Pomodoro technique using RicRac Stopwatch

As a software developer I have been looking at possible ways to increase productivity, recently I have spent a couple of days looking at the time management technique called Pomodoro. The basic process is to do increments of work which last for 25 minutes and then have a 5 minute break these are called pomodoros, then after 4 pomodoros you take a longer break of about 20 minutes. 

To do this I downloaded the RicRac Stopwatch, installed it and made a second copy by coping the directory, this then gave me 2 copies which I could have 2 different settings for, the first with a 25 minute countdown and the second with a 5 minute countdown. RicRac stopwatch worked well doing this, the issues I had was with the technique itself, my main criticism of the technique is that I work in an open plan office, and people constantly interrupt, which breaks the increments. For this technique to work I think I would need to be in a quite office or work from home.