Yes, you can take a break during your PMP Certification Exam.
However, please note that there is no scheduled break allowed during the PMP Certification Test. The duration of the PMP certification exam is four hours, and once you start your test, the clock will start ticking until you finish the exam, or time is completed.
That being said, you can take breaks during your PMP Certification Test to go to washroom or eat some snacks, but the time taken during these activities will be counted in your exam time. The exam clock will not stop; it will continue ticking.
When you leave you test room for a break, the prometric staff sitting outside test room will check your ID and ask you to enter your name and Time Out on the log, and when you come back he will check your ID again and will ask you to write your Time In with your signature.