We sell a lot of sanitizer test strips (chlorine, QAC, peroxide) into the foodservice industry, and we frequently get calls from folks who have a health inspector at their facility with questions they can’t answer, or they may be calling us because they just got written up. There are often questions with regards to the shelf-life or expiration date of the test strips, if the strips are being used correctly, what the results should be, etc. So today, we thought we would try to offer up some advice to help you be more proactive when it comes to some of the common health inspector issues we hear about.
First, health inspectors are usually looking for things to be under control. How can you convey this?
- Good organization of chemicals and testing supplies
- Proper storage of chemicals and test strips
- Proper training of the people using the test strips
That last one is key. This could be as simple as making sure you’re using the correct test strips. We have received calls from customers using chlorine test strips to measure QAC solutions and vice-versa. Check the label on the sanitizer solution to see what the active ingredient is. This will help you determine which test strip you should be using. If you’re still not sure, call the chemical manufacturer.
You should also know how to properly use the test strips. Read all instructions carefully to be sure you’re dipping the strip for the correct amount of time, and reading the results after the correct amount of time. Small details, like shaking off excess water, or waiting 10 seconds to compare to the color chart can have a big impact on results.
Lastly, it’s very important you understand how to interpret the results and determine the correct course of action. You need to know in advance what sanitizer levels your health inspector will be looking for, and how to make adjustments if it’s not correct.
One of the most common questions we get when a health inspector is at a facility is how to determine if the strips are expired. The easiest way to avoid this question is to purchase test strips from a supplier that prints the lot number and expiration date on the label. Alternatively, you could request that your current supplier adds this information to their label if they’re not already doing it.
If you already have test strips that don’t have a lot number or expiration date on them, you have a couple of options. The chlorine and QAC test strips are good (when properly stored) for a minimum of 24 months from the date of purchase. Write the date you received the test strips on the vial, and you can reasonably assume and assign and expiration date 18 months from the receipt. This factors in distribution time, assuming the distributor is properly rotating their stock.
If you want to know with more certainty whether or not the strips still work, you could try testing them. The first step in evaluating test strips is to visually inspect them. Plastic chlorine test strips should have a test pad that is white or just slightly off-white. Chlorine test papers should also be white or slightly off-white. Any discoloration should raise concerns.
Plastic QAC test strips should have a canary yellow test pad. If the test pad is greenish in color, it has been compromised. If the yellow color is severely faded, this would indicate exposure to intense light. The QAC QR5 test papers are yellow with a slight tint of green. The 90-second QAC test papers are more yellow-orange in color when they are still good.
To assist in a visual inspection, look at the color chart provided with the test strips. The unreacted strip should not have any more color than the lowest color block on the chart.
If you have training and access to proper glassware, you can evaluate the test strips by making standards from the sanitizer concentrate being used. This assumes that the concentrate is not compromised in any way. Caution when handling the concentrate is very important. In this instance, you would make standards to coincide with some of the color blocks on the test strip color chart. For example, if using the chlorine test paper, you could make standards at 10, 50 100, or 200ppm. Dip the strip in each standard following the instructions, and compare to the color chart. Did they turn color as expected?
Another option for validating test strips is to use a secondary technique. For example, a test kit could be used. Since the cost per test with a test kit is higher, the kit would only be used periodically to verify the solution being tested and validate the test strip results. The test strips would still be used for frequent, routine testing.
Lastly, although some distributors print an expiration date of 24 months from the date of manufacture, many of our test strips will last longer when stored properly. The expiration date could be reasonably extended up to 6 months with proper testing and good results at the time of expiration.
Ideally, you should have all of this squared away BEFORE the health inspector arrives at your facility. Being proactive and following the above advice will help you avoid having to call us in a panic while the health inspector is at your facility or avoid getting written up.