ISLAMABAD (UNHCR) - The number of individuals checked in the year since the UN Refugee Agency introduced state-of-the-art iris recognition tests for refugees seeking assistance to return to Afghanistan passed the 200,000 mark this week.

The use of the biometric data - unique to each eye - allows the UN High Commissioner for Refugees to detect anyone who has previously been "enrolled" in the data base and is seeking assistance for a second time.

"This is the first time UNHCR has used such biometric checks," said Hasim Utkan, UNHCR Representative in Pakistan. "Although there were initial hesitations about how well it would work, it has proved very successful, meeting not only the cultural needs of the refugees but the operational requirements of UNHCR."

Since a test project began last October in Peshawar, about 202,000 refugees seeking UNHCR help under the voluntary repatriation programme have been checked. Testing was carried out for the first months of this year on all returnees above the age of 12 - about 55 percent of all refugees going home from Pakistan.

The age of those tested was lowered to six years during July to ensure children were not being forced to make repeated trips with various adults - an abuse of the assistance programme and a danger to the children. About three-quarters of all returning refugees are now checked by the iris centres. Only those with physical impediments or who are too young to use the equipment are exempt.

This is the first field-use of such iris technology anywhere in the world and it has performed flawlessly despite the harsh conditions in the heat and dust of Pakistan's border territories with Afghanistan. In addition to fixed locations, UNHCR has operated with mobile units to ease the return of refugees from remote areas.

The actual enrolment process takes only a few seconds from when the returnee sits in front of the camera. Images of the iris, which appear on an adjoining computer screen, are transmitted to the computer server. The system converts the image into a digital code, which is then checked against the entire data base from all iris centres to see if there is a duplicate.

If the code has not appeared before, the refugee is registered and given clearance to receive an assistance package on arrival in Afghanistan. Returnees are entitled to a travel grant that varies with the distance, food and some non-food items like shelter material. If the test reveals that the refugee has been enrolled before - and only about half of one percent are found to be "recyclers" - the person is refused assistance.

"We feel very confident with this technology that the assistance is reaching those who really need the help of UNHCR to repatriate," said Mr Utkan.

Fears that refugees might be intimidated by the technology have proved unfounded. Since only the eye is seen on the screen, few have raised the traditional objection to photographing women's faces. Women staff of UNHCR conduct the tests on women and children.

No information is recorded that can identify the individual tested - the code describing the iris has no link to the name, age, destination or anything else about the refugee. Even the code, which is useful only for detecting a second attempt to receive assistance, is held solely by UNHCR.

The technology was developed by Iridian Technologies of the United States and was installed for UNHCR in Pakistan by BioID Technologies of Switzerland.

UNHCR now operates two iris verification centres in Pakistan on a Sunday to Thursday basis - in Quetta and Peshawar - and one at Ali Zai in Pakistan's border Tribal Areas that operates only on Monday.

In addition, both Peshawar and Quetta operate mobile teams that can test groups at the refugee camps to speed their departures. An experimental iris testing centre operates in the city of Khost to see if the system can be used in conditions inside Afghanistan.

UNHCR's voluntary repatriation programme runs until 2005 and iris testing will remain a key part of the verification process next year. Last year some UNHCR assisted more than 1.5 million Afghans to return - almost all before the introduction of iris checks - and returns this year are more than 320,000.