Gas regulators control the flow of natural gas (NG) and liquid propane (LP) to appliances and equipment that use them as fuel. The pressure of incoming gas is often unstable and excessively high. Regulators ensure that sufficiently-low constant pressure is maintained and sent to appliances. Proper sizing for an NG or LP regulator depends on several key factors which differ by application. Correct sizing is important due to the safety issues related to gas appliances. SupplyHouse.com carries the Maxitrol brand of gas regulators. Maxitrol offers a regulator sizing calculator for free on their website. Use it to learn the relevant sizing factors and select the appropriate gas regulator for your next job.