Airbnb is updating its safety features after a shooting at a California listing last week.

CEO Brian Chesky announced on Wednesday at The New York Times DealBook Conference four changes the company will be implementing. The changes were also announced in an email to employees Wednesday.

Here are the four key changes:

1. All listings will be verified by the end of 2020 by a combination of the company and guests. Chesky said that he wants to “make sure we can stand behind every single listing and host,” for photo accuracy, the correct address, and safety.

2. Airbnb will now have a guest guarantee in the scenario that guests arrive at a listing and the listing does not match photos and descriptions.

3. A 24/7 hotline with real people will be available to address issues that come up.

4. Airbnb will review what it calls "high-risk" listings.

Chesky said on stage at the conference that trust is necessary for Airbnb to exist, which is why the company is making these changes.

"Over the course of the last 10 years, what we created, what we invented, wasn't really a way to book a home," Chesky said. "What we invented was a way for strangers to trust one another to stay in homes." He took to Twitter to explain the safety guarantee.

According to Chesky, about 2 million people stay in Airbnbs every night, and most are without incident, but "a tragedy happens, and enough is enough," which is why the company is adding these safety standards.

In addition to responding to the shooting in California, these safety measures also appear to be a response to a recent Vice report by Allie Conti on Airbnb scams. Conti discovered listings owned by the same person that were not the same as the description on the site. Guests had to stay in other accommodations, and had little recourse for a refund through Airbnb.

Airbnb has had a tough month with these incidents, and Jersey City residents voted yesterday to impose stricter regulations on the company. Airbnb has announced that it intends to go public in 2020.