(a) "M-1" Restricted Industrial. Areas for industries, research facilities, and offices of a restricted nature which will have little or no detrimental effects on neighboring urban land uses.
(b) "M-2" Limited Industrial. Areas for limited processing and storage of agricultural supplies, grain, building materials, oil and gas well equipment storage and sales, plus sand and gravel extraction.
(c) "M-3" General Industrial. Areas which because of their access to transportation and community services; and relative isolation from other urban uses provide good sites for most types of heavier industries.