How many r/m/c plants are now certified under the program of the National Ready Mixed Concrete Association?
In August 1970 the NRMC certification was held by a total of 620 plants owned by 248 companies. According to the association recent gains have been especially strong in Florida, Illinois, New Jersey and Pennsylvania. The leading states at the time the information available to us was compiled were California (81 plants), Illinois (50 plants), Ohio (48 plants) and Wisconsin (40 plants).