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2009

CIS 10-0116 Brandt M.S., Morrison T.O., Butler W.P.
Decompression sickness rates for chamber personnel: Case series from one facility
During 2004, an epidemic of decompression sickness (DCS) was observed among participants of a United States air force physiological training programme. There were 10 cases of chamber-induced altitude DCS observed. Internal and external investigations focused on time, place, person, and environment. Four were students and six were inside observers. Four were women and six men. Among the inside observers, examining the monthly exposures load against DCS suggested a dose-response relationship. Poisson regression analysis demonstrated a statistically significant 2.1-fold rise in DCS risk with each monthly exposure. Consequently, the number of exposures per month may need to be considered when devising inside observer schedules.
Aviation, Space, and Environmental Medicine, June 2009, Vol.80, No.6, p.570-573. 11 ref.

2002

CIS 03-399 Pilmanis A.A., Webb J.T., Kannan N., Balldin U.
Efecto de exposiciones repetidas a la altitud sobre la incidencia de enfermedad por descompresión (ED).
The effect of repeated altitude exposures on the incidence of decompression sickness [en inglés]
La exposición repetida a condiciones hipobáricas en el curso de una jornada durante los entrenamientos en paracaídas, entrenamientos en cámaras hipobáricas, el vuelo no presurizado y las actividades espaciales extravehiculares pueden provocar enfermedad por descompresión (ED). Para verificar la hipótesis según la cual las exposiciones breves con o sin intervalos darían como resultado una incidencia inferior de ED que una exposición única de la misma duración, 32 personas fueron expuestas a tres condiciones hipobáricas distintas: exposición continua de 2 horas (condición A, grupo de control); cuatro exposiciones de 30 minutos sin intervalo en tierra entre exposiciones (condición B); cuatro exposiciones de 30 minutos con un intervalo en tierra de 60 minutos entre exposiciones (condición C). Todas las exposiciones se realizaron a una altitud simulada de 7500 m con un 100 % de oxígeno respirable. Se examinaron los síntomas de ED y de aeroembolismo precordial (AEVP). Los resultados indicaron que las exposiciones repetidas a una altura simulada de 7500 m disminuyeron significativamente la incidencia de ED y AEVP, en comparación con una exposición única continua de igual duración.
Aviation, Space, and Environmental Medicine, June 2002, Vol.73, No.6, p.525-531. Illus. 28 ref.

2000

CIS 01-1597
Secretaría del Trabajo y Previsión Social
Norma Oficial Mexicana - Exposición laboral a presiones ambientales anormales - Condiciones de seguridad e higiene [México]
En el sumario de esta Norma: campo de aplicación (cualquier actividad de buceo o que implique un trabajo en condiciones hiperbáricas); definiciones y símbolos; obligaciones de empresarios y trabajadores expuestos; condiciones de seguridad y salud de las actividades hipobáricas e hiperbáricas (de tipo buceo); sistemas de verificación. En anexo: cuadros de descompresión y otros límites para los trabajos realizados en condiciones de presión atmosférica anormales.
Copia en Internet, 2000. 18p.+ anexos.
http://www.stps.gob.mx/04_sub_prevision/03_dgsht/normatividad/normas/nom-014.htm [en español]

1999

CIS 00-576 West J.B.
Enriquecimiento en oxígeno del aire ambiente para mejorar el bienestar y la productividad a gran altitud
Oxygen enrichment of room air to improve well-being and productivity at high altitude [en inglés]
Determinadas actividades industriales o científicas, como la explotación minera o la observación astronómica, se desarrollan cada vez más a gran altitud, pudiendo alcanzar los 5.000 m. Con frecuencia, los trabajadores acuden a estos lugares procedentes de altitudes muy inferiores, incluso desde ubicaciones a nivel del mar. Por otro lado, numerosas personas viven y trabajan permanentemente en grandes altitudes. La hipoxia de altitud altera la calidad del sueño, la aptitud mental, la productividad y el bienestar general. La inyección de oxígeno en los sistemas de acondcionamiento de aire permite aumentar la concentración de oxígeno del aire ambiente y reducir así la altitud equivalente. Un incremento de un 1 % de la concentración en oxígeno disminuye la altitud equivalente en aproximadamente 300 m; así una habitación situada a 4.500 m conteniendo un 26 % de oxígeno estaría efectivamente a una altitud equivalente de 3.000 m. Esta técnica innovadora permitirá mejorar la productividad y el bienestar de los trabajadores a gran altitud.
International Journal of Occupational and Environmental Health, jul.-set. 1999, vol.5, n°3, p.187-193. Ilus. 23 ref.

1997

CIS 00-428 Patología en la altura
Esta publicación contiene una colección de artículos concernientes a los estudios realizados sobre diferentes patologías en altura, llevados a cabo en el hospital general de Chúlec, Perú, situado a 3.730 metros de altitud. Dichos estudios se clasifican bajo los siguientes títulos: pediatría, medicina general, cirugía, ginecología y obstetricia y medicina del trabajo. En este último, los estudios abarcan el trauma acústico, la fatiga auditiva y la prevalencia de casos de sordera de etiología profesional, la evaluación de la función visual de los trabajadores empleados en minas de metal y los niveles de intoxicación por arsénico en los trabajadores expuestos de una planta metalúrgica.
Oficina de Comunicaciones y RR.PP. de CENTROMIN PERÚ S.A., Perú, [1997]. 254p. Ilus. Ref.bibl.

CIS 97-2088 Sulaiman Z.M., Pilmanis A.A., O'Connor R.B.
Relación entre la edad y la sensibilidad a la enfermedad de descompresión debida a la altitud
Relationship between age and susceptibility to altitude decompression sickness [en inglés]
Se analizan los datos obtenidos de 1.299 experiencias de exposición a ciertas condiciones de vuelo, realizadas en cámaras de altitud entre 1983 y 1994. Las edades de los individuos oscilaban entre los 18 y 48 años. Según los resultados existía una tendencia al aumento de la sensibilidad a la enfermedad de descompresión en función de la edad, con especial incidencia en los sujetos mayores de 42 años.
Aviation, Space, and Environmental Medicine, ago. 1997, vol.68, n°8, p.695-698. Ilus. 15 ref.

CIS 97-1384 Loftin K.C., Conkin J., Powell M.R.
Modelización de los efectos del ejercicio físico durante la fase de preparación respiratoria con 100 % de oxígeno sobre el riesgo de enfermedad por descompresión hipobárica
Modeling the effects of exercise during 100% oxygen prebreathe on the risk of hypobaric decompression sickness [en inglés]
Se analizan los estudios relacionados con los efectos del ejercicio físico (realizado durante la fase de preoxigenación) sobre la incidencia de la enfermedad por descompresión hipobárica (EDH), y se ha desarrollado un modelo estadístico de previsión de la EDH. Se creó un modelo de probabilidad dosis-respuesta basado en el ratio presión claculada del nitrógeno sobre los tejidos - presión ambiental total, aplicable a dos casos: preoxigenación con ejercicio físico y en reposo. Los resultados muestran que el ejercicio físico durante la preoxigenación prácticamente dublicaba la difusión y la eliminación del nitrógeno en los tejidos, y disminuía considerablemente el riesgo de EDH. Este modelo constituye una útil herramienta de planificación para la elaboración de protocolos de preparación respiratoria y para la prevención de las EDH entre los astronautas.
Aviation, Space, and Environmental Medicine, mar. 1997, vol.68, n°3, p.199-204. 23 ref.

1996

CIS 98-1525 Gunga H.C., Röcker L., Behn C., Hilderbrandt W., Koralewski E., Rich I., Schobersberger W., Kirsch K.
Influencia del trabajo a turnos en los Andes chilenos ( 3.600 m) sobre la eritropoyetina y los mecanismos de adaptación al trabajo a gran altitud
Shift working in the Chilean Andes (>3600m) and its influence on erythropoietin and the low-pressure system [en inglés]
Temas tratados: Chile; fisiología de la sangre; gran altitud; hipoxia; tensión nerviosa; trabajo intermitente; trabajo a turnos.
Journal of Applied Physiology: Respiratory, Environmental and Exercise Physiology, 1996, vol.81, p.846-852. Ilus. 29 ref.

CIS 96-1015 Conkin J., Kumar V., Powell M.R., Foster P.P., Waligora J.M.
Modelo probabilista de la enfermedad de descompresión hipobara establecido en función de 66 ensayos en cámara experimental
A probabilistic model of hypobaric decompression sickness based on 66 chamber tests [en inglés]
Se describe una técnica para evaluar la probabilidad de la enfermedad de descompresión entre los astronautas que desempeñan actividades extravehiculares (AEV). Se analizaron los datos obtenidos en 66 ensayos en cámara hipobara (211 casos de enfermedad de descompresión en 1.075 exposiciones). Las variables consideradas eran la desnitrogenización previa a la descompresión, la magnitud de la descompresión, el ejercicio posterior a la descompresión y la duración de las AEV. Los modelos de probabilidad se ajustaron utilizando las técnicas del análisis de supervivencia. La probabilidad constante de enfermedad de la descompresión se describía mejor por la disminución tisular en función de la reducción de la presión ambiente tras la descompresión, conclusión avanzada por otros estudios.
Aviation, Space, and Environmental Medicine, feb. 1996, vol.67, n°2, p.176-183. 20 ref.

CIS 96-1018 Basu C.K., Selvamurthy W., Bhaumick G., Gautam R.K., Sawhney R.C.
Cambios respiratorios durante los primeros días de aclimatación a altitudes crecientes
Respiratory changes during initial days of acclimatization to increasing altitudes [en inglés]
Se controlaron diariamente los cambios respiratorios en 16 hombres a nivel del mar y a niveles de altitud de 3.110 m., 3.445 m. y 4.177 m., y en individuos de un grupo aclimatado que habían vivido a 3.110 m. y 4.177 m. durante dos años. Los valores de la función respiratoria se tabularon para cada altitud. La primera adaptación respiratoria se produjo al 3º día a 3.110 m. y se observó una disminución suplementaria a 4.117 m. con una variación cíclica el día 6º. Parece que la adaptación a la hipoxia en sujetos aclimatados difiere en función del nivel de altitud a 3.110 m o a 4.177 m.
Aviation, Space, and Environmental Medicine, ene. 1996, vol.67, n°1, p.40-45. Ilus. 31 ref.

1995

CIS 96-332 Exposición a radiaciones durante los vuelos a gran altitud
Radiation exposure and high-altitude flight [en inglés]
Este informe recoge los conocimientos actuales sobre los niveles de radiaciones ionizantes durante los vuelos a gran altitud, y el riesgo de cáncer debido a las radiaciones, así como los efectos sobre el desarrollo del embrión y del feto. Se incluyen comentarios sobre las dosis registradas a diferentes altitudes, los efectos biológicos, los límites de las estimaciones de los riesgos que se realizan en la actualidad, las evaluaciones de los riesgos para la tripulación y los pasajeros, y los aspectos filosóficos de la radioprotección, Para altitudes mayores, las dosis equivalentes recibidas son de dos a tres veces más elevadas que las que se reciben a las altitudes de los vuelos anteriormente. Se recomienda profundizar en la investigación sobre los niveles de exposición a las radiaciones, los efectos biológicos potenciales y la elaboración de líneas directrices que garanticen una protección adecuada.
National Council on radiation Protection and Measurements, 7910 Woodmont Avenue, Bethesda, MD 20814-3095, USA, jul. 1995. v, 25p. Ilus. 38 ref. Precio: USD 15,00.

CIS 95-2300 Ward M.P., Milledge J.S., West J.B.
Medicina y fisiología de las altitudes elevadas
High altitude medicine and physiology [en inglés]
En el sumario de este manual: respuesta humana a la altitud; respuesta ventilatoria a la hipoxia y al anhídrido carbónico; difusión pulmonar; sistema cardiovascular; hematología; trnasporte de gases por la sangre; tejidos periféricos; ejercicio; factores que limitan el rendimiento en altitudes extremas; sueño; nutrición y función intestinal; sistemas endocrinos y renal; sistema nervioso central; poblaciones de altitudes elevadas; mal de montaña; edema de pulmón, edema cerebral y hemorragia retiniana en las grandes altitudes; alteraciones musculares; equilibrio térmico y termorregulación; reacciones ante el frío; hipotermia; lesiones locales causadas por el frío; accidentes, urgencias quirúrgicas y anestesia; accidentes de esquí y salvamento en la montaña; accidentes producidos por el calor y la radiación solar; condición física de grandes altitudes - ocio y actividades comerciales; forma y rendimiento en la montaña; aspectos prácticos de los estudios de campo.
Chapman & Hall, 2-6 Boundary Row, London SE1 8HN, Reino Unido, 2^a ed., 1995. xviii, 618p. Ilus. Ref.bibl. Indice. Precio: GBP 69,00.

1994

CIS 94-2085 Kumar K.V., Powell M.R.
Survivorship models for estimating the risk of decompression sickness
The applicability of survival analysis for modelling the risk of decompression sickness (DCS) is illustrated by using data from earlier studies of hypobaric chamber exposures. A method for estimating the overall incidence-free survival rates for circulating microbubbles, symptoms and test aborts is described and the results are discussed. Survival analysis is shown to have certain advantages over other methods for modelling the risk of DCS.
Aviation, Space, and Environmental Medicine, July 1994, Vol.65, No.7, p.661-665. 15 ref.

1992

CIS 93-1352 Rudge F.W.
The role of ground level oxygen in the treatment of altitude chamber decompression sickness
Data were collected on the use of ground-level oxygen in the treatment of altitude chamber decompression sickness among US Air Force personnel during 1989-91. Data included age, sex, time of symptom development, type of initial treatment and response to ground-level oxygen administration. Of the 175 cases treated with ground-level oxygen, 40 failed to resolve and were treated with compression therapy. The remaining 135 all resolved with ground-level oxygen, obviating the need for hyperbaric oxygenation. Factors associated with a favourable response to this type of treatment are discussed.
Aviation, Space, and Environmental Medicine, Dec. 1992, Vol.63, No.12, p.1102-1105. 12 ref.

CIS 93-1042 Kumar K.V., Waligora J.M., Gilbert J.H.
The influence of prior exercise at anaerobic threshold on decompression sickness
In a study to examine the effects of exercise prior to decompression on the incidence of altitude decompression sickness (DCS), 39 subjects exercised at their predetermined anaerobic threshold levels for 30min each day for three days prior to exposure to an altitude of 6,400m in a hypobaric chamber. No significant difference in DCS preferences was found.
Aviation, Space, and Environmental Medicine, Oct. 1992, Vol.63, No.10, p.899-904. 26 ref.

CIS 93-305 Crowley J.S., Wesensten N., Kamimori G., Devine J., Iwanyk E., Balkin T.
Effect of high terrestrial altitude and supplemental oxygen on human performance and mood
In a study to investigate the effects of high terrestrial altitude on human performance, 13 male soldiers ascended in 10min from sea level to 4,300m (simulated) and remained there for two and a half days. Subjects carried out cognitive tests and mood tests and completed a questionnaire to assess the severity of acute mountain sickness (AMS) symptoms. Following rapid ascent, performance was most affected during the first eight hours. Recovery of cognitive function was slower in subjects suffering from AMS.
Aviation, Space, and Environmental Medicine, Aug. 1992, Vol.63, No.8, p.696-701. 26 ref.

1991

CIS 92-1012 Seigneuric A.
Pathology associated with altitude and flights in the atmosphere and in space
Pathologie liée à l'altitude et aux vols dans l'atmosphère et dans l'espace [en francés]
Following a summary of the hazards associated with high altitude (oxygen rarefaction and hypoxia, cold, humidity and radiation), acute pathological effects are examined: mountain sickness, acute pulmonary oedema, cerebral oedema and vascular complications, particularly in the retina. Effects of a prolonged stay at altitude, which may result in either a satisfactory adaptation or Monge disease, are also outlined. The effects of flights in the atmosphere and in space are dependent on the duration and altitude of the flight and require the protective measures described.
Encyclopédie médico-chirurgicale, Toxicologie-Pathologie professionnelle, 1991. 10p. 77 réf.

CIS 92-300 Butler F.K.
Decompression sickness presenting as optic neuropathy
Report of a case of acute optic nerve dysfunction seen in a parachutist after repeated hypobaric exposures. The patient made 2 to 4 high altitude exposures per day for 4 days in an unpressurised aircraft at a maximum altitude of 3,636-3,939m. Resultant symptoms included persistent headache, paracentral scotoma and decreased visual acuity in the left eye. Symptoms improved promptly following treatment with recompression and hyperbaric oxygen therapy. This is believed to be the first case of decompression sickness presenting as optic neuropathy.
Aviation, Space, and Environmental Medicine, Apr. 1991, Vol.62, No.4, p.346-350. Illus. 11 ref.

CIS 92-298 Rush W.L., Wirjosemito S.A.
Decompression sickness: Risk factors and the monoplace chamber - A case report
This case report of serious decompression sickness (DCS) with pulmonary and neurological manifestations illustrates the principles and concerns related to the use of monoplace chambers for the treatment of DCS. Closely timed recurrent altitude exposure is discussed as a risk factor for DCS, and a newly defined risk factor associated with the menstrual phase is considered relevant to this case. It is recommended that arrangements be made early in the management of DCS cases for transfer to a chamber which can provide definitive therapy.
Aviation, Space, and Environmental Medicine, May 1991, Vol.62, No.5, p.414-417. 19 ref.

1990

CIS 92-297 Rudge F.W.
Relationship of menstrual history to altitude chamber decompression sickness
Records at the USAF School of Aerospace Medicine were reviewed to determine the relationship between the incidence of altitude chamber decompression sickness (DCS) in females and menstrual history. A significant inverse linear correlation was noted between the number of days since the start of the last menstrual period and the incidence of DCS. The underlying mechanism for the correlation between menstrual cycle and susceptibility to development of DCS is unknown. It is concluded that women are at higher risk of developing altitude related DCS during menses, with the risk decreasing linearly as the time since last menstrual period increases.
Aviation, Space, and Environmental Medicine, July 1990, Vol.61, No.7, p.657-659. Illus. 7 ref.

CIS 91-296 Devine J.A., Forte V.A., Rock P.B., Cymerman A.
The use of typanometry to detect aerotitis media in hypobaric chamber operations
Diagnosis and quantification of aerotitis media were performed using a modified commercially-available tympanometer under hypobaric conditions. Subjects were 22 males and 9 females, 22-43 years of age, who were tested in each ear with the tympanometer prior to and after exposure, sequentially at the barometric pressue plateaus of 706, 656, 609, 586, 564, and 522mm Hg, and following an induced ear block during a 1-min descent from 522 to 586mm Hg. Each subject was examined once either alone or in pairs during a 90-min exposure. Aerotitis media was detected using tympanometry at simulated altitude as evidenced by the difference between measurements made during induced ear blocks and those made prior to inducement, as well as following relief of the pressure differential with the Valsolva manoeuvre. There were no significant differences between pre- and post-induced aerotitis media values at 586mm Hg, or between pre- and post-hypobaria. Thus, tympanometry can be a valuable tool in managing aerotitis media in the aeromedical environment.
Aviation, Space, and Environmental Medicine, Mar. 1990, Vol.61, No.3, p.251-255. Illus. 20 ref.

1989

CIS 91-1493 Los riesgos del trabajo en la alta montaña
Training manual. Contents: jobs at high altitudes; the Cordillera environment (high winds; action of water, snow and ice; reduced air pressure); proper work practices (establishing camp; selection of personnel; construction of camps; safety organisation); dangers of transport at high altitudes; work in cold environments; protection against avalanches; emergency planning.
Asociación Chilena de Seguridad, Casilla 14565, Correo Central, Santiago, Chile, Sep. 1989. 33p. Illus.

1988

CIS 90-2082 Mekjavic I.B., Banister E.W., Morrison J.B.
Environmental ergonomics: sustaining human performance in harsh environments
This book containing a selection of papers presented at the 2nd International Environmental Ergonomics Conference, held at Whistler, British Colombia (Canada), on 21-25 July 1986 offers a collaborative approach to the study of human performance in the face of harsh environments such as equatorial and polar regions, ocean floors and outer space, where hot, cold, wet, high- and low- pressure and other extreme conditions affect the body's physiological and cognitive functions to a significant degree.
Taylor and Francis Ltd., Rankine Road, Basingstoke Hants RG24 OPR, United Kingdom, 1988. 412p. Illus. Bibl. Index. Price: GBP 39.00.

1986

CIS 86-1967 Vogel H.
Diseases due to differences in environmental pressure
Maladies dues à des variations de la pression ambiante [en francés]
The 2 parts of this very detailed document present the following subjects: physical principles and laws; sources of risk (diving, high-pressure environments, high altitudes); pathogenesis and clinical tables (barotrauma, effects of gases dissolved in the body under increased pressure, gas bubbles in blood and body tissue during a rapid fall in air pressure, effects of oxygen deprivation, deaths during diving); medical and therapeutic prevention; insurance law; accident rates; legal case studies.
Caisse nationale suisse d'assurance en cas d'accidents, case postale, 6002 Luzern, Switzerland, Sep. 1986, n°8, 2 parts, 139p. Illus. 37 ref.

1982

CIS 84-1131 Kolesari G.L., Kindwall E.P.
Survival following accidental decompression to an altitude greater than 74,000 feet (22,555m)
The accident occurred in an industrial vacuum chamber. The victim experienced burst lung, massive decompression sickness, and sustained ebulism (vaporisation of blood). He remained "at altitude" for as much as 3-5min. He was still profoundly unconscious 5.5h after the accident. After treatment in a hyperbaric chamber with recompression he eventually recovered. Substantial barotrauma to the tissues was present. This is probably the most severe case of unprotected human decompression with survival reported to date.
Aviation, Space, and Environmental Medicine, Dec. 1982, Vol.53, No.12, p.1211-1214. Illus. 3 ref.

1981

CIS 82-1999 Mielle F.
Work at high altitudes and underground or underwater: Clinical physiopathology and practical deductions
Altitude et profondeur: physiopathologie clinique et déductions pratiques [en francés]
Physiological and pathological effects of altitude: hypoxia, physical factors, dynamic conditions, space flight; major pathological syndromes due to altitude. Contraindications (flight crews; periods spent at high altitudes). Physiopathology of underground work: minework, speleology. General considerations on hyperbaric physiopathology (physiology, decompression tables). Free diving, compressed-air and compressed-gas diving. Basic information on treatment of diving accidents. Contraindications for diving.
Cahiers de médecine interprofessionnelle, 4th quarter 1981, Vol.21, No.84, p.25-63. Illus. 45 ref.

CIS 81-1482 Colin J.
Physiopathology of high altitudes and atmospheric and space flights
Physiopathologie liée à l'altitude et aux vols dans l'atmosphère et l'espace. [en francés]
Revised text of an article. The 1st part deals with: high-altitude hypoxia (effects and tolerance) and high altitude pathology (barotraumatic effects, aviation decompression syndrome, ebullism, prevention of high-altitude risks). The 2nd part covers: the physiopathology of acceleration (haemodynamic effects of prolonged acceleration, mechanical effects of short-term acceleration and the effects of acceleration on spatial orientation, posture and movement mechanisms). The 3rd part examines the three main mechanisms behind physiopathological reactions to weightlessness, and their prevention.
Encyclopédie médico-chirurgicale, maladies et agents physiques, 18 rue Séguier, 75006 Paris, France, 1981. 16p. 30 ref.

1980

CIS 82-1823 Prevention of furnace implosions in multiple burner boiler-furnaces
This standard, adopted as an American National Standard 28 July 1980, establishes minimum standards for the design, installation and operation of boiler-furnaces, their fuel burning, air supply and combustion products removal systems, which include induced-draught fans and related control equipment, to prevent furnace implosions. It offers 2 methods for minimising the risk of negative furnace draught in excess of furnace structural capability: design of the furnace and flue gas removal system so that the low gas flow maximum head capability of the induced-draught fan system with ambient air does not exceed the design pressure of furnace ducts and associated equipment; or provision of a furnace pressure control system, draught fan directional blocking, or run-backs. Contents: equipment requirements (furnace structural design; combustion products removal; furnace pressure control system); sequence of operations; functional and system requirements for interlock and alarm systems.
National Fire Protection Association, Batterymarch Park, Quincy, MA 02269, USA, 1980. 18p. Illus. Price: US-$5.00.

1978

CIS 79-41 Kryger M., Aldrich F., Reeves J.T., Grover R.F.
Diagnosis of airflow obstruction at high altitude.
Many workers in the US mining industry work at high altitudes (>3,000m). A large molybdenum (hard rock) mine in Colorado (altitude 3,100m) instituted respiratory screening of all newly hired and current employees in 1976. Evaluations included a respiratory questionnaire, spirometry, and a chest X-ray. The authors evaluated all men screened between March 1976 and April 1977 (approximately 1,600 subjects) and then excluded all subjects who had smoked cigarettes, who had a history of lung disease, or whose present or previous job was in an environment of mineral dusts or chemical fumes, leaving 126 nonsmokers believed to be free of lung disease. The authors conclude from the results of measurements (FVC; FEV₁; FEV₁/FVC, mean forced expiratory flow) that using predicted sea level values for spirometry done at high altitude, underestimation of airway obstruction may result, and established spirometric normal values for an altitude of 3,100m for white men.
American Review of Respiratory Disease, June 1978, Vol.118, No.6, p.1055-1058. Illus. 14 ref.

1977

CIS 78-1180 Mambetaliev B.
Indices for evaluation of working capacity of miners according to altitude
Nekotorye pokazateli rabotosposobnosti u gornorabočih na različnyh vysotah [en ruso]
Results of ergometric and other studies in 44 and 43 miners working respectively at low (860m) and high altitudes (2,800m) in the Tsian'-Shan mountains (USSR). Maximal aerobic power was relatively poor in the high-altitude workers. Studies of functional parameters of mental stress caused by arduous work in difficult climatic conditions showed the cardiovascular and respiratory systems of high-altitude miners to be under very much greater stress than in those working at low altitudes. These differences must be taken into account when organising mining work on a scientific basis.
Gigiena i sanitarija, Aug. 1977, No.8, p.35-40. 14 ref.

1976

CIS 78-1135 Böni M., Schibli R., Nussberger P., Bühlmann A.A.
Diving at diminished atmospheric pressure: Air decompression tables for different altitudes.
The rationale of the tables and the studies that led up to them (106 simulated dives and 278 actual dives at 900-1,700m altitude) are described. The schedules themselves are decompression tables, maximum ascent-rate tables, surface-interval tables and repetitive timetables, for altitudes up to 3,200. Schedules up to 2,000m were tested in humans under wet conditions; some are untested.
Undersea Biomedical Research, Sep. 1976, Vol.3, No.3, p.189-204. 5 ref.

CIS 76-1259 Treaftis H.N., Tomb T.F., Carden H.F.
Effect of altitude on personal respirable dust sampler calibration.
Studies on the effect of altitude on 3 personal samplers (MSA Model G, Bendix 3900 and Bendix C115) performed in a vacuum chamber simulating altitudes of 800-16,000 feet (240-4,800m) are described. Pump performance and calibration of the flow-rate meters were both affected by altitude changes. In all 3 cases, the flow rate of a pump unit calibrated for 2l/min at 800 feet increased by approx. 5% at 12,000 feet if not adjusted. If at 12,000 feet the flow was adjusted so that the flow-rate meter float was at the original calibration mark, flow rate increased by 10-23%. Equations for the empirical relations so derived are given for each sampler.
American Industrial Hygiene Association Journal, Mar. 1976, Vol.37, No.3, p.133-138. Illus. 6 ref.

1974

CIS 75-776 Thierfeldt P.
Risks of traumatic incidents in simulated low-pressure ascents in decompression chamber, their prevention and treatment
Zwischenfälle bei Unterdruckkammeraufstiegen, deren Vorbeugung und Behandlung [en alemán]
The author considers the possibilities of decompression-chamber accidents due to lack of oxygen, low pressure or variations in air pressure. Barotrauma of ear and nasal sinuses, observed in 10% of the cases examined, is the most frequent accident, followed by pre-collapse and collapse due to hypoxia, decompression disturbances and altitude meteorism at heights between 10,000 and 12,000m. Reference is made to the possibility of aero-odontalgia, hypocapnia and vomiting into the respirator. Prevention and treatment. Importance of psychological aspects when conducting simulated ascent tests and necessity for employing experienced personnel for this purpose.
Verkehrsmedizin und ihre Grenzgebiete, 1974, Vol.21, No.7, p.230-236.

1973

CIS 75-878 Ringenbach G.
Haematological adjustment to high altitudes
L'acclimatation hématologique à l'altitude. [en francés]
After a review of past and current knowledge concerning altitude polyglobulia or long-term polyglobulia, that is, the true haematological adjustment to altitude, the author summarises 20 years of personal research on the phenomena which lead to this adaptation. He used a veino-capillary coupled erythrogram technique on 72 subjects who had to remain for long periods at high altitudes on account of their occupation. He observed a reduction of red blood cells in the venous blood, and an unequal distribution of these cells in both venous blood and capillary blood. Based on these observations, he derived a chronology of adaptation and conducted a pathogenic study from which he concluded that there was pertubation of the water metabolism. He suggests prophylaxis by administration of haematoporphyrin to enable workers to live safely and comfortably at high altitudes.
Revue de médecine aéronautique et spatiale, 4th quarter 1973, Vol.12, No.48, p.595-600. 19 ref.