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Proposed residential indoor air quality guidelines for formaldehyde

2. Physical and Chemical Properties

Low-molecular weight aldehydes, such as formaldehyde, are reactive, highly flammable compounds. The reactivity of formaldehyde results from the presence of a polarized carbon-oxygen double bond. At room temperature, formaldehyde is a reactive gas (Table 1).

Table 1. Physical and Chemical Properties of Formaldehyde
Molecular formula H
    \
     C = O
    /
H
Molecular weight 30.03 g\mol
Melting point -118 to -92 °C
Boiling point -21 to -19 °C
Vapour pressure 516 kPa
Conversion ppb -> μg/m3 X 1.23
Sources: Environment Canada, Health Canada 2001; WHO 1989.