Travel / Buying travel insurance for staying in Poland: Help needed. [3]

I am buying winter sports insurance for my family (We are English) but are taking my Polish girlfriend with us to Zakopane. We have bought winter travel insurance for us but the polocy won't cover her so we are buying a seperate policy. I've come to the part where I'm filling in an online form and the translated version of the site (using Google translate) mentions Social Seurity number could this be PESL and just a dodgy translation?

Please help!

:)