The WHO indoor air quality guideline proposed less than 0.08 ppm for indoor concentration
of FA [1].
The American Conference of Governmental Industrial Hygienists (ACGIH) has set a ceiling limit
for FA at 0.3 ppm [2]. FA is a known irritant to the eyes, nose and throat [3].
The International Agency for Research on Cancer (IARC) and U.S. Environmental Protection
Agency (EPA) classified FA as a human carcinogen during high or prolonged exposure