The Department of Corrections announced the step Wednesday, the same day two guards at Somerset state prison and several guards and medical staff at Albion state prison reporting feeling ill.
Pennsylvania is now reporting 29 employees getting sickened starting Aug. 6 in ten western and central prisons. Symptoms include dizziness, lightheadedness, nausea and skin tingling.
The department says it doesn't know how long the lockdown will last.
In the meantime, it's suspending prison visits, closing mailrooms to non-legal mail, using extra caution with newly arrived inmates and requiring all employees to use gloves and other protective equipment.
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