Portable Refueling Stations

This page last reviewed May 13, 2010

Image of portable refueling stations

Description of the Source Category

Portable refueling stations are stand-alone plastic or metal containers, generally between 10 and 30 gallons in size, which are used to store and dispense fuel to vehicles or equipment such as tractors, lawn mowers, boats, generators, motorcycles, etc. They are generally on wheels, or are capable of being carried. Fuel dispensing is through gravity feed hoses, a hose and nozzle assembly, or a 2-way rotary hand pump.

The Air Resources Board (ARB) staff is conducting tests to determine if proposing a regulation to control reactive organic gases (ROG) emitted from portable refueling stations is necessary. These portable refueling stations (plastic and metal) are used for dispensing gasoline to vehicles and equipment at farms, businesses, marinas, military bases, and residences.  Any proposed regulation would reduce gasoline permeation and vapor loss emissions from the portable refueling stations and auxiliary equipment, such as plastic hoses and nozzles.

Test Procedures
Testing procedures varied depending on type of tank. Metal tanks were assumed to not have permeation issues (except for hoses) and were tested for vented emissions, or for vented and permeation when hoses were included in the testing. Plastic tanks were tested for permeation and vented emissions. Permeation testing for hoses for both plastic and metal tanks is currently pending. Select tanks and hoses will be tested using E6 and E10 fuels.
Example Testing Procedures:
Test Procedure for Plastic Tanks
Test Procedure for Metal Tanks
Test Procedure for Hoses  (draft  pending)

Gravimetric Test Procedure

Estimated Baseline Emissions

The portable refueling tank source category population has been estimated and projected over ten years, as of 2008, based on manufacturers reports of units sold in California. This does not account for units in use prior to 2008. Emissions data has been projected for 10 years based on these estimations.

Emissions testing for the source category include hydrocarbon emissions from tank permeation and evaporation, hose assembly permeation and evaporation, and refueling emissions. Testing using E6 fuel is almost complete, and testing with E10 fuel pending.

Staff estimates that in 2018, (based on testing data, to date) diurnal emissions from portable refueling stations (excluding hoses and pumps) may be 159 to 226 tons per year (tpy) of ROG, and 6.2 to 8.8 tpy from refueling losses. An estimated total emission from all sources is from 165 to 235 tpy ROG. (This estimate is based on units sold in California in 2008 and sales growth estimates for 10 years. It does not take into account units already in use.) Actual emissions are considered to be higher. This translates to an annual fuel loss of between 55,000 to 78,360 gallons. Assuming $2.50 per gallon of gasoline, the cost of fuel lost through permeation, evaporation and refueling would cost between $137,500 and $196,000 per year for these portable refueling stations.

Emissions Test Data Summary , Diurnal Emissions Chart, Emissions Factor Chart Emissions Projections for Source Category

Control Strategies

The control strategies that are being considered for this category include permeation controls for tanks, (such as fluorination and sulfonation), evaporative controls for tanks and caps, low permeation hose assemblies, and refueling loss controls for tanks. Most of the technology needed to reduce emissions from this category already exist and have been implemented for PFCs, SORE, and other off-road categories.

In limited testing, fluorination of a test tank reduced emissions by approximately 83%.

Previous emissions testing of other source categories showed sulfonated and fluorinated plastic containers significantly reduced emissions from permeation.

Contacts: Angus MacPherson 916-445-4686;