HOW MUCH CARBON MONOXIDE IS TOO MUCH

Always check with The Authority Having Jurisdiction.  Know who is in the building being tested.

ASHRAE 62-89 (American Society of Heating, Refrigeration and Air Conditioning Engineers)

009 PPM   The maximum allowable concentration for continuous (24 hr) exposure.  ASHRAE states the ventilation air shall meet the out door air standard referenced to EPA and 9 PPM.

EPA (Environmental Protection Agency)

009 PPM   This level or lower as an ambient air quality goal averaged over eight (8) hours. This outdoor air standard is exceeded in many urban areas due to auto exhaust.

Common Action Level

009 PPM or more above what you measured outside is the most common action level in the U.S. by local Authorities of Jurisdiction for further testing.  Some jurisdictions require fuel shut-off until problem diagnosed and corrected.

BPI  (Building Performance Institute)

10 to 35 PPM is a marginal level in reference to potential or foreseeable problems in some situations.  Occupants should be advised of a potential health hazard to infants and small children, elderly people and persons suffering from respiratory or heart problems.  If building has attached auto garage, document CO levels in garage.  Accept this level as normal where unvented appliances are in use.  These levels are unacceptable when originated from vented appliances.

36 to 99 PPM is excessive.  Medical alert.  Conditions must be mitigated.  Ventilation required.  Always test garage space.  Individually test combustion appliances.  All repairs are to be conducted by a qualified technician with proper test equipment.

100 to 200 PPM is dangerous (and is a common building evacuation standard.)  Medical alert conditions exist.  It is suggested that occupant health inquiries be conducted.  It is advisable that someone else transports them to seek medical help; 15 minute maximum exposure upon discovery.  Report incident to Authority of Jurisdiction.

ACGIH (American Conference of Governmental Industrial Hygienist)

25 ppm – maximum 8 hour TWA (Time Weighted Average)

EPA

035 PPM   This level or lower as an ambient air quality goal averaged over one (1) hour.

Common Action Level

035 PPM is also a common action level for fire department or other emergency responders to utilize self contained breathing apparatus when occupation of that environment is to be sustained by that responder.

035 PPM or less averaged over an 8 hour day within that workday is a common goal of specific States Occupational Health and Safety Administration or similar state entity.  This is also a common goal of many employers despite higher regulated concentration standards and may require the measurement of several simultaneous reference locations.

OSHA  (Occupational Health and Safety Administration)

050 PPM   Maximum allowable concentration for a workers continuous exposure in any eight (8) hour period.  This 8-hour average requires continuous measurement and accurate reporting in the workplace.

Any increase in PPM from outside to inside warrants further source investigation and is documented, reported and even fixed is common in jurisdictions where a fuel supplier also is considered an Authority of Jurisdiction.  This standard is also common to some federally and state funded weatherization programs as well as protocol to some private companies engaged in carbon monoxide testing.

Every home or building where people live, work or play should have a carbon monoxide alarm detector.  Please install one that meets the needs of all people.  Read the instructions and install them to the manufacturers specifications.  Please note the health advisory listed on all alarm packages.

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