Section 3. Art. 244 of the Labor Code is hereby amended to read as follows:

"Art. 244.Coverage and employee's right to self-organization. — All persons employed in commercial, industrial and agricultural undertakings including religious, charitable, medical or educational institutions operating for profit, shall have the right to self-organization and to form, join or assist labor organizations of their own choosing for purposes of collective bargaining. Ambulant, intermittent and itinerant workers, self-employed people, rural workers and those without any definite employers may form labor organizations for the purpose of enhancing and defending their interests and for their mutual aid and protection."

"All religious, charitable, medical or educational institutions not operating for profit are exempt from the coverage of this Book. However, this exemption shall not apply to religious, charitable, medical or educational institutions which on the date of effectivity of this Code, have existing collective bargaining agreements or duly recognized labor organizations of their employees. Moreover, nothing therein shall preclude any employer from voluntarily recognizing any labor organization of its employees for the purpose of collective bargaining."