“Tens of millions of vehicles with Takata air bags are under recall,” an NHTSA site devoted to the recalls says. “Long-term exposure to high heat and humidity can cause these air bags to explode when deployed. Such explosions have caused injuries and deaths.”

According to the NHTSA, there are 50 million defective Takata airbags in 37 million U.S. vehicles. Many of them are in states such as Texas and California, where years of hot, humid weather can cause a chemical propellant in many Takata airbags to explode, sending shrapnel into vehicle passengers.

Florida, Georgia, Alabama, Hawaii, Louisiana, Mississippi, and South Carolina are also considered states where persistent hot and humid conditions can put defective airbags at a higher risk of exploding during a crash.

The NHTSA’s site hosts a database of vehicles affected by the Takata recall. Consumers can type in their vehicle identification number to see if they need to replace their airbags. The agency warned that more vehicles will soon be added to the recall, bringing the total number of affected air bags to between 65 million and 70 million by December 2019.

Takata filed for bankruptcy-court protection in the U.S. and Japan last year and was eventually bought for $1.6 billion by U.S.-based Key Safety Systems. The Japanese company faced tens of billions of dollars in costs and liabilities resulting from almost a decade of recalls and lawsuits.

Air bags with Takata’s defective inflators have been linked to at least 180 injuries and 20 deaths. Automakers such as Ford, Nissan, Toyota and Mazda have paid out hundreds of millions of dollars to settle consumer loss claims. The recall, the largest in U.S. history, affects vehicles from 19 automakers.

Clarification, Aug. 30, 2018: The language of this article has been edited to clarify the particular conditions in which the airbags become dangerous.