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Title 40

Displaying title 40, up to date as of 6/09/2026. Title 40 was last amended 6/08/2026.
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Table 4 to Subpart IIII of Part 63—Default Organic HAP Mass Fraction for Petroleum Solvent Groupsa

You may use the mass fraction values in the following table for solvent blends for which you do not have test data or manufacturer's formulation data

Solvent type Average
organic HAP
mass fraction
Typical organic HAP, percent by mass
Aliphatic b 0.03 1% Xylene, 1% Toluene, and 1% Ethylbenzene.
Aromatic c 0.06 4% Xylene, 1% Toluene, and 1% Ethylbenzene.
a Use this table only if the solvent blend does not match any of the solvent blends in Table 3 to this subpart, and you only know whether the blend is aliphatic or aromatic.
b E.g., Mineral Spirits 135, Mineral Spirits 150 EC, Naphtha, Mixed Hydrocarbon, Aliphatic Hydrocarbon, Aliphatic Naphtha, Naphthol Spirits, Petroleum Spirits, Petroleum Oil, Petroleum Naphtha, Solvent Naphtha, Solvent Blend.
c E.g., Medium-flash Naphtha, High-flash Naphtha, Aromatic Naphtha, Light Aromatic Naphtha, Light Aromatic Hydrocarbons, Aromatic Hydrocarbons, Light Aromatic Solvent.