The union says it fears for the safety of its employees, given the level of public anger over changes to the EI system that could affect seasonal workers.
"We're putting employees in situations that are very dangerous," Larry Rousseau, a spokesman for the Public Service Alliance of Canada, said Thursday.
He spoke following a report by The Canadian Press that public servants have been making unannounced visits since January, as part of an examination being conducted while the EI program is overhauled.
During those visits federal employees have been hand-delivering questionnaires and requests for people to appear at their regular EI interviews.
Prime Minister Stephen Harper defended the house calls when asked about them Thursday.
"Every year, unfortunately, in our employment insurance system hundreds of millions of dollars are identified or are lost through false, or fraudulent, or inappropriate claims," Harper said while in Saskatoon for an unrelated announcement.
"One of the jobs of Human Resources and Skills Development Canada is to ensure that the funds in the employment insurance system are there for people who have lost their jobs, who qualify, and who need that help."
About 1,200 EI beneficiaries will be receiving the visits, through the end of next month. A group of 50 federal civil servants have been assigned to make the house calls.
"We've been hearing from (civil servants) who have gone to houses ... and they've been badly received," Rousseau said.
"What will it take — an untoward or unfortunate incident (for these visits to stop)? Why do we have to test the limits of people's patience like this?"
From now on, people who frequently claim EI are expected to accept any job for which they're qualified, within 100 kilometres of home, as long as the pay is 70 per cent of their previous salary.
They must also prove they're actively seeking work.
Opponents say the plan is particularly harsh on Atlantic Canada and Quebec, which have a number of seasonal industries.
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