For our own safety, we should start paying attention to Walmart’s intercom system. Here’s what you should know.

When shopping at big stores like Walmart, do you listen to the intercom or do you ignore it? It’s very common for people to tune it out like it’s white noise. 9 times out of 10, it has nothing to do with us, the shoppers. For example, when you hear “Code Spark” at Walmart, they need help at the checkouts because the lines are getting too long. It’s an “all hands on deck” call. Believe it or not, there are special Walmart codes that we as customers need to know.

Unfortunately, mass shootings in public places are an all too common reality for us here in the United States. Michigan is nothing new with this tragedy. And yes, there is a code for it. Code Brown stands for Active Shooter, according to CommonCentsMom.com.

There’s also a code with a heartbreaking backstory: “Code Adam.” Code Adam is named after a 6-year-old boy who was abducted from a Sears store in Florida in 1981 and found dead. His father, John Walsh, was more than just an advocate for missing children, according to Time.com.

In 1984, John Walsh co-founded the government-funded National Center for Missing & Exploited Children, and four years later he became host of America’s Most Wanted.

Below is a complete list of Walmart codes you should probably know.

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