The group is now calling for government officials to consider regulations regarding laser printer emissions. The study also found that particle levels in the office increased fivefold during working hours due to printer use, and the printers in question emitted more particles with a new toner cartridge or when printing graphics and imaged that needed more toner. Most worryingly was that the researchers found that "one of the printers released particles into an experimental chamber at a rate comparable to the particle emissions from cigarette smoking." Of the remaining models, 37 released no particles that diminished air quality, six released only low levels and two released medium levels. The particles, believed to be toner, can potentially be inhaled deep into the lungs, unless the room is well ventilated, where scientists say they could pose a "significant health threat". Research studying 62 different laser printers has shown that 17 out of 62 models tested could be classified as "high particle emitters" due to large quantities of ultrafine particles being released by the machines.