To limit the spread of Covid-19, the U.S. Centers for Disease Control and Prevention recommends that individuals practice social distancing. When local conditions allow for retail stores to open, they confront a variety of guidelines that vary by state. For example North Carolina places specific limits on the number of customers allowed per square foot, while Oregon generally advises that the number of customers in the store should be limited so that customers can remain six feet apart. Whether or not customers are required by law to wear masks in stores depends on the state. How retailers implement these guidelines also varies among types of retailers and even within store categories. Grocery stores, for example, have adopted a wide variety of specific methods to ensure that customers remain apart.