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In Earth's atmosphere, carbon dioxide is a trace gas that plays an integral part in the greenhouse effect, carbon cycle, photosynthesis and oceanic carbon cycle. It is one of three main greenhouse gases in the atmosphere of Earth. Water vapor is the primary greenhouse gas, as of 2010, contributing 50% of the greenhouse effect, followed by ...
On average, exposures at 100 ppm or greater is dangerous to human health. [23] The WHO recommended levels of indoor CO exposure in 24 hours is 4 mg/m 3. [24] Acute exposure should not exceed 10 mg/m 3 in 8 hours, 35 mg/m 3 in one hour and 100 mg/m 3 in 15 minutes. [25]
The pCO 2 of Earth's atmosphere has risen from approximately 280 ppm (parts-per-million) to a mean 2019 value of 409.8 ppm as a result of anthropogenic release of carbon dioxide from fossil fuel burning. This is the highest atmospheric concentration to have existed on Earth for at least the last 800,000 years. [1]
It is calculated using the LD50 or LC50. [ 1 ] The Occupational Safety and Health Administration (OSHA) regulation (1910.134 (b)) defines the term as "an atmosphere that poses an immediate threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to escape from a dangerous atmosphere."
An air quality index (AQI) is an indicator developed by government agencies [ 1 ] to communicate to the public how polluted the air currently is or how polluted it is forecast to become. [ 2 ][ 3 ] As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with respiratory ...
Carbon dioxide concentrations in closed or confined rooms can increase to 1,000 ppm within 45 minutes of enclosure. For example, in a 3.5-by-4-metre (11 ft × 13 ft) sized office, atmospheric carbon dioxide increased from 500 ppm to over 1,000 ppm within 45 minutes of ventilation cessation and closure of windows and doors.
This is an accepted version of this page This is the latest accepted revision, reviewed on 9 October 2024. Gas in an atmosphere with certain absorption characteristics This article is about the physical properties of greenhouse gases. For how human activities are adding to greenhouse gases, see Greenhouse gas emissions. Greenhouse gases trap some of the heat that results when sunlight heats ...
e. Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. [ 1 ] It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological ...