Tölvatech Tips for Living #1

Dealing with Plastic Bags

Thin plastic bags such as produce bags or office wastebasket liners are often difficult to separate.  This is a necessary step after removing bags from a roll and before lining a wastebasket or inserting produce.  To open the bag by separating the sides of the lip, first locate the open end of the bag.  Then gently breathe moist air onto both outer surfaces of the plastic.  It will help to open your mouth wide and exhale slowly yet deeply onto the plastic.  Now use your fingers to slide the two plastic layers apart with a shearing motion.  

Why does this work so well?  There are two factors.  One is that humid conditions encourage static charge to dissipate.  A second, more significant factor, is that human skin rapidly softens as humidity rises.  Your fingertips will quickly, seemingly instantly absorb moisture from the surface of the plastic.  They soften and conform to the plastic sheet, raising the coefficient of friction between fingertip and bag above the coefficient of friction for the interface between the inside surfaces of the bag.  

Why should you breathe on the bag and not your fingertips?  The goal is to get as much moisture onto the contact area between your fingertips and the bag as possible.  For this it is best to start with the wettest possible exhalation, which implies a breath of warm, moist air.  To transfer as much of the moisture from this volume of air to a surface, it is most effective to choose a cool surface to encourage condensation of water vapor.  In my experience plastic bags are usually noticeably cooler than my fingertips.  

Are there simpler solutions?  There are lots of things I haven't tried: spitting or crying onto the bag, using a rubbery watch band or naturally tacky areas of my skin, or banning the use, sale, transfer, or ownership of plastic bags.  Maybe you, dear reader, will think of some novel solution!

Disinfecting and Cleaning with Diluted Bleach

A dilution of household bleach with water by a factor of 1:500 by volume is good for cleaning toys, eating dishes, and utensils.  This is pretty close to 1/5 teaspoon bleach per 2 cups water.  It's easier to measure out 1/4 teaspoon and the extra strength will not hurt.  If you put this in a spray bottle, label it carefully.

A dilution of household bleach with water by a factor of 1:9 is suitable for high level disinfection of hard surfaces that have been in contact with blood or bodily fluids.  You can prepare this from the following options:

• 3.5 tablespoons in 2 cups of water
• 1 cup in 2.25 quarts water

To disinfect hard surfaces, clean them first and then apply this solution.  Let stand at least one minute, longer in cold temperatures.  

A dilute mixture of bleach with a surfactant is good for general household cleaning tasks.  To provide the surfactant, choose an ammonia-free detergent.  Avoid dish detergent, they often contain ammonia. You can mix the following recipe in a spray bottle.

After mixing, check for the following signs of a chemical reaction.  If you see them, loosen the bottle cap and place it in a well-ventilated area far from people, children, and pets, and leave it there until any fumes dissipate.  This will take an hour or two.  

Signs of a chemical reaction include warmth, new bubbles forming in the solution, precipitation of solids, color changes, and excess fizzing.  

Household cleaner recipe:

• 2c water
• 2tsp household bleach
• 1tsp laundry detergent (ammonia-free)

I recommend wearing gloves when using this solution.  If anyone with sensitive skin will come in contact with surfaces you clean with this solution, I also recommend a plain water rinse afterward.  

Remember, clean first and then disinfect!