What is carbon monoxide? How is it produced? Common sources of carbon monoxide Sources of carbon monoxide in the home environment can include fuel-burning devices such as: boilers, furnaces, water heaters, fireplaces, charcoal grills, gas and kerosene heaters, gas and wood stoves and clothes dryers.
CO2 is a gas used in carbonated drinks and is also the same gas breathed out by humans. CO poisoning is not caused by faulty appliances, but by lack of air movement.
For example, a gas boiler may be operating properly but if the flue is blocked or defective, CO can vent into your home and kill you. Many people believe that carbon monoxide is not a big problem. Because of the local nature of high-CO episodes, extensive modeling of the entire urban airshed may be unnecessary for CO-attainment demonstrations.
Highly trained personnel are needed to conduct the simulations. However, a simplified approach of this method may be appropriate in some cases. More complicated models are not always appropriate for attainment demonstrations, but they can be valuable in improving our understanding of the interactions among atmospheric processes. Even better research tools than the numerical predictive models describe above such as the UAM are process numerical models, which allow coupling between processes specific to air quality modeling and meteorology.
Process numerical models typically are formulated by adding pollutant emissions, chemistry, and transport into an existing meteorological model rather than simply using the meteorological. The relatively nonreactive behavior of CO makes it an ideal chemical species for simulation in a weather model. Despite advances in air quality modeling capabilities over the last 30 y, many improvements are still possible and needed, particularly in the numerical predictive models, which are used more widely than process numerical models.
One problem is that the vertical and horizontal resolution of both types of models is too coarse to capture the variability in pollutant concentrations, which is necessary to identify local hotspots. Most numerical predictive and process numerical models are based on statistical representations of atmospheric motion on scales smaller than the spatial resolution of the models.
When unusual meteorological conditions occur, the validity of these representations becomes questionable and could lead to errors in the prediction Pielke Models used for regulatory purposes can suffer the loss of realism as a result of such shortcomings.
Various models have been applied to predict future pollutant concentrations, particularly with the goal of identifying conditions that might create an episode. Numerical predictive models can be used, as can simpler empirical models, which attempt to identify statistically significant relationships between specific air quality variables and a set of predictors.
Empirical models typically use regression or neural-network techniques to develop a relationship based on observations of meteorological variables and pollutant concentrations. Future air quality can be predicted by using the output of weather-forecast models as values for the predictors. CO is a pollutant that impairs the ability of blood to carry O 2 to body tissues. Exposure to CO at sufficiently high concentrations can cause headaches, exacerbate heart problems, lengthen reaction times, and affect fetal development.
On the basis of a compilation of scientific knowledge about the relationship between various concentrations of ambient CO and their adverse health effects, EPA set CO standards of a maximum 1-h average concentration of 35 ppm and a maximum 8-h average concentration of 9 ppm.
Even though. CO remains in the outdoor air long enough to penetrate the indoor environment and is not removed by filtration. Because the measures taken to reduce CO emissions typically result in reduced emissions of copollutants, such as PM 2. Controls on CO emissions, particularly in the form of improved vehicle technology, have led to significant reductions in ambient CO concentrations throughout the United States. However, a few locations still experience concentrations that approach or exceed the CO 8-h health standard.
Most of those areas have meteorological conditions such as frequent inversion or stagnation conditions or topography such as being situated in a mountain valley that inhibit ventilation and allow CO to accumulate at high concentrations near the surface. One such location is Fairbanks, Alaska. The task of the Committee on Carbon Monoxide Episodes in Meteorological and Topographical Problem Areas was to assess approaches for predicting, assessing, and managing episodes of high CO concentrations in meteorological or topographical problem areas.
The rest of this report describes the CO problem there, including its physical characteristics, the emissions-control strategies used there, and the prospects for the area to remain in attainment with the NAAQS for CO. Carbon monoxide CO is a toxic air pollutant produced largely from vehicle emissions.
Breathing CO at high concentrations leads to reduced oxygen transport by hemoglobin, which has health effects that include impaired reaction timing, headaches, lightheadedness, nausea, vomiting, weakness, clouding of consciousness, coma, and, at high enough concentrations and long enough exposure, death. In recognition of those health effects, the U. Most areas that were previously designated as "nonattainment" areas have come into compliance with the NAAQS for CO, but some locations still have difficulty in attaining the CO standards.
Those locations tend to have topographical or meteorological characteristics that exacerbate pollution. In view of the challenges posed for some areas to attain compliance with the NAAQS for CO, congress asked the National Research Council to investigate the problem of CO in areas with meteorological and topographical problems.
This interim report deals specifically with Fairbanks, Alaska. Fairbanks was chosen as a case study because its meteorological and topographical characteristics make it susceptible to severe winter inversions that trap CO and other pollutants at ground level. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website. Jump up to the previous page or down to the next one.
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Do you enjoy reading reports from the Academies online for free? Sign up for email notifications and we'll let you know about new publications in your areas of interest when they're released. Get This Book. Visit NAP. Looking for other ways to read this? No thanks. Page 20 Share Cite. Page 21 Share Cite. The committee will address the following specific issues: Types of emissions sources and operating conditions that contribute most to episodes of high ambient CO.
The public-health impact of such episodes. Page 22 Share Cite. Page 23 Share Cite. Page 24 Share Cite. Page 25 Share Cite. CO Exposure. Page 26 Share Cite. The relationship between indoor and outdoor CO concentrations can be evaluated with a simple differential mass-balance model Shair and Heitner that has the following steady-state solution when we combine active ventilation and passive infiltration into a single air-exchange term: 1. Page 27 Share Cite.
Therefore, the solution is 2. Page 28 Share Cite. Page 29 Share Cite. Page 30 Share Cite. Areas in Nonattainment for CO. Page 31 Share Cite. Page 32 Share Cite. Page 33 Share Cite. Page 34 Share Cite. Page 35 Share Cite. Page 36 Share Cite. Page 37 Share Cite.
Page 38 Share Cite. Page 39 Share Cite. TABLE 1—2 National CO Emissions Inventory Estimates for Source Category Thousands of Short Tons Point- or Area-source fuel combustion 5, Electric utilities Industry 1, Residential wood burning 3, Other Industrial processes 7, Chemical and allied product manufacturing 1, Metals processing 1, Petroleum and related industries Waste disposal and recycling 3, Other industrial processes Onroad vehicles 49, Light-duty gas vehicles and motorcycles 27, Light-duty gas trucks 16, Heavy-duty gas vehicles 4, Diesels 2, Nonroad engines and vehicles 25, Recreational 3, Lawn and garden 11, Aircraft 1, Light commercial 4, Other 5, Miscellaneous 9, Slash or prescribed burning 6, Forest wildfires 2, Other Total 97, Source: EPA a.
Page 40 Share Cite. Page 41 Share Cite. Cold-Start Emissions. Page 42 Share Cite. New-Vehicle Certification Programs. Page 43 Share Cite. Strategies to Address Emissions-Control Failures. Page 44 Share Cite. Page 45 Share Cite. Page 46 Share Cite. Page 47 Share Cite. Page 48 Share Cite. Page 19 Share Cite. Login or Register to save! Stay Connected!
Exposure During Episodes Additional efforts should be made to monitor personal exposures to CO in buildings and garages near high-CO areas, outside in residential locations, and in motor vehicles. Copollutants The expected adverse health effects of exposures to copollutants is another reason to consider enhanced CO controls.
During the Worst Year in — Consequently, there is no secondary welfare standard for CO. CO contributes indirectly to climate change because it participates in chemical reactions in the atmosphere that produce ozone, which is a climate change gas. CO also has a weak direct effect on climate. For these reasons, CO is classified as a short-lived climate forcing agent, prompting CO emission reductions to be considered as a possible strategy to mitigate effects of global warming.
Indoor CO levels can be considerably higher than outdoors. There are a number of potential sources of CO indoors, including gas stoves, malfunctioning or improperly vented gas appliances i.
During the cold season CO poisoning cases tend to increase. These are most often related to elevated indoor CO levels resulting from use of improperly vented space heaters and use of gas ranges to heat the house.
Fires burning over large areas in North America and Russia in some years can be an important source. The MOPITT observations often show that pollution emitted on one continent can travel across oceans to have a big impact on air quality on other continents. Carbon monoxide is a trace gas in the atmosphere, and it does not have a direct effect on the global temperature, like methane and carbon dioxide do.
However, carbon monoxide plays a major role in atmospheric chemistry, and it affects the ability of the atmosphere to cleanse itself of many other polluting gases.
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