The Federal Aviation Administration (FAA) plans to hit Amazon.com Inc. for shipping potentially dangerous goods by air. The FAA proposed that Amazon pay $350,000 in fines.

In 2014, the online retail giant shipped a product called “Amazing! LIQUID FIRE” from Kentucky to Colorado by air. The container holding the product was not properly packaged nor labeled correctly and leaked. As a result, nine UPS employees who came in contact with the container were treated with a chemical wash.

What makes the case especially alarming is the fact that not only were the containers improperly labeled with emergency response information, but the employees handling the materials did not have proper training.

Shipping makes up about 90% of the world’s trade, and strict guidelines are in place to prevent such occurrences. The fact that Amazon was able to get away with transporting hazardous material in such a way makes the situation even more serious.

According to Gizmodo, the FAA has had its eye on Amazon for some time. In the last two years, it claims that the company “has violated the hazardous materials rules 24 times.” The company paid $91,000 as an apology for sending flammable liquid adhesive.

The FAA is not just focused on Amazon but is cracking down on other companies violating shipping guidelines. The Wall Street Journal states that the FAA issued more than $4.5 million in civil penalties for improper shipment of dangerous materials aboard an aircraft.

Amazon is expected to place stronger measures on its shipping capabilities in the future.

“As they try to do more of the distribution using their own network of air and ground services, knowing the distinction between what can go by ground and what can go by air will become more and more important,” said Satish Jindel, founder of SJ Consulting Group Inc. “Before, when they were smaller, they didn’t have to make as many distinctions between ground and air.”