On Fri, 15 May 2009 00:31:07 -0500, "bw" wrote:


Even most Health and Safety people consider 5,000 ppm (1,300% above
current levels) to be safe.


But that is a maximum. The problem that can result from
closed buildings is more from faulty equipment though, the usual
doors and windows are not "airlock" quality.

True. ASHRAE suggests engineers use a design limit of 1000 ppm housing.
Most house ventilation is designed for 4 people not to exceed 1000 ppm.


Frankly, forced ventilation is a really stupid and
irresponsible concept.

A similar stupid concept is law requiring no clearing of brush
or burning of waste, a well designed combination incinerator-
power plant would be an asset for any community, but the
nutty extremists would rather have landfills and rotting wood
producing methane and CO2.