Laser Printers are a Big Source of Indoor Air Pollution
Is Your Laser Printer Harming You?
Not too long ago, Lloyd wrote about a study that pointed the finger at laser printers as big sources of indoor air pollution. That study, published in May 2008, has been followed up by a new one in January 2009 that takes a closer look at the problem. The results aren't very reassuring.Here is the abstract of the new study by the International Laboratory for Air Quality and Health at Queensland University of Technology in Australia:
While current research has demonstrated that the operation of some laser printers results in emission of high concentrations of ultrafine particles, fundamental gaps in knowledge in relation to the emissions still remain. In particular, there have been no answers provided to questions such as the following: (1) What is the composition of the particles? (2) What are their formation mechanisms? (3) Why are some printers high emitters, while others are low? Considering the widespread use of printers and human exposure to these particles, understanding the process of particle formation is of critical importance. This study, using state-of-the-art instrumental methods, has addressed these three points. We present experimental evidence that indicates that intense bursts of particles are associated with temperature fluctuations and suggest that the difference between high and low emitters lies in the speed and sophistication of the temperature control. We have also shown, for the first time, that the particles are volatile and are of secondary nature, being formed in the air from VOC originating from both the paper and hot toner. Some of the toner is initially deposited on the fuser roller, after which the organic compounds evaporate and then form particles, through one of two main reaction pathways: homogeneous nucleation or secondary particle formation involving ozone.
But don't think that all laser printers are the same when it comes to emissions. Ars Technica says: "The work involved tested two printers, an HP 2200 and an HP 1320n. The latter is known to emit many more particulates than the former, by as much as three orders of magnitude (or 100,000 percent more)".
I hope that now that these studies are out, laser printer makers will pay attention and address this problem as quickly as possible. Some poorly ventilated offices have dozens of laser printers.
For more about indoor air quality, see also: Book About Air-Filtering Plants: How to Grow Fresh Air and Best Air-Filtering House Plants According to NASA!.