Table 4.

Example of biocidal products used for airborne surface disinfection (ASD).

Product	Forms	Conditions of use	Advantages	Disadvantages	Occupational exposure limits (ppm)a
Formaldehyde	Liquid	3–10%	Broad spectrum of activity	Highly irritating, toxic, mutagenic, carcinogenic by inhalation	2
Formaldehyde	Gas	4–10 g/m3, 18–22°C and 70% humidity	Broad spectrum of activity	Highly irritating, toxic, mutagenic, carcinogenic by inhalation	2
Glutaraldehyde	Liquid	2%, optimal pH: 8	Broad spectrum of activity	Irritant, toxic to the skin and respiratory tract. Activity greatly reduced in the presence of soiling	0.05
Chlorine derivatives	Liquid	Optimal pH: 6–7	Broad spectrum of activity	Aggressive. Toxic disinfection by-products. Activity reduced in the presence of soiling	0.5
Chlorine dioxide	Gas	Soluble in water	Broad spectrum of activity Unlike hydrogen peroxide gas, it can tolerate a wide range of temperature and humidity	Produced in situ, corrosive	0.1
Peracetic acid	Liquid	Relatively unstable: decreases by 0.4% per month	Active at low concentrations in the presence of organic and inorganic soiling	Irritating to eyes and respiratory tract	–
Hydrogen peroxide	Gas–liquid	Useable from 5 to about 35%. Relatively unstable	In fumigation: faster and safer than formaldehyde. More stable than peracetic acid. Greater activity in the gas/liquid form	Depending on the procedure may require humidity to be controlled at low level. Some devices are expensive	1

ASD methodological guide published by the French ANSES agency (27).

^aBased on the Directive 2009/161/EU and the British List of approved workplace exposure limits EH/40 (2011). Values for long-term exposure limit: time-weighted average over 8 h.