Meat plants sometimes get advance notice of inspections by the Health and Safety Authority (HSA) and inspectors have found a "high level of compliance" with measures to combat Covid-19 at meat plants during the pandemic.
SA inspectors have carried out 34 inspections at meat and poultry processing plans since May 18.
The State watchdog's findings come following recent outbreaks at meat processing plants in the Midlands.
They raise questions about how the virus has spread at plants and the effectiveness of inspections in helping prevent outbreaks.
Siptu officials have called for unannounced inspections and mandatory testing of workers to combat Covid-19.
Manufacturing division organiser Greg Ennis said there are unacceptably high rates of infection of workers, which are running at approximately 10pc.
The authority said in a statement that it did not issue any enforcement notices to meat processing employers because it found the level of compliance was satisfactory.
It said it was involved in reviewing matters relating to meat processing facilities as a member of a National Outbreak Control Team, which is chaired by the HSE.
"Further to its involvement in the National Outbreak Control Team, the authority undertook some 34 inspections which covered each of those meat processing facilities connected with a Covid-19 outbreak along with a number of other meat processing facilities," the HSA said.
A number of these inspections included subsequent follow-up visits and joint inspections with public health officials.
"These inspections checked compliance against the interim guidance on Covid-19 outbreaks in meat processing plants in Ireland published by the National Outbreak Control Team, the return-to- work safely protocol and general health and safety requirements," it said.
"The authority has received a high level of co-operation from management, staff and contractors in plants inspected and has noted an overall responsiveness to guidance and advice issued both onsite and subsequently.
"Based on the inspections and investigations carried out, the HSA identified a generally high level of compliance with the recommended measures to limit the spread of Covid-19 in a workplace context, in line with the interim guidance issued by the National Outbreak Control Team."
It said authority inspections are generally unannounced, but in certain circumstances "limited advance notification may be required".
"For example, where it is essential for inspectors to meet with specific individuals at the place of work or to ensure a particular work activity is being undertaken so as to allow inspectors to observe," it said.
The authority said a limited number of inspections may also require the "coordination of resources" from State agencies or Government departments.
It said this scenario could also lead to the employer being notified shortly before the inspection is due to take place.
Since the first phase of the Government's reopening plan to the end of last week, the authority has undertaken 3,820 inspections and investigations of workplaces across the economy.
Of these, a total of 2,844 inspections "addressed Covid-19".
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