Prevent Family Fire Act of 2019 This bill allows a new business-related tax credit for 10% of the amount of the first retail sale of a safe firearm storage device. The amount upon which the credit is based may not exceed $400. A "safe firearm storage device" is a device that (1) is designed and marketed to deny unauthorized access to, or rendering inoperable, a firearm or ammunition; and (2) is secured by a combination lock, key lock, or lock based on biometric information. This credit terminates after December 31, 2026.