The Reason Grocery Stores Blow Cold Air At The Entrance Isn't What You Think

Given that most of us shop at them at least a few times a week, it can be surprising to think about how many aspects of supermarkets we just don't understand. From what those vegetable misters actually do, to why most stores don't have windows or clocks, there are plenty of standard supermarket features that we've become accustomed to but rarely question. Another one of those questions to add to the list? Why you're blasted with a jet of cold air when you walk through the doors of a store.

If you've ever gone grocery shopping in the heat of the summer, you've likely felt an appreciation for the cool air you pass through on your way into the store. According to Taste of Home, this type of air conditioning isn't there to cool you off, nor is it there to chill the store, which has its own AC system. So what purpose does this arctic blast actually serve? 

This type of cooling is called an "air door" or an "air curtain," and it actually acts as a second type of door, keeping out dust, dirt, and pests as the supermarket's often-automated entrance doors continually slide open and closed (via Taste of Home).

A large fan installed above a grocery store door blasts cold air that helps deter pests such as mosquitos, gnats, and flies from entering, where they could contaminate store food and bother shoppers. The jet of air also keeps dust and dirt from wafting inside. Air doors also help keep the store's own air conditioning at a constant temperature, blocking too much cool air from exiting the store as its doors open and close (via ScienceABC).

Let it be known that we have a newfound appreciation for air doors — though we're still primarily thankful for their targeted hot weather relief.