![]() ![]() For this task it is assumed that 200 g is required to cover a surface area of 500 cm 2. The putty is not applied all at once, but three spraying efforts are assumed to be needed to cover the scratches completely. After completing the task the subject will leave the garage, making the total exposure duration half an hour. The volume of the room is 34 m 3 and the ventilation rate 1.5 h −1. This kind of task is generally not conducted inside the house, but more often in a garage, so the parameters from the General Fact Sheet for a garage are used. The default scenario described for putty from spray is removal of the scratches on a metal surface before the surface is re-painted: in this case, restoring a kettle to its natural state. The dermal contact area is assumed to be 22 cm 2. The dermal load is estimated at 0.2 g which is 0.1% (assumption) of the total product amount. The dermal exposure scenario is similar to the dermal exposure scenario for filler/putty from tubes. Hence, a part of the product is not spread out over a surface.ĭermal exposure can occur due to spills. The surface area during application is lower than during mixing and loading, because the product is used to fill up holes. The surface from which the chemicals can evaporate is estimated to be 50 cm 2 (5 × 10 cm 2). The model selected here is exposure to vapour: evaporation from constant area. During that time inhalatory exposure may occur from the volatile components present such as benzyl alcohol. The exposure duration is set at 240 minutes by default. A period of 30 minutes is assumed to be needed to repair the wood. The filler can be smoothened with the filling-knife. The mixed product is then applied with the filling-knife in to the hole until it is filled completely. ![]() The amount of filler that comes into contact with the skin is estimated to be 50 mg (personal judgment).īefore mixing the components together the decayed wood has to be removed and the surface cleaned properly. As default, 5% of one hand will be exposed during application (equal to 22 cm 2). Dermal exposure is expected to be small, because of the easy application method. It is estimated that this DIY task will require 40 grams to fill the holes. This is estimated at 5 cm 2 per screw hole, assuming 40 screw holes a total surface area of 200 cm 2 is provided. The surface area is determined by summing each cover of a screw hole. The scenario chosen for inhalation exposure is exposure to vapour: evaporation from an increasing area, because the evaporation is related to the surface area. The hole is filled in this way and filler/putty smoothened where application is uneven. The product is then applied to the small gap or hole and smeared over it. The filler or putty is put from the tube on to the filling-knife. The task is expected to occur with a frequency of three times a year. ![]() Assuming that the subject stays in the room for 4 hours in total, the exposure duration will be 4 hours. The default chosen for application was 20 minutes. One of the longest observation times was for filling the holes in a wooden drawer. Application durations varying from 1 minute to nearly 20 minutes were observed. Magré conducted observations of subjects using fillers or putty for their DIY task. No room is specified for this task, therefore the parameters for a non-specified room are used here room volume is 20 m 3 and ventilation rate is 0.6 h −1 according to the General Fact Sheet. Here, the treatment with filler of screw-holes of an entire bookcase is considered before it is painted. This is not a large number, indicating that the product is not used that often.ĥ.3.1. In the UK approximately 800 kg of wood filler is sold per year according to information from EU RAR on bisphenol A (2003). Liquid wood is different from the lacquer and water based fillers/putties, because it is available in different wood colours. ![]() Furthermore, the products can be applied indoors, or both indoors and outdoors. The application of these products is rather superficial and should not be used for depths over 1 cm. These fillers are mainly used to repair little scratches and fill (screw) holes in wood to prepare the materials for another DIY task such as painting. The fillers and putties from tubes include the water based fillers/putties, lacquer based fillers/putties and liquid wood. The two-component fillers will be discussed in section 5.4. The products are ready to use or require a mixing and loading process the two-component fillers. The fillers and putties from tubes are generally used for shallow holes and gaps. ![]()
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