When many people go to the local pool for a swim, they don’t think twice about the delicate chemical balance required for the water to be safe for swimmers — they assume there are people responsible for checking that — and they’d be right. 

But according to the Lincoln, Neb., Journal Star, city inspectors worry those tasked with checking the pool's chlorine and pH levels may not be doing so correctly.

In 2013, Lincoln closed 133 pools after inspections revealed that the water did not meet quality standards — which may indicate that water testers are making errors during testing.

Under current regulations, lifeguards at a pool can handle pool tests with little training in the correct testing processes.

Pool water is tested by adding a chemical to a small sample of pool water and stirring the sample to turn the water pink. Then another chemical is added to return the water to its original color.

“It’s like a chemistry test,” Scott Holmes, Environmental Public Health Division manager for the local department, told the Journal Star. “You have to add the correct number of drops. You have to swirl and not shake.”

Under proposed changes to the outdated pool-testing rules, only certified pool operators or pool testers would be allowed to do quality checks. In order to become certified, candidates would be required to take a short class and be tested to make sure they know how to test the water. The certification class would cost $20 dollars and would make a tester certified for two years.

Testing water correctly plays a large role in helping maintain healthy pool users. When the water has the right pH and chlorine balance, it can reduce the transfer of certain types of diseases and infections.

In 2001, Lincoln suffered an outbreak of cryptosporidium, a diarrheal illness, after it is estimated that it originally spread through public swimming pools. At its peak, there were more than 133 cases of cryptosporidium that had been acquired through public swimming pools.