VOC stands for volatile organic compounds. While the actual definition is complex and depends on the type of products in which they are used, VOCs can generally be thought of as the solvent content of consumer products like polishes, cleaners, and paint removers and architectural and industrial maintenance coatings like paints and water repellants. Regulating (restricting) the amount of VOCs in products is one of the many ways government entities are trying to reduce air pollution by controlling the amount of hydrocarbons released into the atmosphere. Most common solvents and petroleum products like mineral spirits, xylene, toluene, methyl ethyl ketone, alcohols, turpentine, etc are all considered VOCs. The Federal EPA has set standards for the VOC content of various products, which all areas of the country cannot exceed. Many states and regions like California and major metropolitan areas like the greater NYC region have set much stricter standards. In an effort to deal with pollution on a regional basis the Ozone Transport Commission (OTC), consisting of the states of ME, NH, VT, RI, CT, NY, NJ, PA, MD, DE, the District of Columbia, and northern VA was formed. As of January 2005 new standards are in effect for NY, PA, NJ, MD, DE, northern VA and the District of Columbia. The New England states will soon be adopting similar standards. The maximum VOC content of many products has been significantly lowered. While many products can be converted to water based chemistries or higher solids versions, the most challenging product group is Water Repellants. These fall under the category of Waterproofing Concrete / Masonry Sealers. The most effective and visually acceptable products are based on solvent soluble, silicon containing compounds that are applied in fairly dilute solutions to allow them to penetrate deeply. The solvent of choice traditionally has been some form of relatively inexpensive mineral spirits. The new regulations in the OTC regulated regions prohibit the sale and use of the older formulations. To maintain the quality and effectiveness of the products, special solvents that are not considered VOCs have replaced the majority of the solvents in certain ShoreBest water repellants. All ShoreBest products meet the Federal standards. Those containing the special solvents to meet the stricter OTC standards have the designation OTC VOC 400 in their names and are legal to use in the OTC member states. Purchasing Federally compliant products in states where they are permitted and using them in more restricted jurisdictions is a violation of state and/or local laws. No product should be diluted with solvent prior to use. Check with the state or local environmental / air quality regulatory agency for the regulations in the area in which a project is planned.