How loadable are handles?

Hello, I am interested in how much weight the handles on the roof of the xc90 can handle. The question is that I often take a disabled woman with me in the car. So far this is no problem in the normal station wagon. It is small with limited mobility of the legs. As one hand enters the seat and with the other hand pulled up at the handle, her technique is up until now. Since my next car becomes the xc90, I see problems because of the height. I think it will then hang with the whole body weight (60kg) on the handle, whereby the load is in the short term jerky higher. Is there possibly a DIN, which says what the handles have to endure? Here are also dealers in the forum and vlt of you has already examined the roof in the area of the handles more closely and has seen that the screws store from the handle in a nut and not in such a tin threaded look greeting otto2111