These utility bills stink -- literally

Scratch-and-sniff is usually associated with pleasing scents: men's cologne, women's perfume, new-car smell.

Not so with this month's bills from Puget Sound Energy, serving 1 million-plus customers in Washington state. A pamphlet (.pdf file) accompanying the bill is infused with the odor of rotten eggs. Scratch the pamphlet and you'll know what a natural-gas leak smells like. When you smell that smell, it's time to leave the house. Right. Now.

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Some found the smelly pamphlet humorous. "But what about those eco-friendly residents who receive their bills electronically? Will someone have to mail them a rotten egg?" "michael98370" commented at the Kitsap Sun website. (Actually, those PSE customers can request a copy of the pamphlet here.) Post continues after video.

Seriously, this is excellent stuff to know, and many people don't. (Don't believe me? Ask your friends and family.) Natural gas has no odor, and leaks can be very dangerous. To make them detectable, gas companies add a substance, often mercaptan, to the gas to make it smell like rotten eggs.

It's not to be confused with hydrogen sulfide, a poisonous and flammable gas with a rotten-egg smell that can be the result of decay in sewer systems and is sometimes present in water. Read more about that here.

Odorants were added to natural gas after a gas explosion in an East Texas school in 1937 killed nearly 300 students. The explosion was reportedly felt 40 miles away. Deadly explosions are still all too common.

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What should you do if there's a natural-gas leak where you are? Some tips from PSE:

• Leave immediately -- on foot. Don't use the phone and don't turn appliances or light switches on OR off.
• Don't smoke or light a match.
• Call the gas company from another location.

Before you dig a ditch or a deep hole, call the utility company first to find out where the lines are. And if you have natural-gas appliances, buy and use a carbon monoxide detector.

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A bonus rotten-egg tip without the smell: How to tell if an egg is rotten without cracking it open? Put it in a pan of water. If it's really old, it will float.

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