report of a study on the physiological effects of respiratory protective equipment, in which heart rate, blood pressure, face-skin temperature, energy expenditure, etc. were measured. Field tests in 18 workers at 2 plants and bicycle ergometer tests in 7 students are described. The types of facemask used are presented and the results are shown in graph form and discussed. Conclusions are drawn on the design of equipment (improvements to reduce breathing resistance and mask weight, to increase field of vision, etc.) and on hours of work and work breaks for persons wearing various types of mask and doing different jobs.
Royal Aircraft Establishment, Farnborough, Hants, United Kingdom. N74-26630/5WJ, National Technical Information Service, Springfield, Virginia 22151, USA, May 1973. 19p. Illus. 24 ref. Price: Photocopy US-$4.00/Microfiche US-$1.45.
Bretschneider K., Fahnert R., Otto J., Stapf F.
Determination of the retention capacity of respiratory protective filters for solvents and mixtures of solvents in laboratory conditions.
Bestimmung des Rückhaltevermögens von A-Kohle-Atemschutzfiltern für industriell bedeutsame Lösungsmittel und Lösungsmittelgemische unter Laborbedingungen [in German]
Account of a study on the retention capacity of activated charcoal respiratory protective filters for ethanol, ethyl acetate, benzene, n-butanol, butyl acetate, n-heptane, methanol, methylene chloride, n-propanol, iso-propanol and trichloroethylene. Experimental conditions and methods are described and the results are tabulated. Comments are made on the loss of efficiency of the filter, which did not occur all at once, but gradually. Of all the substances studied, methanol was an exception because of the small quantity which could be adsorbed. Consequently, the use of activated charcoal filters for protection against methanol or solvents containing methanol is limited to emergencies.
Zeitschrift für die gesamte Hygiene und ihre Grenzgebiete, July 1973, Vol.19, No.7, p.491-493. 3 ref.
Selig R., Mährlein W., Schettler R.
Effect of dust respirators on miners' work capacity
Der Einfluss von Staubschutzmasken auf die Leistungsfähigkeit des Bergmannes [in German]
An account is given of the results of measurements carried out on 22 healthy subjects tested on a bicycle ergometer. Of all the biological indices measured, the heart rate was the most significant. With a dynamic strain of 75W maintained for 1h, the wearing of a protective mask did not lead to any lowering of output. Furthermore, the maximum output was reached sooner with the mask than without the mask, but only from 9.30kcal/min, a level which, in practice, is only recorded for short periods of time. The unfavourable effect of high temperature on cardiovascular regulation during exercise should be noted.
Atemschutzinformationen, 1973, Vol.12, No.2, p.25-29. Illus. 5 ref.
Artemenko A.I., Kozačenko V.V.
Apparatus for testing the airtightness of self-rescue respirators
Pribor dlja proverki germetičnosti samospasatelej [in Russian]
Description of the construction and operation of an air-chamber apparatus developed by a Soviet mining institute to test the airtight qualities of 2 models of self-rescuers manufactured in the USSR. The dial indicator of the apparatus is housed in a hermetically-sealed case; thus any variations in atmospheric pressure due to mine ventilation do not affect the precision of readings.
Bezopasnost' truda v promyšlennosti, Sep. 1973, No.9, p.40. Illus.
Chrétien L., Le Bourdonnec Y., Werderer B.
Determining the respiratory work rate of a person wearing respiratory protective equipment
Détermination de la puissance respiratoire dépensée par le porteur d'un appareil de protection respiratoire. [in French]
It is important to know the additional respiratory work rate imposed on the lungs when respiratory protective equipment is worn, because it affects workers' capabilities. The various experimental methods proposed by several research workers are described and compared. 3 types of apparatus used at the Saclay Nuclear Study Centre (filter apparatus, open and closed-circuit self-contained breathing apparatus) were studied, using a dynamic method. The appliances are classified according to the type of work for which they are suitable.
Note CEA-N-1681, Atomic Energy Commissariat, Saclay Nuclear Study Centre (Commissariat à énergie atomique, Centre d'études nucléaires de Saclay), Boîte postale No.2, 91190 Gif-sur-Yvette, France, Dec. 1973, 54p. Illus. 12 ref.
Standard for identification of air-purifying respirator canisters and cartridges.
This standard establishes a system for the marking of air-purifying canisters and cartridges for use in respiratory protective equipment. The primary means of identification shall be properly-worded labels, supplemented by an identifying colour or colours. A list is given of atmospheric contaminants against which canisters or cartridges may give protection; an identifying colour is given for each contaminant. The standard wording that should appear on each canister or cartridge label is reproduced.
ANSI K13.1-1973, American National Standards Institute, 1430 Broadway, New York, N.Y. 10018, USA, 21 Feb. 1973. 7p. 2 ref. Price: US-$3.00.
Atemschutz [in German]
The articles by various authors in this issue devoted to respiratory protection cover the following aspects: incorrect conceptions concerning respiratory protection (indicates correct use of respiratory protective equipment); physical aptitude to wear heavy self-contained breathing apparatus; training in the use of respiratory protective equipment; working of compressed-air respirators and oxygen respirators; use of filter respirators.
Sicherheitsingenieur, May 1973, Vol.4, No.5, p.206-229. Illus.
Abrasive blasting respiratory protective practices survey - Final report.
A report produced under contract for the National Institute for Occupational Safety and Health. A postal survey of the degree of respiratory protection provided for workers in abrasive blasting operations in 3,903 firms (masonry, foundries, etc.) in specific areas of 5 States of the USA is described, and the results obtained are indicated. A representative sample of these firms was selected for on-site survey and monitoring. This on-site survey comprised an interview, the determination of the nature and concentration of dusts to which abrasive blasters were exposed and also noise level measurements. The results showed that typical operations are dry-blast by hand-held hose using silica sand on steel or stone in an open area with limited respiratory protection. Approximately 70% of the work resulted in silica dust generation. A wide range of protective equipment was used and the degree of protection provided by each individual type varied considerably; little effort was made to ensure good fit; blasting helmets were found to be poorly designed. No effective supervision of the use of protective equipment was found. Recommendations on improved equipment and practices are given.
Report D195-10012-1, Boeing Aerospace Company, Seattle, Washington 98124, USA, 31 Aug. 1973. 122p. Illus. 19 ref.
Crooks T.P., Stawitcke F.A., Tobey S., De Cola C.R.
An air-supplied respirator for underground coal miners.
Final report on a research project undertaken for the National Institute for Occupational Safety and Health. Describes a newly developed supplied-air respirator for coal miners in which the air-supply and air-cleaning systems are mounted on the mining equipment which the wearer is operating, and which utilises the power available on the machine for overcoming breathing resistance in the respirator. The requirements for the development of the new equipment are analysed and the individual components of the system are detailed with particular reference to a new facepiece design, the development of a suitable demand regulator, the air distribution components, the dust removal components and the motorcompressor system. Trials have shown that this new design is more readily acceptable to miners than conventional equipment.
Technical Report 73S-3, Synsis Inc., Los Angeles, California 90065, USA, June 1973. 194p. Illus. 31 ref.
Bajer B., Furs S., Kopczyńska T.
Principles of classification of filter papers used in the protection of the respiratory tract against dust
Zasady klasyfikacji bibuł filtracyjnych stosowanych w przeciwpyłowych ochronach dróg oddechowych [in Polish]
Comparative evaluation of filter papers used in filter respirators according to 3 coefficients (filtration efficiency, flow resistance and dust absorption). 8 types of commercially produced filter papers from various countries were classified according to a quality index based on these coefficients and by a diagrammatic method. Results are presented in the form of graphs and tables
Prace Centralnego instytutu ochrony pracy, 1973, Vol.23, No.79, p.333-362. Illus. 15 ref.
Workshops for the servicing, maintenance and testing of respiratory protective equipment
Die Atemschutzwerkstatt [in German]
Considerations and principles concerning the design, construction and equipment of these workshops.
Sicherheitsingenieur, Aug. 1973, Vol.4, No.8, p.370-373. Illus.
Data sheet on respiratory protection
Atemschutzmerkblatt [in German]
Provides information on the uses of respiratory protective equipment for specific purposes and examines various types of equipment of this kind. Sections are devoted to: general provisions; categories of respiratory protective equipment; advice on selecting equipment; facepieces; respiratory protective equipment depending on the surrounding atmosphere (filter equipment). A commentary of this data sheet is given in Staub, Düsseldorf, Germany (Fed.Rep.), Aug. 1973, Vol.33, No.8, p.332-335.
ZH 1/134, Federation of Industrial Mutual Accident Insurance Associationns (Hauptverband der gewerblichen Berufsgenossenschaften), Bonn. Karl Heymanns Verlag KG, Gereonstrasse 18-32, 5 Köln 1, Germany (Fed.Rep.). 16p. 7 ref.
Bentley R.A., Griffin O.G., Love R.G., Muir D.C.F., Sweetland K.F.
Acceptable levels for breathing resistance of respiratory apparatus.
Tolerance of additional external resistance to inspiration was investigated in 158 mine rescue workers during exercise. Peak inspiratory pressure, minute volume and respiratory work rates were calculated to assess correlations with subjective tolerance (determined by questionnaire). A method of defining an acceptable limit for inspiratory resistance is presented. The results indicate that 90% of a population breathing through apparatus with low-resistance expiratory valves should experience no discomfort if the pressure across the apparatus does not exceed 17 cm of water.
Archives of Environmental Health, Oct. 1973, Vol.27, No.4, p.273-280. Illus. 18 ref.
Pulse rate tests while wearing respiratory protective equipment
Untersuchungen der Pulsfrequenz beim Tragen von Atemschutzgeräten [in German]
Pulse rate was measured by the photoelectric method by light passing through the lobes of the ear, first at rest (lying down) and then wearing a compressed air respirator while exercising on a treadmill. The results of the tests are given in diagrammatic form and discussed. With one type of equipment, a maximum pulse rate of 99/min at exercise was found, denoting physical overload.
Drägerheft, Apr.-Sep. 1973, Vol.292-293, p.32-35. Illus. 3 ref.
Effect of weight of respiratory protective equipment on volume of air required for breathing
Einfluss des Gewichtes von Atemschutzgeräten auf den Atemluftverbrauch [in German]
Experimental study of the parameters which increase discomfort in wearing respiratory protective equipment. The experiments were carried out with an air-supplied hose mask, weighing 1.5 kg, and 2 different types of compressed air-breathing apparatus, weighing 15 and 20 kg respectively, the subject doing walking and running exercise on a treadmill. Respiratory minute volume and pulse rate were measured. It is concluded that the weight of respiratory protective equipment should not exceed 15 kg.
Drägerheft, Apr.-Sep. 1973, Vol.292-293, p.36-44. Illus. 4 ref.
Mine rescue apparatus Scott/Draeger-BG 174.
This guide is intended to assist instructors in enabling trainees unfamiliar with the Scott/Draeger-BG 174 mine rescue apparatus to learn the proper operation and care of the equipment. Chapters cover: suggestions to the instructor; outline of the course; construction, testing and wearing of the apparatus. The course is supplemented by a questions and answers section. Physical fitness and physician's examination forms are appended, together with information on rescue station equipment, Scott/Draeger periodic tests and individual training records.
Instruction Guide 21, Bureau of Mines, Publications Distribution Branch, 4800 Forbes Avenue, Pittsburgh, Pennsylvania 15213, USA, Oct. 1972. 47p. Illus. 11 ref. Gratis.
Webb Associates, Yellow Springs, Ohio.
Anthropometry for respirator sizing.
Final report of an anthropometric research carried out to establish parameters for the correct sizing and design of dust respirators. It is concluded that, although an adequate source of head and face anthropometry based on industrial workers does not exist, the US Air Force surveys of 1967 and 1968 are satisfactory for the design and sizing of respirators for industrial workers. Differences in the head and face size of racial and ethnic subgroups are of little practical significance in respirator design. A variety of sequential sampling procedures for testing masks are described; the extensive data that constitute the results are appended.
National Institute for Occupational Safety and Health, Cincinnati, Ohio 45202, USA, 30 Apr. 1972. 112p. Illus. 32 ref.
New pocket-size respirator filter table
Neue Tabelle für Atemfilter - im Taschenformat [in German]
In connection with efforts to reduce the number of types of respirator filter, a new recapitulative table of respirator filters has been published. This table refers only to gas filter types A, B, E, K and CO. Since the range of protection offered by the B filter has been significantly extended, filter types F, G, J, L, O and R have been replaced by the B-filter which now offers protection against prussic acid, hydrogen sulfide, arsine and phosphine in addition to acid gases and combustion gases.
Drägerheft, Jan.-Mar. 1972, No.287, p.30. Illus.
Calculation of human thermal regulation and the effect of an inhaled-air cooler
Berechnungen zum Wärmeverhalten des Menschen und der Einfluss eines Atemluftkühlers [in German]
Heat generation in the human body and respiratory heat exchange in a person wearing respiratory protective equipment are theoretically considered in relation to the permissible length of exposure to adverse environmental conditions. Particularly significant factors are internal body temperature and the cooling effect of the environment. A number of diagrams are given. The effect of an inhaled-air cooler is evaluated (dry ice in the inhalation hose of a recirculating air respirator).
Atemschutzinformationen, Apr. 1972, Vol.11, No.1, p.1-5. Illus. 9 ref.
Respiration cartridge efficiency studies
Part I (Experimental design) describes the apparatus and test materials developed and used for determining the service life of respirator cartridges in atmospheres containing organic vapours. The cartridges are placed in a holder, and breakthrough times are determined by measuring the upstream and downstream concentrations. Breakthrough characteristics can be ascertained by using either a steady-state flow or a cycling flow produced by a breath simulator. Part II (Preparation of test atmospheres) describes the design and operation of the apparatus used to produce test atmospheres of known composition. Concentrations from 1 to more than 1000ppm can be generated at variable airflows, and humidity can be adjusted from 1 to 95%.
American Industrial Hygiene Association Journal, Feb. 1972, Vol.33, No.2, p.105-116. Illus. 32 ref.
Hughes J.G., Lomaev O.
An anthropometric survey of Australian male facial sizes
An anthropometric survey was carried out among 538 men in both a general and an industrial population with a view to obtaining basic data for the design of respirators. The results ar presented and discussed, mean values and standard deviations being given for 8 facial dimensions. Small but significant differences exist between Australian-born, United Kingdom-born, and other foreign-born groups.
American Industrial Hygiene Association Journal, Feb. 1972, Vol.33, No.2, p.71-78. Illus. 7 ref.
Recent progress in self-contained respiratory protective equipment
Neuentwicklungen für den umluftunabhängigen Atemschutz [in German]
A comparison of demand-type and rebreathing-type self-contained respiratory protective equipment (weight, length of use) comes out in favour of the rebreathing-type apparatus. By raising the operating pressure to 300 bars, it has been possible to increase the service time of demand-type respirators and at the same time reduce their weight. It has also been possible to reduce the weight of rebreathing-type respirators. Advice is given on the use of this type of apparatus. A mixed-gas rebreathing apparatus (60% oxygen, 40% nitrogen) has been developed for use in pressurised atmospheres.
Arbeitsschutz, June 1972, No.6, p.240-242. Illus.
Lower breathing impedance of self-contained, closed-circuit respirators
Description of 2 systems intended to reduce the impedance to breathing in portable breathing apparatus used in firefighting and in low-oxygen environments. Both require additional power sources to drive a fan and/or electronic and electromagnetic components and require small oxygen storage tanks. The first system uses a fan to move the air through the major sources of resistance, whereas the second uses electronically controlled active valves. A prototype of the first system was built; the preliminary results indicate a substantial lowering of breathing resistance. The second system was studied by digital simulation, and the results are presented in detail.
American Industrial Hygiene Association Journal, July 1972, Vol.33, No.7, p.441-448. Illus.
Reist P.C., Cole H.M.
A simple procedure for the routine testing of respirator sorbents
Description of a simplified procedure for testing respirator sorbents for breakthrough, using chemical detector tubes in place of sophisticated analytical methods. The apparatus consists mainly of a test gas bottle, glass tubing, valves and meters, a cartridge holder and a detector tube suitable for the test gas concerned. The detector tube is used qualitatively only to measure breakthrough time. Experiments carried out with SO2 sorbent cartridges showed good agreement with the standard ASTM electrical conductivity method.
American Industrial Hygiene Association Journal, Aug. 1972, Vol.33, No.8, p.523-525. Illus. 3 ref.
Gannoe R.E., Riley G.R., Frink D.W.
Battelle Memorial Institute
Interim report on gas monitoring equipment investigation
Twenty-two instruments available in the USA to detect and measure the essential and also the potentially harmful gases contained in a diver's breathing system were reviewed in relation to characteristics, performance and conditions of use in diving operations. The gases selected were: oxygen, carbon dioxide, carbon monoxide, water vapour (relative humidity), hydrocarbons, oxides of nitrogen, sulphur dioxide and halogen compounds. The report is in 3 parts: breathing gas constituents; gas monitoring techniques; and gas monitoring equipment. Of the various techniques available, gas chromatography appears to be the most promising for a number of constituents. An appendix is devoted to psychrometric calculations for diving applications. Manufacturers' bulletins are reproduced.
National Technical Information Service, Springfield, Virginia 22151, USA, 1971. 122p. Illus. 12 ref.
Craig F.N., Blevins W.V., Froehlich H.L.
Training to improve endurance in exhausting work of men wearing protective masks - A review and some preliminary experiments
A brief survey of the relevant literature is followed by the description and results of experiments carried out to evaluate the influence of training on endurance when performing exhausting work while carrying a protective mask. The men wore the masks with filters removed and with various inspiratory and expiratory resistance added. It was found that even without the filter, the facepiece has a degrading effect on endurance. Physical fitness was shown to be an important factor in endurance in masked men. Small differences in expiratory resistance had no effect on endurance.
Medical Research Laboratory, Edgewood Arsenal, MD 21010, USA, July 1971. 24p. 24 ref.
Respiratory protective equipment
Atemschutzgeräte [in German]
Appareils de protection respiratoire [in French]
This information note describes the types of hazards which require workers to wear respiratory protection - oxygen deficiency, gaseous and particulate contaminants. Different types of respirators are described along with their limitations, precautions in their use and inspection and maintenance requirements.
International Occupational Safety and Health Information Centre (CIS), International Labour Office, 1211 Genève 22, Switzerland, May 1964. 33p. Illus.
< previous | 1... 9, 10, 11, 12, 13, 14