Think you’re picky about toilet paper? We use machines and specially trained sensory panelists (wouldn’t you want to be able to list that on your résumé?) to see which rolls combine strength, softness, and convenience
How strong? We stack and insert 15 sheets of each toilet paper into an Instron, an apparatus normally used for sturdier stuff. It slowly pushes a steel ball through the sheets. The force required to punch through the paper is measured and recorded using computer software. Stronger papers can withstand three times as much pressure as the weakest ones before ripping. The Instron also determines how hard you’d need to pull to rip two sheets along their perforation, called tearing ease.
How soft? Sensory panelists check for softness in a temperature- and humidity-controlled room so the toilet-paper fibers are evaluated under controlled conditions. They first make soft, circular motions over each sample with their fingertips to form an overall impression of softness. Next, they test for pliability by gently manipulating the paper into a ball. The roughest, stiffest papers feel pointed, ridged, and cracked; the softest tend to be more pliable and conform smoothly to the hand.
Going with the flow. Disintegration testing reflects how well a paper will move through a home’s plumbing. We put a sheet of a paper and a 2-inch stirring bar into a water-filled beaker set on a stirring plate. The time it takes for the sheet to disintegrate provides the score.
The incredible shrinking roll
In a classic “Seinfeld” episode, Jerry’s pal Elaine finds herself in a paperless bathroom stall, unable to persuade her stingy neighbor to spare a square. Many Consumer Reports readers say that the cheapskate rap applies to TP makers, too, for shaving sheets or size from their rolls and using fine print, packaging tricks, and doublespeak to mask the shrinkage.
A version of this article appeared in the May 2012 issue of Consumer Reports magazine with the headline "Toilet Paper."