What Does Ambient Air Mean?
Ambient air refers to atmospheric air in its natural state.
Ambient air typically consists of 78% nitrogen and 21% oxygen. The remaining 1% is a combination of carbon, helium, methane, argon, and hydrogen. The closer the air is to sea level, the higher the percentage of oxygen.
Safeopedia Explains Ambient Air
Industrial operations, vehicles, and volcanoes emit potentially harmful pollutants that affect a region’s air quality. Fine particulate matter released from the combustion of fuel affects human health the most. The World Health Organization (WHO) estimates that ambient air pollution accounts for about 4.2 million deaths per year due to heart disease, stroke, chronic respiratory diseases, and lung cancer.
Pollutants in ambient air are measured using instruments with advanced technology for critical regulatory parameters, like particulate matter (PM)10 and PM2.5 mass concentration. Instruments for monitoring dust and aerosols use methods such as gravimetric sampling, light scattering, and beta attenuation. Instruments are also available for measuring the presence of toxic vapors and gasses in the ambient air.
These measurements are important, since unchecked exposure can lead to chronic and serious health and respiratory complications.
The Occupational Safety and Health Administration (OSHA) conducts regular inspections by sending quality control agents to check for chemical hazards at the workplace. One goal of these inspections is to ensure that the ambient air’s contaminant levels do not exceed limits established by regulatory bodies, including:
- Recommended exposure limit (REL)
- Threshold limit values (TLVs)
- Workplace environmental exposure levels (WEELs)
The Environmental Protection Agency (EPA) lists additional reasons to monitor ambient air:
- Providing the general public with timely air pollution data
- Providing information on air quality trends
- Setting goals and standards for air quality
- Assessing the effectiveness of emissions control strategies
- Providing data for research on the health effects of pollution
Programs for Ambient Air Quality Monitoring
Under the Clean Air Act, the EPA is tasked with setting National Ambient Air Quality Standards (NAAQS) for six common air pollutants found across the country that are harmful to health and the environment:
In India, the Central Pollution Control Board implemented the National Air Quality Monitoring Programme (NAMP) with the aim of:
- Identifying violation of prescribed air quality standards
- Identifying non-attainment cities
- Developing preventive and corrective measures
- Understanding the environment's natural pollution cleansing processes (e.g. dispersion, precipitation, dry deposition)
The program targets four pollutants for regular monitoring:
- Sulfur dioxide (SO2)
- Nitrogen oxides
- Respirable suspended particulate matter (RSPM/PM10)
- Fine particulate matter (PM2.5)
On a global scale, the WHO has created the Global Platform on Air Quality and Health
in collaboration with 50 other regional and international agencies and research institutions. The goal of this initiative is to strengthen the capacity for monitoring air quality worldwide and to assess and report the adverse health effects of bad air quality. It also promotes the implementation of policies that reduce exposure to air pollution.