Except for a few instances, namely California and Missouri, the 95% retention
factor for nonheatset web is widely accepted by numerous state agencices.
There is two sources of reference. The first is the 1993 draft CTG for Offset
Lithography and the second is the Battelle study on ink oil retention in Non-
Heatset Web Offset Newsprint.
The Ink Oil Retention in Non-Heatset Web Offset Newsprint study released in
January, 1996 was sponsored by the Graphic Arts Education and Research
Foundation (GAERF) and substantiates the assumption in the U.S. Environmental
Protection Agency's draft Control Techniques Guideline (CTG) for Offset
Lithography that 95% of nonheatset web ink oil is retained in the printed
substrate. In fact, the results showed retention factors of 96.22% for virgin
and 100.55% for recycled newsprint, which are higher than those allowed by the
The four-year study was designed to find out how much petroleum ink oil is
lost from printed sheets during the nonheatset web printing process and how
much petroleum ink oil in commonly used black ink is lost from nonheatset web
newsprint during storage of up to 20 hours. To answer the first question, one
petroleum-based black ink was printed on both virgin and recycled newsprint at
0% and 50% ink coverage. The ink oil content of the sample printed sheets,
designated as 0-hour samples, was analyzed 10 minutes after printing. This
analysis showed an ink oil loss during printing of 3.78 ±3.39% for virgin
newsprint and –0.55 ±3.54% for recycled newsprint. The second evaluation
showed no evidence of ink oil loss over the 20-hour storage time. The sheets
were stored at room temperature.
Printing, sampling, and analysis were conducted by Battelle Memorial
Institute, Columbus, Ohio. Technical guidance was provided by a joint review
committee of industry representatives.
USEPA has recognized ink oil retention in AP-42 Compilation of Air Pollutant
Emission Factors. The fourth edition, Volume 1, September 1985 assigns a 40%
retention factor for heatset inks and 100% for web offset newspaper.
Newspapers printed via lithography use the nonheatset web process.
Other air pollution control agencies have also reviewed the data and accepted
the use of ink oil retention for lithographic inks. Based on my personal
experience with permitting, Wisconsin New Jersey, Ohio, Florida, Illinois, Kansas,
Texas, and Minnesota, the states of Virginia, Pennsylvania, Massachusetts,
Indiana, Georgia, and several air quality management districts in California
have accepted the ink oil retention factors.
Let me know if you need any additonal information