OK, I have some pretty useful information that might help prospective test takers. This happened to one of my friend while he was taking the test in Chennai, India prometric center. This might happen to anyone of you in any of the prometric centers around the world and I believe this info would help you in responding to such a situation. I gathered all necessary details from my friend and posting the same here.

Admin, I request you to move this thread to the appropriate section if this is not the right section. Also, request you to make this sticky if you believe this might help future test takers.

Incident in detail: This happened in late August 2013 in Chennai, India prometric center. My friend had an 8:00AM appointment for PMP test and after completing the formalities he started taking the test. After 1 hour or so, he started to face an unusual situation. It seems there was some heavy hammering happening right above him on the top floor (construction work). The sound was quite disturbing and my friend couldn’t concentrate for some time. So he said that he called the proctor and explained him the situation. The proctor immediately acknowledged the sound and said that there was a construction happening. The proctor also informed to my friend that they have already asked the construction guys to take it slow or stop the process during day time. However, this did not seem to happen. My friend then requested for a pair of ear plugs and he was provided the same. Even after that, the noise got even louder and started to disturb him further. It seems he informed the proctor again about the noise and at this point of time the proctor expressed their helplessness. Note that the conversation and actions are all being recorded in the prometric center. Now this noise seemed to have affected my friend and he ended up failing his test by a whisker. He tried to register a formal complaint at the prometric test center itself but they refused to take it (did not mention further details here as why they refused to take it) and instead suggested him to write to the PMI help desk. We tried for the contacts on the help page and found an email address. He then wrote to the PMI help desk explaining the situation in detail. The help center agreed to take up his case and after about 15 days they got back and offered a *retest free of cost*.  They even agreed to extend the 1 year validation period which was about to end by then. Also, said that they have done the investigation (seemed to have analyzed the audio and video logs) and verified the authencity of the claim.  

Now, this can happen to anyone and I wanted to give a headsup that in such unfortunate cases(test center problems) you have hope and PMI will fairly resolve your case based on the authencity of your claim. Let me know if you need any more details (post in comments section) regarding this incident. I shall be happy to help.