What the limit is
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The requirement
A manufacturer or importer of a consumer product subject to the subpart ensures that the VOC content levels in Table 1 are not exceeded, for any product manufactured or imported on or after 10 December 1998.
Why it exists
Volatile organic compounds contribute to ground-level ozone. Consumer products are a large aggregate source precisely because so many of them are designed to evaporate, and an air freshener is the clearest case.
Expressed as weight-percent
A percentage of the finished product by weight. That means a dense non-volatile ingredient dilutes the figure and a light solvent raises it, and it means the calculation is done on the formula rather than estimated from the carrier.
Air freshener is a named category
With the limit depending on the form: an aerosol, a pump spray, a solid or a gel are treated separately, because they deliver very different quantities of solvent into a room.
The reported figures
Single-phase aerosol 70 weight-percent, double-phase aerosol 30, liquid and pump spray 18, solid and gel 3. These come from search results rather than from Table 1, which would not serve to us from three sources.
Which makes 18 the number for this property
Every leaf here is a pump spray. If the reported figure is right, an air freshener in this format has 18 weight-percent to spend on everything volatile, fragrance included.
Confirm it before it costs you
A formula developed against a wrong limit is a formula redeveloped. The current table is the thing to read, and it is a five minute check against a decision that shapes the whole product.
States can be stricter
California's own consumer products regulation is the one most often cited in this category and it is not identical to the federal standard. Selling nationally means meeting the tighter of the two wherever both apply.