One source of pollution that may not come readily to mind is fuel hose at gasoline dispensing facilities. Believe it or not, gasoline can get through the walls of the hose and into the atmosphere. That is a called permeation, which in this case is the diffusion of gasoline through the solid wall of the hose.

Ohio and California Have Low Permeation Fuel Hose Requirements

And believe it or not, the permeation rates in fuel hoses vary a great deal. A hose rated at SAE 30R6 can permeate at a rate up to 600 grams per square meter per day (at 23 degrees centigrade). But a hose that is classified as “low permeation” according to UL standard 330 permeates at NO MORE than 10 grams per square meter per day (and that’s when tested at 38 degrees centigrade).

There are currently two states in the U.S. that have placed a focus on low permeation fuel hose. The State of Ohio requires gasoline dispensing facilities to install low permeation hose, where regulators estimate the move will reduce VOC emissions by 10.8 pounds per hose per year. The other is California, where the Air Resources Board (ARB) is the agency responsible for air quality and climate protection. The ARB estimates statewide emissions in California would go down by one tone each day and save approximately 1.7 gallons of gasoline per hose per day by requiring low permeation gasoline dispensing hose.

Executive Order Certifies EagleFlex Low Perm Hose

http://www.arb.ca.gov/vapor/eo_nvr1b_092715.pdf