Jay Draper pulls into the Ahtanum General Store and pumps five gallons of high-grade gasoline into a measuring canister on the back of his trailer.
Although he stops the pump at exactly five gallons, the reading on his canister is slightly more.
"So he's giving the customer some," he says before grabbing the medium grade spigot to test it.
With countless families hitting the highways for vacation, more than a few occasionally wonder if they are getting their money's worth at the pump - especially when gas prices seem to rise each summer.
Draper is just one of 14 inspectors with the state's Weights and Measures Program who make sure motorist get a square deal.
Gas pumps are generally checked on a 28-month cycle. The one Draper is checking this day was last inspected in February 2007. He knows because stickers are placed on pumps informing customers when they were last inspected.
Pumps are allowed a plus or minus margin of error of six cubic inches ó which amounts to about six ice cubes ó for each five gallons measured.
Pumps that come up short more than that amount are taken out of service until they are brought into compliance.
If pumps come up short three times or more of the allowable margin, then station owners could face fines anywhere from $100 to $5,000 per violation, something that rarely occurs, says state Weights and Measures manager Kirk Robinson in Olympia.
"We try to work with them," he says. "A lot of times just taking the device out of service usually motivates the owner to get into compliance."
But it's not just gasoline meters and quality that they're inspecting. The office also checks large truck scales, grocery store food scales and cash registers to assure accurate weights and prices.
"Our job is just to monitor to make sure everyone is doing good business," Robinson says.
His office, which is under the state Department of Agriculture, handles about 700 complaints a year, of which only about 22 percent are valid, he says.
Much of those complaints come when there is a spike in gas prices, he says.
One of the more common complaints is meter jumping, when the meter jumps to five cents before its lever is pushed to pump gas, a problem often caused by a vapor lock in the system, he says.
Problems are found in only about 8 percent of the state's roughly 52,000 fuel pumps, he says.
Half of those pumps end up giving customers more than what the meter says, he adds.
"It's about a 50-50 split in ones taking away or giving to the customer," he says.
While Draper inspects the amount of fuel each dispenser at the Ahtanum General Store is pumping on this recent morning, his colleague, Shane Snyder, is checking octane and ethanol levels and whether there is any presence of water in the fuel.
Snyder fills a clear jar with fuel and finds no sign of clouding that the presence of water would cause.
Working from the back of his truck, he pours some of the fuel from the jar into a smaller one with a lid and sets it atop an electric device that uses an infrared light to measure octane and ethanol levels. It's octane level 91.9.
"Which is fine," he says as he pours the fuel back into the larger jar.
Each grade of fuel must meet national octane and ethanol standards.
All fuel that is tested or measured goes back into the station's underground tanks from which the pumps draw from.
Next, Snyder puts a paste on a long wooden measuring stick and drops it into one of the underground fuel tanks.
Water turns the paste white. Diesel storage tanks are only allowed one inch of water at the bottom. Ethanol fuel tanks, only a quarter of an inch.
Snyder pulls out the stick, and it shows less than an eighth of an inch.
Condensation naturally accumulates in tanks, and station owners make pumping it out part of routine maintenance, Robinson says.
If storage tanks have more water than allowed, the fuel cannot be sold until the water is pumped from the tank, which can be done without removing the fuel.
"They don't like to be shut down, like any business, so they're usually right on it," he says.
Copyright (c) 2010, Yakima Herald-Republic, Wash.
Distributed by McClatchy-Tribune Information Services.