Outdoor air pollution, in the most extreme cases, can be immediately identified even without any special training. It casts a haze over cities, collects on streets and buildings, and provides dramatic fodder for the news. But while high drama is often a prerequisite for news about air quality to be reported, the real story is the health impacts that occur even when the air isn't thick enough to see.
According to the EPA, Americans, on average, spend approximately 90 percent of their time indoors, where the concentrations of some pollutants are often 2 to 5 times higher than typical outdoor concentrations. Most pollutants affecting indoor air quality come from sources inside buildings, although some originate outdoors. Typical pollutants of concern include combustion products such as carbon monoxide, particulate matter, and environmental tobacco smoke; substances of natural origin such as radon; biological agents such as molds; pesticides; lead; asbestos; ozone (from some air cleaners); and various volatile organic compounds from a variety of products and materials
This is even more striking when the health eﬀects attributed to outdoor ﬁne particulate matter (PM2.5) rank among the risk factors with the highest health impacts in the world, annually accounting for over 3.2 million premature deaths. In October 2013, the World Health Organization announced they are considering particulate matter, a major component of indoor and outdoor air pollution, as a Group 1 carcinogen along with tobacco smoke and asbestos.
U.S. EPA Standards and Test Methods
National Ambient Air Quality Standards (NAAQS)
Section 109 of the Clean Air Act directs the Environmental Protection Agency (EPA) to establish National Ambient Air Quality Standards (NAAQS) requisite to protect public health with an adequate margin of safety (primary standard) and for the protection of public welfare (secondary standard). Section 109(d)(1) of the CAA requires EPA to complete a thorough review of the NAAQS at 5-year intervals and promulgate new standards when appropriate.
Complete details of the standards, measurement principles, and data interpreation, can be found in Title 40 of the Code of Federal Regulations Part 50
EPA Test Methods
EPA approved instruments are designated as either a Federal Reference Method (FRM) or Federal Equivalent Methods (FEM). The complete list of approved instruments for NAAQS evaluating is provided on the EPA Ambient Monitoring Technology Information Center (AMTIC) web site
Real Time Data
EPA and its State and Tribal partners publish near real-time air quality data (typically hourly updates) as well air quality forecasts on the AirNow web site.
The AirNow site also contains, links to Visibility Cameras, which are yet another way to evaluate air pollution.
Examples of clear and hazy days from Boston HazeCam:
Historical air quality test results are freely available through EPA AirData
EPA & Citizen Science Next Generation of Monitors
EPA has also been involved with Next Generation Air Measuring and is currently offering its Citizen Science Toolbox Resources online:
- Air Sensor Guidebook;
- Air Sensor Technology: State of the Science Presentation;
- Mobile Sensors and Applications for Air Pollutants; and
- Sensor Evaluation Report.
Other Resources for Air Quality Standards
The U.S. Center for Disease Control (CDC) and its National Institute for Occupational Safety and Health (NIOSH) also offer a wealth of guidance. In particular, the NIOSH Manual of Analytical Methods is a collection of procedures for sampling and analysis of contaminants including workplace air.
The Agency for Toxic Substances and Disease Registry (ATSDR), based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services. Their Toxicological Profiles, is particularly useful for when a pollutant can be identified by compound or element.
Particle Sensing Project
Public Lab has initiated a Particle Sensing Project focused primarily on Silica. This project overlaps with and includes the DustDuino and is coordinated on the Air-Quality Google Group (join in left sidebar).
DustDuino can help individuals with limited resources monitor PM10 and PM2.5 concentrations, indoors or outdoors. It uses Shinyei PPD42NS, a $15USD optical sensor that uses an LED and a lens to determine the concentration of dust in a partially closed chamber that draws in air from its surroundings. The sensor data is received by an Arduino development board and transmitted to Xively. Prototypes of DustDuino have been successfully built and used in various indoor and outdoor locations.
Cypress Hills Air Quality (CHAQ) Initiative
In 2013, this 8 week Air Quality Class was created for middle-schoolers in the Cypress Hills Air Quality (CHAQ) Initiative, with support from the United States Environmental Protection Agency's program "Citizen Science: Community Involvement Today and in the Future". This project was a collaboration with the Cypress Hills Local Development Corporation. Joe Saavedra and Liz Barry are the Public Laboratory facilitators. Georgia Bullen, Yael, and Jason Lipshin are involved from MIT.
Air Column Monitor
The air column monitor is in early phases of development. The April 2012 EcoHackII at Parsons in NYC brought together a group of developers, "scientists", data visualizers and activists to work on the initial design. This tool is being developed as a partnership between Public Lab and the AirQualityEgg/Sensemakers community.
Roomba Indoor Air Quality Mapping
This tool is being developed to experiment with visually mapping indoor air quality. A Roomba--the room cleaning vacuum--is programmed to travel all around a room once it is left to roam. Therefore, it is an ideal tool to assess the quality of air throughout a room.