Hi, we had that too. A 3 cm long scratch on the middle pane of the triple glazing and a sand grain in another spot. Everything is allowed... we were shown the manufacturer's guidelines which state that up to 3 cm is permissible and enclosed sand grains are not considered defects. Apart from us, apparently no one notices, but we always look closely because we know where it is... annoying, but a new pane (which might again have these allowed "defects") is too expensive for us.