Indoor Nanoparticles Measurements in Workplace Environment: The Case of Printing and Photocopy Center.

Irena Grgić,Jožica Bratec,Marija Bešter-Rogač

doi:10.17344/acsi.2016.2269

Abstract

In recent studies, laser printers and photocopy machines have been identified as important sources of indoor air pollution with fine and ultrafine particles. In this work, the indoor pollution of a printing and photocopy center in Ljubljana, Slovenia was investigated. The particle number concentration time series and the particle size distributions were measured continuously for a period of one month by a scanning mobility particle sizer (SMPS). Our measurements clearly showed that during operating hours the total number concentration of nanoparticles (size between 15 and 750 nm) increased in both working rooms with laser printers as well as in a room with photocopy machines. In rooms with laser printers the bimodal particle size distribution was frequently observed (i.e. max. at ca. 20 or 30 nm and at ca. 100 nm), with the aged particles persisted in the room over the night and over the weekend. In the photocopy room the situation was different, again with a sharp increase in concentration of small particles (ca 20 nm) and their growth to bigger sizes, but after closing a decrease to the background concentration. The results undoubtedly proved that the fast increase in nanoparticles (size below 50 nm) was associated with processes, the intense laser printing and photocopying activity. Our study also confirmed that the ventilation of the room is a very important factor which affects the life time of aged nanoparticle in the indoor environment.

Highlights

Nowadays we spend the majority of our lifetime, professional and private, in different indoor environments
Many studies have reported that laser printers and photocopy machines emit besides volatile organic compounds (VOCs) and ozone, fine and ultrafine particles.[1,2,3,4,5,6]
The indoor pollution of a printing and photocopy center in Ljubljana, Slovenia was investigated for the first time

Summary

Introduction

Nowadays we spend the majority of our lifetime, professional and private, in different indoor environments. The studies on indoor pollution due to the emissions of nanoparticles from laser printers and photocopy machines are mostly related to the particle concentrations and size distributions[1,9,10] and to possible formation mechanisms.[8,10] Measurements on particle emissions in the realroom environment[7,10] and studies on modeled office environment can be found as well;[5] the influence of different parameters, such as fuser roller temperature on the emissions of laser printers was studied.[7,11] The majority of particles emitted from laser printers is volatile and of secondary nature, i.e. formed in the air through the reactions of VOCs and semi volatile organic compounds (SVOCs) originating from paper and/or hot toner with ozone.[8] In addition, Barthel et al.[12] reported on elemental analysis of fine and ultrafine particles, and the elements identified (e.g. Si, S, Cl, Ca, Ti, Cr, Fe) were mainly connected with toner and paper. The SMPS was in the corner on the shelf at about 0.75 m from the ground with the sampling tube at about 2–3 m to the machines (Figure 1)

Experimental

Results and Discussion

Conclusions