Numbers Don't Lie--or Do They?
by L. Carol Christopher
Although scientists can now clone complex mammals, our industry can't guarantee the repeatability of newsprint test results. Go figure.
Ruth Felland Bohner, NAA's director of production materials, says that high-quality newsprint can help newspapers achieve the reproduction results that lead to happy advertisers and higher bottom lines. To that end, she says, some papers are setting specifications on a wide range of paper characteristics, including roughness, optical properties, basis weight and tear strength.
But before you can set specifications, Bohner warns, you have to know what you're measuring. Accordingly, the NAA/CPPA/AF&PA Technical Newsprint Steering Group will begin educating the newspaper and newsprint industries about testing methods. Part of the project involves explaining that the exact same samples, tested at different times and places, can produce different test results.
While variability has been a problem for years, we are just beginning to quantify it. Round-robin testing by the Technical Association of the Pulp and Paper Industry found enormous variations in results from the same samples tested in different labs. Such variability can come from the lab, the equipment, the tester and/or the time between tests. But that doesn't mean you should throw away your lab goggles--while your results may not show the same numbers as those of your paper producer, yours and theirs are probably correlated.
Bohner advises: Find a sheet that works well in your plant, measure it and keep records. Then find another sheet that works and measure that one. Eventually, you can determine upper and lower limits for what works at your site.
John D'Alessandro, quality-services manager for Gannett Co., agrees. He recommends determining your tolerances precisely, tracking consistency among shipments and regularly calibrating your equipment to industry standards--this will help ensure that the results you get are consistent enough to correlate with those of your paper producer.
Tracking this correlation will help you obtain the high-quality paper you need.
L. Carol Christopher is president of Christopher Communications in Berkeley, Calif. E-mail, cchristo@weber.ucsd.edu; phone, (510) 444-7841.