Table 1.
Work tasks performed at the two companies, types of engineering controls and types of personal protective equipment (PPE).
| Work task number | Work task | Work task description | Location/ Engineering controls | PPE |
|---|---|---|---|---|
| Study A | ||||
| A1 | Preparation of graphene nanoplatelets ink (weighing, mixing). Note that this is not the same ink printed with in A3! | Weighing of graphene nanoplatelet powder, addition of liquid and mixing. | Chemistry laboratory/Fume hood | Half-face respirator (A + P3), lab coat, protective gloves of nitrile, goggles |
| A2—day 1 | Preparation of titanium dioxide nanoparticle ink (weighing, mixing) | Weighing of titanium dioxide nanoparticle powder, weighting of liquid. Addition of powder by sieving into the liquid and mixing. | ||
| A2—day 2 | Preparation of titanium dioxide nanoparticle ink (weighing, mixing) | |||
| A3 | Screen printing with graphene ink (HDPlas Graphene Ink), 10 sheets | Transfer of ink to the screen printer, start of printing process and a number of sheets was printed. The printed sheets were placed in the drying oven. After the printing process the ink was removed and the screen printer and its equipment was cleaned. | Printing laboratory/process ventilation | Clean room lab coat, hair net, protective gloves of nitrile |
| A4 | Screen printing with carbon black ink (C740), 10 sheets | |||
| A5 | Screen printing with carbon black ink (CXT0641), 10 sheets | |||
| A6—day 1 | Screen printing with carbon black ink (C7102), 20 sheets | |||
| A6—day 2 | Screen printing with carbon black ink (C7102), 22 sheets | |||
| A7 | Screen printing with copper ink (CP-PLS-010715-R1A), 10 sheets | |||
| Study B | ||||
| B1 | Preparation of graphene oxide coating (weighing, mixing) | Weighing of graphene powder, addition of liquid to the powder and mixing. Transferring of the liquid to another container followed by addition of glass beads and more mixing. Finally, 2 steps of filtration of the liquid to remove the glass beads. | Chemistry laboratory/Parts in open fume hood (weighing, mixing), parts on open bench (filtration steps) | Half-face respirator (A + P3), lab coat, protective gloves of nitrile, goggles |
| B2 | Spraying and curing graphene oxide coating, and cleaning/washing up after | Transfer of the liquid coating to a paint sprayer, cleaning of metal plates, paint spraying of metal plates, placing the coated plates in a furnace. Cleaning of paint sprayer in the spray booth followed by washing up mixing equipment in the fume hood and at the sink. | Test laboratory/parts in spray booth, parts in open fume hood and sink (cleaning and washing up) | |
| B3 | Abrasion test with a metal brush on graphene oxide coating | The coated plate was placed in the abrasion testing equipment. A brush, rotated with a certain speed, was placed to have contact with the plate. When the surface was abraded the test was ended. | Test laboratory/none | Laboratory coat, protective gloves of nitrile, goggles |
| B4 | Abrasion test with a nylon brush on graphene oxide coating | |||
| B5 | Preparation of titanium dioxide nanofiber coating (weighing, mixing) | Weighing of titanium dioxide nanofiber powder, addition of liquid to the powder and mixing. Transferring of the liquid to another container followed by addition of glass beads and more mixing. Finally, 2 steps of filtration of the liquid to remove the glass beads. | Chemistry laboratory/parts in open fume hood (weighing, mixing), parts on open bench (filtration steps) | Half-face respirator (A + P3), lab coat, protective gloves of nitrile, goggles |
| B6 | Spraying and curing titanium dioxide nanofiber coating, and cleaning/washing up after | Transfer of the liquid coating to a paint sprayer, cleaning of metal plates, paint spraying of metal plates, placing the coated plates in a furnace. Cleaning of paint sprayer in the spray booth followed by washing up mixing equipment in the fume hood and at the sink. | Test laboratory/parts in spray booth, parts in open fume hood and sink (cleaning and washing up) | |
| B7 | Abrasion test with a metal brush on titanium dioxide nanofiber coating | The coated plate was placed in the abrasion testing equipment. A brush, rotated with a certain speed, was placed to have contact with the plate. When the surface was abraded the test was ended. | Test laboratory/None | Laboratory coat, protective gloves of nitrile, goggles |
| B8 | Abrasion test with a nylon brush on titanium dioxide nanofiber coating | |||