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Toxic Gas Emission Limits (O3, NO, NO2)

The US National Institute for Occupational Safety and Health (NIOH) suggest a ''Permitted Exposure Limit'' for NO2 of 5 ppm and NO 25 ppm over an 8-h period for these potentially toxic sub­stances. Several European countries have regulated maximal occupational exposure to 2 ppm NO2.
The CPSC (Consumer Products Safety Commission) Report from 26-09-2006 restates the FDA safe Ozone limit of 50 ppb for pro­duction by medical devices.

Dr. Corsi (Univ. of Texas at Austin) arrived at the following Ozone production limits:
Normal respiratory function
17.5 mg/hr (house)
1.3 mg/hr (office)
9.9 mg/hr (school)
sensitive population
0.45 mg/hr
0.041 mg/hr
0.13 mg/hr
This leads to an Ozone concentration of < 5 ppb .

USA ''Permitted Exposure Limit''
(over an 8-h period)

NO2: 5 ppm 

NO: 25 ppm  

FDA safe O3 limit: 50 ppb 

BCD device maximum calculated production
(per cm2 of electrode area)

1.6 x 1013 (NO + NOx)/cm2sec giving << 2 ppb/cm2
in 8 hours for a standard size room (60sqm)
Assuming no destruction of molecules

0.0016 mg/hr/cm2 giving << 0.3 ppb/cm2 in 8 hours
assuming a typical hospital usage (20 per minute)
For reference, Dr. Corsi's most stringent limits for people
with normal respiratory function was: 1.3 mg/hr/cm2 (office)

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