One of the challenges in restoring items of antique furniture is preserving or reapplying an original finish. Solvents used in applying finishes to old furniture are no longer permissible under current air quality regulations. Denatured alcohol, used with shellac, mineral spirits or naphtha, used with varnishes, and toluene, xylene and other solvents used with nitrocellulose lacquers, all contribute to air pollution and consequently can no longer be used. The dissolving solvents used in some waxes are likewise no longer permitted. What do you do when you have a valuable old piece which needs to be treated with the original finish to preserve its character and value?
The State of California actually has a provision in its air quality regulations to allow the use of historical finishes which are non-compliant. This rule, called emissions averaging, allows the use of non-complaint materials as long as on a monthly basis--computed daily--the use of those materials does not cause a permitted business to exceed its emissions limit. Does that sound complicated? We have actually tried to condense and simplify a very complicated set of formulas and regulations. In simple language, if overall a business uses a very small amount of VOCs (volatile organic compounds--materials which contribute to air pollution), it may be permitted to use the high VOC solvents necessary to reproduce historical finishes. This is not automatic for all businesses, a business must apply for this special permit and obtain it before using these high VOC materials. It must then keep daily records of a rolling 30 day average of all usages, non-compliant and compliant, and submit those for review each year.
It might surprise you to learn that for thirty years no one had obtained this permit at the time we first applied for it. Since we were a guinea pig concerning emissions averaging, it actually took us 3 1/2 years to obtain it after we applied. Since we use very low VOC water based finishes for the refinishing we do, we are able to occasionally use these non-compliant finishes and still stay well below the permitted emissions level. The good news is that we can now use these otherwise illegal solvents when needed to reproduce historical finishes.
We think it important to point out that you can go nowhere else in the state for historical finishes if you wish to work with a compliant business. Why insist on working with a compliant business? That assures you of two important things. First, you know you are dealing with a company that values integrity and is seeking to work in an open and law abiding way. Second, you know you are dealing with a company that is doing its part to ensure we have healthy air to breathe. Makes sense, doesn't it?