Exposure Levels

• Carbon monoxide exposure levels are measured in parts per million or ppm. Though the Environmental Protection Agency allows up to 9 ppm exposure levels for an eight-hour period, all levels of carbon monoxide exposure are dangerous --- most are lethal. In 1989, the "New England Journal of Medicine" published a study that showed the negative effects of 2 percent carboxyhemoglobin levels on individuals with carbon monoxide poisoning. The effects occur within seconds to minutes or minutes to hours, depending on the concentration. Levels under 35 ppm at one-hour increments can cause several long-term effects.
  
  

Influenza-Like Effects

• Many symptoms of carbon monoxide poisoning resemble influenza or food poisoning. Carbon monoxide exposure up to 35 ppm causes light-headedness and dizziness. You could feel weak and collapse from muscle fatigue. However, you will not produce a fever from carbon monoxide poisoning, nor will you ache as you would with influenza. These symptoms usually appear in the presence of carbon monoxide. The severity of your symptoms will vary depending on your location and the concentration of the gas. Carbon monoxide poisoning should be an investigative issue --- especially, if everyone in your household is sick, simultaneously.
  
  

Long-Term Respiratory and Cardiovascular Effects

• The EPA regulates carbon monoxide under the Clean Air Act. However, extended, low concentrations of carbon monoxide can cause breathing complications. Your lungs and heart slowly begin to shut down from oxygen deprivation. Without oxygen, you cannot function properly. The EPA allows you to be exposed to carbon monoxide at 35 ppm for no longer than an hour. That does not necessarily mean that exposure is totally safe, however. At the current safety standards, carbon monoxide saturates the air enough to take up 2 percent of your blood's hemoglobin. It is deemed tolerable. Carbon monoxide inhalation at 35 ppm can cause worse damage faster than damage would occur at lower levels. Unlike influenza-type symptoms, these exposure effects do not dissipate once you are away from the toxic area. Chronic respiratory and coronary heart diseases could develop over time.
  
  

Neurological Effects

• After weeks of extended carbon monoxide exposure at low levels, you can experience several neurological issues. Your brain is one of the most sensitive organs influenced by carbon monoxide poisoning. You can develop short-term and long-term memory loss or worse, amnesia. You can find yourself often confused about things. Your balance and coordination will seem offset. Vision can be impaired. Personality and behavioral changes can occur. Your brain function will decrease, possibly resulting in permanent brain damage.
  
  

Acute and Lethal Effects Above 35 PPM CO Exposure

• Carbon monoxide poisoning happens rapidly at higher concentration levels. Nausea and vomiting are prominent. Severe headache and convulsions are possible. You can lose consciousness as well. Carbon monoxide in an enclosed area can become concentrated. An idling car in the garage or a misused gas-powered appliance can cause excessively dangerous levels in your home. You could slip into a coma or die if you don't receive help immediately. Death occurs within two hours at 800 ppm carbon monoxide exposure, 30 minutes at 1,600 ppm, 20 minutes at 6,400 ppm and within 3 minutes at 12,800 ppm. You will be knocked unconscious by two to three breaths at 12,800 ppm.