Effect of Toner Coverage Percentage and Speed of Laser Printer on Total Volatile Organic Compound (TVOC)

Good indoor air quality (IAQ) is essential to enhance human productivity and health. Emissions due to a laser printing in an office environment have been observed as one of the contributors to the poor IAQ. Of the various types of laser printers available in Malaysian market nowadays, this experiment chooses one famous laser printer to investigate the influence of toner coverage on the emission rates within 1 m(3) acrylic chamber. Total volatile organic compound (TVOC), carbon dioxide (CO2) and temperature were monitored in 100 pages printing job with different percentages of toner coverage. Toner coverage significantly influenced laser printer speed to 30 pages/min, 20 pages/min and 15 pages/min. Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS) were used in identifying the elemental composition from the sample toner powder collected from the laser printer cartridges. This study showed that TVOC concentration increased rapidly at the beginning of printing process at maximum value of 0.68 ppm and its concentration started to decay at 30 pages of printing for all percentages of toner coverage. Meanwhile, 50 % of toner coverage resulted in not only the highest temperature of 300.7 K but also the highest CO2 concentration which started to decay as it reached 50 pages of printing job. This study clearly shows the printer speed and the coverage of printing job could significantly influence the emission rates of compounds that reduce the quality of indoor environment.