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At least 487 records · Page 27Linked to original sources
PubMed1981

Nitrous oxide levels during retinal cryosurgery.

Nitrous oxide levels were monitored before, during, and after retinal cryotherapy. These units produced an average elevation of the nitrous oxide concentration in the operating room to the level of 963 ppm. Nitrous oxide levels in a control operating room using general endotracheal anesthesia with nitrous oxide ranged from 75 to 200 ppm. Nitrous oxide has been reported to be associated with various teratogenic effects in experimental animals and may be associated with other human ailments. The use of a scavenger system specifically designed to handle the exhaust from ophthalmic nitrous oxide units can reduce the nitrous oxide concentration by 50% or more and is, therefore, recommended.

Cryosurgery↗
PubMed1991

A suggested air standard for lead to protect the public during lead abatement activities.

Lead abatement is developing as a new industry in a manner similar to asbestos abatement. Recent standards and guidelines have been established by various governmental agencies to ensure worker and public protection during lead abatement. An air concentration standard of 3.0 ug/m3 for lead is suggested in non-work locations based on hypothetical body burden calculations and sampling results during lead abatement activities. Adverse health effects to the general public resulting from exposure to lead from abatement activities at this concentration should not be observed.

Air Pollutants↗
PubMed1983

Ethylene oxide dispersion from gas sterilizers.

Ethylene oxide (EtO) is widely used by the health industry for sterilizing heat-sensitive devices. About 100 000 workers are regularly exposed to this chemical, used in an estimated 10 000 sterilizing units in U.S. health care facilities. Based on recent findings. NIOSh has recommended that EtO be regarded as a potential carcinogen and has urged OSHA to reexamine its present standard of 50 ppm. The ACGIH Notice of Intended Changes for 1982 has proposed reducing the recommended limit from 10 ppm TWA to 1 ppm and considers EtO a suspect carcinogen for man. Because of this increasing concern for its toxicity, it is imperative that the exposures to EtO be assessed, and that all reasonable steps to reduce these exposures be taken. This study demonstrates the effects of local exhaust ventilation, sterilizer chamber temperature, and sterilizer relative humidity in relation to their influence on EtO plume directionality, concentration and duration. Using two Foxboro/Wilks Miran 1A General Purpose Gas Analyzers, EtO concentrations were simultaneously monitored both immediately above and below the sterilizer door during various process runs, at three different types of sterilizers. Sterilizer operating conditions were representative of temperatures (38-54 degrees C (100-130 degrees F)), and relative humidities (30-50%) commonly employed in the sterilization process. The effects of varying local exhaust parameters were observed. Results clearly demonstrated that EtO tends to flow upward when the sterilizer door is opened. In all cases, the highest concentrations were observed at the upper location. Local exhaust ventilation significantly reduced the concentration of EtO observed and lessened the duration for which these levels persisted. Changes in temperature and relative humidity, within the range cited, have not shown any significant differences in EtO evolution patterns, concentrations or duration.

Ethylene Oxide↗
PubMed1989

Effect of respiratory protective equipment on exposure to asbestos fibres during removal of asbestos insulation.

Asbestos concentrations were measured within powered respirators used by workers involved in the removal of asbestos-containing insulation. Fibre concentrations within the protective gear appeared to be above the Dutch threshold limit value for crocidolite (0.2 f cm-3). Possible sources of exposure were analysed and measures were taken to improve the situation. After this, the fibre concentrations in the breathing area were reduced and were below the Dutch concentration limit.

Air Pollutants, Occupational↗