What Are Airborne Particles?

Air microorganisms are microorganisms that exist in the air. Air microorganisms are the main air plankton, and they are resistant to drier environments and ultraviolet rays. They mainly include cocci (aerobic bacteria including hydras) attached to the dust and flying from the ground. Spores are aerobic bacilli (such as Bacillus subtilis), wild yeasts such as Selenium sp., And mold spores such as Penicillium. It also appears to be present in lower algae.

The types and numbers of microorganisms in the air vary with environmental conditions such as region, altitude, season, and climate. Generally, the microbe content is highest in the air of barns, public places, hospitals, dormitories, and urban streets, and in the air over the oceans, mountains, high altitudes, forests, grasslands, fields, snow-covered mountains or the air over the polar regions. Content is very small; due to the natural sedimentation of dust, the content of microorganisms is higher in the air close to the ground; when the ground is covered with snow and ice in winter, there are few microorganisms in the air. In windy and dry seasons, there are more microorganisms in the air and rain There are few microorganisms in the rear air. Air microorganisms are microorganisms that exist in the air. Air microorganisms are the main air plankton, and they are resistant to drier environments and ultraviolet rays. They mainly include cocci (aerobic bacteria including hydras) attached to the dust and flying from the ground. Spores are aerobic bacilli (such as Bacillus subtilis), wild yeasts such as Selenium sp., And mold spores such as Penicillium. It also appears to be present in lower algae. Microbes in humans, animals and plants, and soil can be dispersed in the air by droplets or dust, etc.

Generally, no pathogenic microorganisms exist in the air, but aerosols with pathogenic microorganisms are often suspended in the air near hospitals, veterinary hospitals, and livestock and poultry houses. Healthy people or animals are often infected by inhalation, which are called droplet transmission. And dust transmission, collectively known as airborne. ^[1]

Air contaminated with pathogenic microorganisms can often become a source or vector of pollution, causing epidemic diseases. Therefore, carrying out a bacteriological examination of the air to determine the nature and extent of air pollution by bacteria is of great significance for the prevention and control of infectious diseases and the hygienic supervision and protection of the environment. The pathogenic bacteria and other pathogenic microorganisms polluted in the air are many but small in number. It is difficult or impossible to detect one by one. Some pathogenic microorganisms require complicated equipment and conditions. Therefore, the total number of bacteria and the number of coliform bacteria are often used as bacteria. Science indicators. The total bacterial count refers to the total number of bacterial colonies generated on a solid medium under a certain condition by the unit mass (g), volume (mL), surface area (cm ² ) or volume (m ³ ) of the test sample. It only reflects the total number of a group of mesophilic, aerobic and facultative anaerobic bacteria colonies grown in ordinary nutrient agar. It is often used as an indicator of the degree of contamination of the test sample, and is used for soil, water, air and food hygiene. The basis of academic evaluation. ^[1]