Composition
Fillers and putty are DIY products which are used to remove unevenness from surfaces. The fillers are generally used to fill gaps and holes in walls and wood (often decayed wood). Putty is used to smooth relatively small uneven surfaces caused by screw holes, scratches or coarse materials. The DIY tasks can be very specific. For these specific purposes there are several fillers and putties available on the consumer market. There are general powder based fillers, ready-to-use large hole fillers, fillers and putty in tubes, two-component filler, and spray putty. An overview of available fillers and putty is presented in Table 16 with their compositions and application.
Table 16
Composition of different types of fillers is listed below (based on information from Terwoert et al.[31], supplemented with product information).
A default scenario is described for each of the above mentioned types of filler or putty, because exposure and exposure conditions may differ during mixing and loading, during application, and in the magnitude of the task at hand.
5.1. General filler from powder
Use
The general fillers are used for the filling of holes and cracks with a maximum depth of 5 cm. Furthermore, the filler can be used to set corners when a new wall is constructed. The general fillers are powders, which have to be mixed and loaded with water in ratio of 2:1 (powder: water). As soon as a lump-free paste is obtained the filler can be applied in the hole with a filling-knife. This step is repeated until the hole is completely filled and can be smoothened with the filling-knife. These fillers are suitable for indoor use (some are also suitable for outdoor use) and can be painted with all kinds of paints according to the product information.
5.1.1. Scenario general filler from powder
The filling of small holes in a wall is described here. It is difficult to determine the amount of powder needed to fill those holes, because that is heavily dependent on the depth and size of the holes. Here it is assumed that 250 g of powder is suspended in water to fill the holes in the wall. The task is performed in a non-specified room. Using the parameters for this room for the General Fact Sheet[3] provides a room volume of 20 m3 and a ventilation rate of 0.6 h−1. Performing this task will not occur that often. Twice a year is assumed for the default scenario.
Mixing and loading: general filler from powder
For the mixing and loading of powders please refer to the scenario described in subsection 2.4.2., No exposure model from ConsExpo could be assigned for inhalatory exposure to powder. Information concerning particle size distribution, airborne fraction, and mass generation is insufficient or lacking and thus another description of the exposure was preferred. The product amount of 250 g is suspended in approximately 125 ml water. The inhalation exposure is 0.3 µg which is calculated by the contact rate of 0.25 µg/min and exposure duration of 1.33 min (see subsection 2.4.2). The dermal exposure can be estimated with the constant rate model, where the surface area, contact rate and release duration are 430 cm2, 0.033 mg/min, and 1.33 min, respectively.
Default mixing and loading: general filler from powder
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 2 year−1 | 1 | Estimate |
| Dermal | |||
| Constant rate | |||
| Surface area | 430 cm2 | 2 | See subsection 2.4.2 |
| Contact rate | 0.033 mg/min | 1 | See subsection 2.4.2 |
| Release duration | 1.33 min | 2 | See subsection 2.4.2 |
Application
After the filler is prepared for use, it is applied to the hole with the filling-knife. This takes approximately 15 minutes. Afterwards the filler hardens by water diffusion and evaporation. When the filler is hardened it can be sanded so that a smooth surface is obtained. Inhalatory exposure is expected to be negligible, because the product does not contain constituents which are likely to evaporate except water. For this reason no inhalatory scenario is proposed. Dermal exposure, however, does occur during application (15 minutes). Filler is spilled on hands, while putting the filler in the hole. The spilled amount will be low, because working with fillers is relatively easy. The dermal load is estimated at 0.25 g, which is 0.1% (estimation) of the total product amount. The surface area is the same as during the mixing and loading process described above: 430 cm2.
Default for the use of general filler from powder
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 2 year−1 | 1 | Estimate |
| Dermal | |||
| Instant application | |||
| Surface area | 430 cm2 | 2 | See above |
| Product amount | 0.25 g | 1 | See above |
| Exposure duration | 15 min | 1 | See above |
5.2. Large hole filler
Use
Large hole fillers are used for gaps and holes that have depths from more than 5 cm up to 10 cm. The large hole fillers are stored in buckets or jars (ready to use) or are made from powders. The product can be used indoor and outdoor and can be painted, also with water based paint.
5.2.1. Scenario large hole fillers
The frequency of use is expected to be less than that for the use of fillers for smaller holes (once a year). Here, filling the gaps in a cement/concrete wall is considered as a starting point. The larger gaps of up to 10 cm depth in a wall require a significant amount, which may easily rise up to 1 kg of filler. Performing the task will not take much more time than for a general filler since large gaps can be filled in few repeated steps.
Mixing and loading
The large hole fillers made from powders require the mixing and loading of the powder with water. The mixing and loading process is similar to the mixing and loading of a general filler (see subsection 5.1.1). No exposure model from ConsExpo could be assigned for inhalatory exposure to powder. Information concerning particle size distribution, airborne fraction and mass generation is insufficient or lacking and thus another description of the exposure was preferred.
The inhalation exposure is 0.3 µg dust which is calculated by the contact rate of 0.25 µg/min and exposure duration of 1.33 min (see section 2.4.2). The dermal exposure can be estimated with the constant rate model where the surface area, contact rate, and release duration are 430 cm2, 0.033 mg/min, and 1.33 min, respectively.
Default mixing and loading: Large hole filler from powder
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 1 year−1 | 1 | Estimate |
| Dermal | |||
| Constant rate | |||
| Surface area | 430 cm2 | 2 | See subsection 2.4.2 |
| Contact rate | 0.033 mg/min | 1 | See subsection 2.4.2 |
| Release duration | 1.33 min | 2 | See subsection 2.4.2 |
Application
The application duration is estimated to be 30 minutes. Inhalatory exposure is negligible, because the constituents are not expected to evaporate. Dermal exposure during application occurs via spills. The dermal load will be higher, because the total product amount is larger compared to normal filling tasks. The dermal load is estimated at 0.5 g. The surface area is assumed to be the surface of one’s fingers which equals to 430 cm2.
Default for large hole fillers
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 1 year−1 | 1 | Estimate |
| Dermal | |||
| Instant application | |||
| Surface area | 430 cm2 | 2 | See above |
| Product amount | 0.5 g | 1 | See above |
| Exposure duration | 30 min | 1 | See above |
5.3. Filler / putty from tubes
Use
The fillers and putties from tubes are generally used for shallow holes and gaps. The products are ready to use or require a mixing and loading process; the two-component fillers. The two-component fillers will be discussed in section 5.4.
The fillers and putties from tubes include the water based fillers/putties, lacquer based fillers/putties and liquid wood. 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 application of these products is rather superficial and should not be used for depths over 1 cm. Furthermore, the products can be applied indoors, or both indoors and outdoors. Liquid wood is different from the lacquer and water based fillers/putties, because it is available in different wood colours. In the UK approximately 800 kg of wood filler is sold per year according to information from EU RAR on bisphenol A (2003)[26]. This is not a large number, indicating that the product is not used that often.
5.3.1. Scenario filler / putty from tubes
Here, the treatment with filler of screw-holes of an entire bookcase is considered before it is painted. No room is specified for this task, therefore the parameters for a non-specified room are used here; room volume is 20 m3 and ventilation rate is 0.6 h−1 according to the General Fact Sheet[3]. Magré[6] conducted observations of subjects using fillers or putty for their DIY task. Application durations varying from 1 minute to nearly 20 minutes were observed. One of the longest observation times was for filling the holes in a wooden drawer. The default chosen for application was 20 minutes. Assuming that the subject stays in the room for 4 hours in total, the exposure duration will be 4 hours. The task is expected to occur with a frequency of three times a year. The filler or putty is put from the tube on to the filling-knife. The product is then applied to the small gap or hole and smeared over it. The hole is filled in this way and filler/putty smoothened where application is uneven.
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 surface area is determined by summing each cover of a screw hole. This is estimated at 5 cm2 per screw hole, assuming 40 screw holes; a total surface area of 200 cm2 is provided. It is estimated that this DIY task will require 40 grams to fill the holes. Dermal exposure is expected to be small, because of the easy application method. However, spills may occur. As default, 5% of one hand will be exposed during application (equal to 22 cm2). The amount of filler that comes into contact with the skin is estimated to be 50 mg (personal judgment).
Default for fillers/putty from tube
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 3 year−1 | 1 | Estimate |
| Inhalation | |||
| Exposure to vapour: evaporation from increasing area | |||
| Exposure duration | 240 min | 2 | See above |
| Application duration | 20 min | 2 | See above |
| Product amount | 40 g | 1 | See above |
| Room volume | 20 m3 | 3 | [3] |
| Ventilation rate | 0.6 h−1 | 3 | [3] |
| Release area | 200 cm2 | 1 | See above |
| Temperature | 20 °C | 4 | Room temperature |
| Mass transfer rate | Langmuir | See section 2.7 | |
| Mol. Weight Matrix | 3000 g/mol | 3 | See section 3.1 |
| Dermal | |||
| Instant application | |||
| Surface area | 22 cm2 | 3 | See above |
| Product amount | 0.05 g | 2 | See above |
5.4. Two-component filler
Use
Two-component fillers are used to repair decayed wood (wood decay fillers), stone, polyester, or steel (extra strong filler). These products are required to be very strong, water resistant and capable of stopping further decay (wood decay filler). The two components are mixed in a ratio of 1:1. The two-component filler consists of a resin and a siccative (2-4% volume percentage); otherwise the filler will not harden properly.
5.4.1. Scenario two-component filler
Repairing all spots in the decayed wood of a window frame is considered here. It is assumed that a total of 200 g filler is used to fill the holes and gaps after the decayed wood has been removed. This task can be conducted in every room. A non-specified room with a volume of 20 m3 and ventilation rate of 0.6 h−1, with parameters from General Fact Sheet[3] is considered. The use of two-component fillers is not expected to be frequent (twice a year is assumed).
Mixing and loading: two-component filler
For the default scenario of mixing and loading of two-components please refer to subsection 2.4.1. The two components can be put on the filling-knife and mixed according to product instructions. An equal amount of 100 g is taken from the two components. The two components are mixed (surface area 100 cm2) with help of a tool (another filling-knife or spatula) until a hom*ogenous colour is obtained. During the mixing and loading, inhalatory exposure may occur. The exposure to vapour: evaporation model is selected. The mixing and loading process is estimated to take five minutes. Dermal exposure is not expected to be high because of the use of tools and relative low product amount. The dermal load is therefore estimated to be 20 mg.
Default mixing and loading: two-component filler
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 2 year−1 | 1 | Estimate |
| Inhalation | |||
| Exposure to vapour: evaporation constant release area | |||
| Exposure duration | 5 min | 1 | See above |
| Application duration | 5 min | 1 | See above |
| Product amount | 200 g | 1 | See above |
| Room volume | 1 m3 | 1 | See subsection 2.4.1 |
| Ventilation rate | 0.6 h−1 | 1 | See subsection 2.4.1 |
| Release area | 100 cm2 | 1 | See above |
| Temperature | 20 °C | 4 | Room temperature |
| Mass transfer rate | Langmuir | See section 2.7 | |
| Mol. Weight Matrix | 3000 g/mol | 3 | See section 3.1 |
| Dermal | |||
| Instant application | |||
| Surface area | 2 cm2 | 3 | See subsection 2.4.1 |
| Product amount | 20 mg | 1 | See above |
Application
Before mixing the components together the decayed wood has to be removed and the surface cleaned properly. The mixed product is then applied with the filling-knife in to the hole until it is filled completely. The filler can be smoothened with the filling-knife. The application duration is not long. A period of 30 minutes is assumed to be needed to repair the wood. The exposure duration is set at 240 minutes by default. During that time inhalatory exposure may occur from the volatile components present such as benzyl alcohol. The model selected here is exposure to vapour: evaporation from constant area. The surface from which the chemicals can evaporate is estimated to be 50 cm2 (5 × 10 cm2). The surface area during application is lower than during mixing and loading, because the product is used to fill up holes. Hence, a part of the product is not spread out over a surface.
Dermal exposure can occur due to spills. The dermal exposure scenario is similar to the dermal exposure scenario for filler/putty from tubes. The dermal load is estimated at 0.2 g which is 0.1% (assumption) of the total product amount. The dermal contact area is assumed to be 22 cm2.
Default for two-component filler
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 2 year−1 | 1 | Estimate |
| Inhalation | |||
| Exposure to vapour: evaporation from increasing area | |||
| Exposure duration | 240 min | 2 | See above |
| Application duration | 30 min | 2 | See above |
| Product amount | 200 g | 1 | See above |
| Room volume | 20 m3 | 3 | [3] |
| Ventilation rate | 0.6 h−1 | 3 | [3] |
| Release area | 50 cm2 | 1 | See above |
| Temperature | 20 °C | 4 | Room temperature |
| Mass transfer rate | Langmuir | See section 2.7 | |
| Mol. Weight Matrix | 3000 g/mol | 3 | See section 3.1 |
| Dermal | |||
| Instant application | |||
| Surface area | 22 cm2 | 3 | See above |
| Product amount | 0.2 g | 2 | See above |
5.5. Putty from spray
Use
Putty from spray is generally used for very small scratches on wood and metal. The spray produces a superficial layer which fills even the smallest scratches. For this reason, the product can be used to finish a task using fillers from tubes or powders. The product is a common asset in automobile and paint shops. Generally, a thick layer is sprayed onto the surface. Special equipment is required to shave and polish the treated surface into form before a paint job. Therefore, this product is generally used by professionals. This scenario, however, is described for non-professional users.
5.5.1. Scenario putty from spray
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. 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[3] for a garage are used. The volume of the room is 34 m3 and the ventilation rate 1.5 h−1. After completing the task the subject will leave the garage, making the total exposure duration half an hour.
The putty is not applied all at once, but three spraying efforts are assumed to be needed to cover the scratches completely. For this task it is assumed that 200 g is required to cover a surface area of 500 cm2. A mass generation rate of 1.5 g/sec provides spray duration of 135 seconds (rounded off number; 3x spraying to cover the scratches provides a spraying duration of 45 seconds). The weight fraction of non-volatiles is estimated to be 30%, twice as high as for glue spray, because it is assumed that putty requires a higher percentage of solids. Dermal exposure can be estimated with the constant rate model. The exposed dermal area will be the surface of both hands (860 cm2 according to the General Fact Sheet).
Default for putty spray
| Default value | Q | Reference, comments | |
|---|---|---|---|
| General | |||
| Frequency | 1 year−1 | 1 | Estimate |
| Inhalation | |||
| Exposure, spray model | |||
| Spray duration | 135 sec | 2 | See above |
| Exposure duration | 30 min | 2 | See above |
| Room volume | 34 m3 | 3 | Garage [3] |
| Room height | 2.5 m | 4 | Standard room height |
| Ventilation rate | 1.5 h−1 | 3 | Garage [3] |
| Mass generation rate | 1.5 g/sec | 3 | See subsection 2.3.3 |
| Airborne fraction | 1 g/g | 3 | See subsection 2.3.3 |
| Weight fraction non-volatile | 0.3 | 1 | See above |
| Density non-volatile | 1.3 g/cm3 | 3 | See subsection 2.3.2 |
| Initial droplet distribution – median (C.V.) | 40 µm (0.4) | 3 | See subsection 2.3.3 |
| Inhalation cut-off diameter | 15 µm | 3 | See subsection 2.3.3 |
| Dermal | |||
| Constant rate | |||
| Surface area | 860 cm2 | 2 | See above |
| Contact rate | 100 mg/min | 2 | See subsection 2.3.4 |
| Release duration | 135 sec (45 sec * 3) | 2 | See above |
