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УДК: 614.4, 614.894.3 DOI:10.33920/med-08-2101-03

An impact of increased concentration of carbon dioxide in the inhaled air while using respirators by medical workers

Kaptsov Valerii Aleksandrovich PhD in Medicine, Professor, Member of the Academy of Sciences, Head of the Occupational Hygiene Department, State Unitary Enterprise «All-Russian Research Institute of Railway Hygiene» of Rospotrebnadzor; 125438 Russia, Moscow, Pakgauznoe sh., 1, bldg. one; e-mail: kapcovva39@mail.ru, http://orcid.org/0000-0002-3130-2592

The morbidity of infectious diseases among medical workers is higher than among the popula- tion. Improving the protection of workers from the inhalation of bioaerosols will reduce the risk of their ill- ness. The goal is to establish how and to what extent using the personal respiratory protective equipment (RPE) impairs gas exchange during breathing, preventing its from achieving its timely and correct using in a polluted atmosphere. Available publications of NIOSH, Taylor & Francis press publications, Oxford University Press and other sources are being used. It has been found that prolonged using a respirator increases the «dead space», decreasing the oxygen concentration and increasing the concentration of carbon dioxide in the inhaled air. The substance of carbon dioxide while using RPE (without air supply) can be many times higher than the maximum permissible concentration (MPC in the air of the working area). The degree of excess depends on the type of the RPE and air consumption by the worker; while doing light work, the excess increases. The requirements for the RPEs, presented during their certification, relate only to the case of a high air flow rate when performing hard work, and their implementation does not allow adequately assessing the negative impact on the worker during prolonged using a respirator. An excessive carbon dioxide substance in a combination of a low oxygen content in the inhaled air, discomfort and skin irritation complicates the use of RPE and can lead to temporary disability.

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Statistics data shows that among medical workers the morbidity of diseases that can be transmitted by airborne droplets is significantly higher than among the population [1]. An urgent task is an improving the protection of medical workers from infection, including the inhalation of bioaerosols.

Various methods can be used to protect against harmful production factors: an elimination or weakening at the source itself; using the collective protection means; organizational and medical-preventive measures; as well as personal protective equipment (PPE) — are listed in order of decreasing effectiveness [2].

A protection of doctors in contact with infected patients without using a respiratory protective equipment is difficult. However, with any degree of reduction of the content of harmful substances in the inhaled air, provided by a respirator, ignoring its use in a polluted atmosphere sharply increases the exposure dose. For example, with a constant concentration of contaminants, using a respiratory protective equipment (RPE) for only 5 % of the time will reduce their exposure by more than 20 times, regardless of the type of the RPE [3]. Hours-long daily use of respirators in health-care institutions during influenza epidemics has shown that it is very difficult to ensure continuous and timely use of the RPE. Identification of the causes preventing the use of the RPE can help find ways to facilitate its use by workers, reduce the morbidity of diseases among doctors and improve the quality of medical care for the population.

The goal is to assess the effect of increased concentration of carbon dioxide in the inhaled air during prolonged using the RPE by medical workers to develop possible ways to improve the protection of doctors from the inhalation intake of bioaerosols.

We have used available information of the use of the RPE in industry and health-care institutions, as well as its research, published by Oxford University Press, Taylor & Francis and other available publications.

Для Цитирования:
Kaptsov Valerii Aleksandrovich, An impact of increased concentration of carbon dioxide in the inhaled air while using respirators by medical workers. Санитарный врач. 2021;1.
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