All operations normally performed in the processing of shade-grown tobacco for use as cigar wrapper tobacco, if performed prior to the stemming process and for such use, are included in the exemption. As a whole, this processing substantially changes the physical properties and chemical content of the tobacco, improves its color, increases its combustibility, and eliminates the rawness and harshness of the freshly cured leaf. In the process the leaves are piled in ``bulks'' of about 4,000 pounds each to undergo a ``sweating'' or ``fermentation'' process in which temperature and humidity are carefully controlled. Proper heat control includes, among other things, breaking up the bulk, redistributing the tobacco, and adding water. Proper fermentation or aging requires the bulk to be reconstructed several times. This bulking process may last from 4 to 8 months. When the tobacco is properly dried, cured, fermented, and aged, it is moved to long tables where the leaves are individually graded and sorted, after which they are tied in bundles called ``hands'' of about 30 to 35 leaves each, which are then baled for shipment. Equipment required for the work may include a steam-heated plant, platforms, thermometers, bulk covers, baling boxes and presses, baling mats and packing, sorting, and grading tables. (See Mitchell v. Budd, 350 U.S. 473, 475.) Employees performing any part of this processing prior to the stemming process, including the operations named in section 13(a)(14), may come within the exemption if they are otherwise qualified and if the tobacco on which they work is being processed for use as cigar wrapper tobacco.