What Are the Uses of Perlite?

Construction Applications

• Perlite is used in construction projects because of its light weight and insulating properties. It is often used to fill cement blocks and crevices prior to the application of mortar. Perlite is fire-resistant, making it a great insulator for roof decks. This natural volcanic glass reduces noise, increases fire ratings and is resistant to vermin.

Gardening

• Perlite is widely used in horticulture, especially in soil-less growing-mix applications. It does not absorb water but retains it in its pores. Its moisture-retaining qualities allow oxygen to circulate through the mix while still providing the plant with necessary moisture. When used in plant beds, perlite's pH renders the mix sterile, preventing the growth of weeds. Perlite is used in residential and commercial gardening.

Industrial Applications

• Perlite is used in geothermal wells, food products and abrasive soaps and cleaners. Its fire-resistant property reflects its use in the manufacture of refractory bricks, mortar and pipe insulation.

Health Hazards

• For many years, the presence of asbestos in perlite has been a great concern for both suppliers and users. According to the findings of the Perlite Institute, there are currently no sound data to support the presence of asbestos in perlite. The two minerals are rarely if ever present in the same deposit. The U.S. Environmental Protection Agency has been concerned with perlite particulate emissions, which occur during the expansion process from the dryers, expansion furnaces and handling operations when sulfur-containing fuels are used. This results in the emissions of sulfur dioxide, a common but dangerous air pollutant. Sulfur dioxide pollution can lead to emphysema and premature deaths. Investigation determined that expansion furnaces emit trace elements such as aluminum, calcium and mercury. However, since perlite expansion process primarily utilizes natural gas, there were no significant emissions of sulfur dioxide.