Olympic security

According to an article in the Times, builders working on the Olympic site in London are going to have to pass through stringent security checks, just to get in:

About 100,000 workers at the Olympics site in London are to be screened using advanced face and palm recognition techniques in one of the largest and most expensive security operations undertaken on a British construction project.

I just wonder if anyone in government asked the suppliers to guarantee that all this equipment still works when the hands and faces being scanned are covered in concrete. 

Comments

[The Englishman]

Fingerprints of manual workers are often too degraded to be captured well - http://sphericalcube.com/biometrics/biometrics.php

Workers Lose Jobs for Worn Fingerprints - Raval and Salvador's fingerprints, read by state-of-the-art digital machines, came back "unclassifiable." The FBI said lifetimes of manual labor or old age often erode the whorls of ridges that make up fingerprints.... http://news.ncmonline.com/news/view_article.html?article_id=aae1e930a702fee05da45bc299336742

And don't even start on the how the scanners can't work if dirty or dusty....

[View from the Solent]

Even allowing for a largish number of entrances to the site, how long will it take each day to put 100, 000 people through screening ?