California Mandates Lighter Textbooks
Most textbooks are made with 45-lb. book paper. Moving to a 40-lb. sheet, for instance, can reduce total book weight by 12.5%, depending on the type of cover stock used, says Dave Dauncey, quality assurance manager of lightweight coated operations at Domtar Inc., in Ottawa.
The use of lighter basis-weight textbook sheets is not without precedent. Teacher's editions, with their supplementary work notes and lesson plans, often contain up to 20% more pages than student's copies.
Yet teacher's and student's editions are usually similar in weight, due in large part to the use of lightweight sheets. But going with lightweight papers raises durability concerns among textbook buyers, says the AAP's Driesler.
Students are rougher on textbooks than teachers. And one textbook typically has to last between six and eight years. With most school districts needing to maximize textbook lifespans, durability is a chief concern.
"Less durable books mean they must be replaced more often, perhaps annually, and this would result in a significantly increased cost to school systems," Driesler says.
That's the bad news. The good news: The durability and opacity thresholds set by the National Association of State Textbook Administrators (NASTA), the Book Manufacturers' Institute (BMI), and the Association of American Publishers are the same for 45-lb. papers and lighter weight papers.
NASTA specifications require 40-lb. to 44-lb. paper to have a minimum average tearing strength of 28 grams in each direction, when tested according to TAPPI T-414 (TAPPI is the Technical Association of the Pulp and Paper Industry).
This is the same spec for 45-lb. to 49-lb. papers. The bursting strength specification is no less than 16 points (psi), when tested according to TAPPI T-403, for 40-lb. to 44-lb. basis weights, and 45- lb. to 54 lb. basis weights. (Bursting strength is the amount of uniform pressure, in pounds per square inch, required to pull a sheet of paper apart.)