Dry weather and dish-pan hands have been blamed for problems with the new smart ID cards, with some applicants' thumbprints unable to be scanned. The Immigration Department has confirmed that in some cases, its scanners have been unable to pick up the prints, which are required to verify that the applicant is the person pictured on the card. After one such case, a woman told the Post about her experience last week. 'After we'd tried about 10 times to get the thing to read my thumb, they had me rub my hands together thinking the warmth might bring out the lines - it didn't,' said the woman. 'Then the officer ... smothered my hands in moisturiser, but that didn't work either, no matter how much he put on.' She said the officer explained that the machines had difficulty scanning the thumbs of people with finely detailed hands and dry skin. This was particularly true for domestic helpers, whose constant contact with cleaning products seemed to make one in 10 of their thumbprints unreadable. 'He [the officer] got quite worked up,' she said. 'He complained that domestic helpers' bosses did not always give them gloves, and when they did, the helpers refused to use them, which made their hands unreadable.' The woman said that after a few more attempts, she was asked to go through an alternative check. 'It was something he referred to as an 'automated verification procedure',' she said. This involved four or five immigration officers looking at the photo on her ID card. 'They asked me if I agreed that the person in the photo was me, which I did. Then they let me pick up the card.' Senior immigration officer Wong Kwok-kiu said the scanners were reliable but they occasionally had difficulties.