Monday, May 6, 2013

Bleach Disinfecting and Sanitation

We all need to have some bleach on hand for daily sanitation and laundry needs. If our drinking water should become compromised because of storms or because we are in a remote area and uncertain as to how safe it is then we need to use bleach for the disinfection the water if boiling the water is not possible. Boiling drinking water provides the safest water.

To SAFELY use bleach as a disinfectant or sterilizer you must have the proper measuring and testing tools. These are an ‘eye dropper’ and ‘Chlorine Test Strips’. The eye dropper can be purchased at any drug store for $1.50 and the chlorine test strips from any swimming pool supply store for $6.00 to $30.00 for 50 test strips. You will need to have two sizes or ranges of test strips; 1-25ppm and 1000-10000pmm. The chlorine test strips are very important especially if you are storing water. With the test strips you can monitor the chlorine level throughout the year. Remember, chlorine dissipates with age and this could leave your stored water unprotected and unknown to you not safe to drink!

To provide accurate information I researched the use of bleach from Universities to major health and rescue organizations and came up with the following recipes or dosing for the most common uses in disinfection and sanitizing. The bleach should be between 5¼% to 6% concentration unscented household bleach.

Water Emergency Disinfection
2 ppm to no more than 4 ppm (EPA Maximum recommended ppm)
1 quart = 2 drops
1 gallon = 8 drops
5 gallons = ¼ teaspoon
10 gallons = ½ teaspoon
50 gallons = 2½ teaspoons

(Instructions from Clorox:)
When boiling of water for 1 minute is not practical, water can be made potable by using unscented bleach. Prior to addition of the sanitizer, remove all suspended material by filtration or by allowing it to settle to the bottom.

Decant the clarified contaminated water to a clean container and add 12 drops or 1/8 teaspoon of this product to 2 gallons of water (2 drops to 1 quart). Allow the treated water to stand for 30 minutes. Properly treated water should have a slight chlorine odor. If not, repeat dosage and allow the water to stand an additional 15 minutes. The treated water can then be made palatable by pouring it between clean containers several times.

Note; it takes 45 minutes to kill Giardia Protozoan (common cause of diarrhea) with a 1 ppm chlorine level. So waiting 60 minutes before drinking treated water is a good idea just incase you have Giardia in the raw water.

For cloudy water, use 24 drops or 1/4 teaspoon of this product per 2 gallons of water (3 drops to 1 quart). If no chlorine odor is apparent after 30 minutes, repeat dosage and wait an additional 15 minutes.

Garden Vegetable Rinsing
¼ teaspoon per 1 gallon water = 25 ppm (Clorox recommendation)

Thoroughly clean all fruits and vegetables. Prepare a sanitizing solution of 25 ppm available chlorine. Spray mist on submerge the fruit or vegetables and let rest for 2 minutes then rinse with clean water.

Disinfecting Solution
½ cup per 1 gallon water = 2400 ppm (Clorox recommendation)

Apply solution and let stand 5 minutes then rinse with clean water. (You can use this solution in a trigger sprayer to get into difficult small spaces, just remember to spray with clean water after the 5 minutes of soaking to rinse off all the chlorine).
A common everyday disinfecting solution used for; Kitchen Countertops, Bathroom Areas, Tubs and Showers, Toys, Garbage Cans, Refrigerator Interiors, most all hard surfaces and items.

Sanitizing Cutting Boards, Food, Meat Processing Equipment
1 cup per 1 gallon water = 5,000 ppm (CDC recommendation)

Bleach solutions used for disinfecting must remain wet on the surface for an adequate amount of time to be effective. This is often referred to as Contact Time or Dwell Time and can vary depending on the dilution and type of microorganism you are trying to kill. For example, a 10 minute contact time with a higher-strength solution containing at least 5000 ppm is recommended by the Center for Disease Control (CDC) for the hard-to-kill spore form of Clostridium difficile. After sufficient contact time, the surface should be rinsed with clean water to remove bleach residue. This helps to minimize surface damage and is especially important when using bleach to disinfect toys or food-contact surfaces.

The above information was taken from a variety of trustworthy sources including numerous Universities. I have discovered that there is no golden rule that everyone abides by when it comes to bleach/water mixing ratios for specific tasks. I selected and posted the most commonly agreed to ratios.

This is the most complete bleach water information I’ve found. Download and save!

Red Cross:



1 comment:

  1. Mike,

    Great information, thank you for posting and doing the research.