Characterization of Emissions from Carbon Dioxide Laser Cutting Acrylic Plastics

Abstract

Carbon dioxide laser cutters are used to cut and engrave on various types of materials, including metals, wood, and plastics. Although many are equipped with fume extractors for removing airborne substances generated during laser cutting, gases and particulate matter can be released upon opening the lid after completion. This study focused on investigating laser cutting acrylic sheets and associated emissions. Real-time instruments were utilized to monitor both particulate concentrations and size distributions, while the patented Tsai diffusion sampler was used to collect particulate samples on a polycarbonate membrane and transmission electron microscopy (TEM) grid. Identification of released gases consisted of the use of gas sampling with Teflon gas bags followed by analysis using gas chromatographymass spectrometry (GC-MS). A portable ambient infrared air analyzer was used to quantify the concentrations of the chemicals released by laser cutting activities. The results of the study found that a significant concentration of particulate matter, including nanoplastic particles ranging 15.4−86 nm in particle sizes, and microplastics with agglomerates were released each time the laser cutter lid was opened and were observed to gradually increase in concentration for a period of at least 20 min after the completion of a cut. The GC-MS gaseous samples primarily contained methyl methacrylate at a low level close to the detection limit of the infrared air analyzer.

Airborne Hexavalent Chromium and Particulate Matter Emissions during the Laser Cutting of Leathers

“…Moreover, when laser cutting the chrome-, veg 1- and oil-tanned leathers, the emission concentration of small-sized range particles (27.4–36.5 nm) was higher than large particles. This trend is consistent with the study investigated by Munoz et al, where the highest particle emission concentrations during laser cutting of acrylic plastics were observed within the range of 27.4–36.4 nm . Although different in the laser’s targeted materials, both studies identified the highest concentrations in the same size range, namely, 27.4–36.5 nm.…”

“…Very few (lower than 3 particles/cm 3 ) particles (>1 μm) were observed when the ventilation was turned on, which indicated the efficiency of the ventilation system because the particle emission concentrations exceeded the upper detection limit of OPS when the ventilation system was turned off. This finding is in concordance with OPS monitoring during the laser cutting of acrylic plastics, where 0.35 μm exhibited the highest distribution . The quoted study set up two OPS devices and two laser cutters at different locations to monitor particle concentrations, simulating an environment resembling a field study that is representative of practical and real-life exposures when operating laser cutters.…”