Time Zones appear in two places in Recruiting as described here. 

At the Company Level: 

1. Log in and go to People > Hiring > Applicant Tracking. The Active Jobs screen appears. 

2. At the top click Admin and select Company Settings. 
3. On the left, click Address, Time Zone.
4. By default, when you create users, the have the time zone associated with your Company's account.

Your Account Info in Recruiting: 

1. Log in and go to People > Hiring > Applicant Tracking. The Active Jobs screen appears. 

2. On the top right, click the Gear (settings) icon and select Account Info.

3. In the User Information section on the right, calendar invitations use the Time Zone appearing here. 

iCal files automatically change to the recipient's time zone: 

• Because Recruiting sends invitations as .iCal files (the default Calendar file that most scheduling software uses, including Gmail, Outlook, Yahoo! Mail, Apple Mail, and more), when a recipient receives the .iCal, it automatically converts to their default Time Zone. 
• Example:
  • If a user has their Time Zone set to Pacific Time (PT) and sends a Calendar Invitation for a noon meeting, and the recipient has a Gmail account with Mountain Time (MT) selected, the recipient receives a meeting request for 1:00 PM. MT.