Dear @b_itchy. You have likely correctly identified the trigger of your hive (urticaria). A skin prick test will help to identify the allergen that you are sensitive to. You might wish to consult your Family Physician/ designated workplace doctor to assist you in finding out the allergen and workplace modifications can possibly be done to reduce your exposure to the allergens.  Anti histamines such as zyrtec are safe for regular consumption and helps in treating urticaria. You might wish to take anti histamines prior to exposure of your allergens in order to prevent or reduce the severity of your urticaria. Hope this helps.