Local environmental services are focused around pollution in air, water and soil. Commercial industries are regulated by a branch of a government agency that determines all compliance issues. Compliance regulations for industries may vary as determined by local government. In general, there are several areas of local environmental services that should be considered before engaging an environmental company. Not all local environmental services offer multiphase environmental assistance. If, for instance, large areas suffer concentrations of polluted air from various sources in business or residential areas, some local environmental services provide air pollution review compliance regulations as they apply specifically and help reduce sources of air pollution. Other local environmental services may be in the business of designing, installing and servicing pollution control equipment in industrial processes. Yet, other local environmental services may be involved solely in regulatory consulting from issues that deal with a residential area to larger sources of pollution in industries. Local environmental services perform specific tests using state-of-the-art equipment to determine the levels and types of pollutants in air streams. When groundwater becomes seriously contaminated, remediation is the first step to abate pollution runoff into rivers, lakes and streams as well as local sewer systems. Most residential water is controlled by a waste water treatment system that removes all heavy metals and other pollutants from the water. Compliance regulations for water standards exist to keep the levels of pollutants within safe drinking or standard water use levels. In some residences a Reverse Osmosis system (R/O) may be required to provide consistent levels of safe water into a home. Generally, testing is performed and samples are analyzed by a certified local environmental testing laboratory.