Recently, Otto the Inchworm went to the gas station with his mother and noticed stickers on the gas pumps that said This Device Sealed and Approved.  "Why are those stickers on all the gas pumps?"  he asked his mother.  Otto's mother did not know but said she would try to find out.   Otto knew that whoever put them there would be in big trouble.  The last time he put stickers on the walls of his room, his father wouldn't let him watch TV for three days!  Otto's mother asked the attendant about the stickers when she paid for the gas.  The attendant didn't know either.

The next day Otto went to the grocery store with his Uncle Ken.  He was surprised to see that the scales in the deli department had the same stickers as the gas station.  Then he saw the same stickers on the scales in the meat and fruit departments and even on the candy scale.  Now Otto was really confused.  He turned to his uncle and said, "Uncle Ken, I saw those stickers yesterday at the gas station.  Who put them there?"  Uncle Ken didn't know.  He said he would try to find out.  Otto chuckled at the thought of someone going for a month with no TV for putting those stickers all over things that probably didn't even belong to them.  Uncle Ken asked the cashier about the stickers but she didn't know either.

By Saturday Otto had almost forgotten about the stickers.  He decided to go to the car wash with his friend Jimmy and Jimmy's sister Joan.  Joan just bought her first car and washed it every Saturday, whether it needed it or not.  It was an old car with more rust than metal but it ran well and was safe and Joan loved it anyway.   Otto and Jimmy liked to sit in the car with their faces pressed against the window and let Joan spray the hose at them.  When they got to the car wash, Joan gave Otto the quarters since it was his turn to deposit the money.  Otto reached up to drop a quarter in the slot and he couldn't believe what he saw.  Another one of those stickers!  "I won't ask. I won't ask," thought Otto.  "No one knows what they are anyway."  So, Otto didn't ask, and Joan washed the car, and the boys made faces through the window.

Monday was Career Day at school. Otto's teacher, Ms. Harris, told the class that they would have people visiting from state government.  She said that the students could ask whatever they wanted, but to please "be polite and ask questions that are about the visitor's jobs." 

The first speaker was a health inspector named Ms. London.  She talked about bacteria and why you should wash your hands before you eat.  In a dish she had grown bacteria that was gray and black and uglier than any mold Otto had seen in his refrigerator.

The second speaker was Mr. Price. He had cases full of weights that he called "test weights".   Some were in pounds and ounces and some were kilograms and grams and then there were some very tiny weights.  Mr. Price had stainless steel cans with long necks that he called "test measures" and a fancy electronic scale that he said he used for "package checking".

And then Otto saw them!  He saw the stickers that had been on the scales at the gas station, and the car wash --  the same stickers no one could explain!

He listened as Mr. Price explained about being a weights and measures inspector.  He said that they test and inspect all kinds of commercial weighing and measuring devices.  Commercial devices are those used to buy and sell products and services.  Mr. Price gave examples like scales, from large ones that weigh trucks to small ones that weigh gold.  He also said he tested gas pumps, taxi meters, timing devices (like laundromat dryers, car washes and parking meters) and meters that measure fuels, fertilizers and pesticides.

Otto's hand shot up and he asked, "What are you looking for when you test all this stuff? I see the stickers everywhere but I still don't know what it means."

Mr. Price explained, "Inspectors are checking to make sure that scales, meters and other equipment are working properly and being used correctly.   For example, the only way to know that a scale is working properly is to test it by putting weights on it.  If things aren't working right then you could pay too much for what you are buying or the store could loose money."

Otto interrupted, "Now I understand! When you test something and it's ok, you get to put a sticker on it!"

"Exactly," said Mr. Price.  "You will also find us in all kinds of stores checking packaged products to make sure they have as much in them as the wrapper says they do.  This means that when you buy a box of cereal that says it weighs one pound, the contents should weigh one pound, not less.  If you buy a package with 6 candy bars that weigh two pounds, you should get 6, not less, and at the labeled weight of two pounds.  Actually, anything you buy or sell will be by some kind of measurement;  from firewood by the cord to pet food by the pound.  It all involves us in some way."

Ms. Harris said they were almost out of time but she wondered if Mr. Price would tell the students how they could be good shoppers.  Then they could help their parents save money.

"Otto didn't know it, but he was being a very good shopper," said Mr. Price. "He noticed the weights and measures approval seals.  This is sensitive equipment and it's very important to take care of it, test it and use it properly."

Everyone thanked Mr. Price as he packed up his weight kits and other test equipment.  Otto got out a book and leaned back in his chair, relieved. At last, the case of the mysterious stickers was solved!

How to Help Your Parents