Summary and conclusions, Miljøstyrelsen

Vurdering af malings miljøbelastning i anvendelsesfasen

Summary and conclusions

Depending on the situation, different amounts of waste of paint have been recorded for painting jobs as well as for the amount of paint that remains in the paint pots. During the preparation of the criteria for the EU eco-label it was estimated that the amount of paint remaining in the paint pots was approximately 30% of the amount of paint applied to the surface. It is emphasized that there is no information about the amount of wasted paint when the paint tools are cleaned. (European eco-label, Project for application to Paint and Varnishes, Volume 5 Results of the extension phase, The Life Cycle Analysis of eleven indoors decorative paints, ECOBILAN 1993). Other surveys, though, estimate the amount of wasted paint to be 5%. The common issue in all of the surveys is that the amounts of wasted paint are estimated, and in practice the total waste during a paint job has been unknown.

The purpose of this project is to quantify the volume of the waste of paint that is connected to painting jobs. Another purpose is to assess the environmental impact resulting from the waste that occurs during application of the paint, during cleaning of paint brushes, rollers and other paint tools, and during the disposal of polluted covering materials and remaining paint etc. The study covers both private and professional painters.

At first a detailed survey on private painters is carried out, determining the size of the various kinds of waste that occur during the paint jobs and in the paint tools. In the light of this survey it is possible to estimate the total waste of paint during a paint job. The survey is made by weighing the paint tools and the covering materials before and after the paint job.

The following items are included in the survey of the waste of paint during paint jobs:

	Painting an indoor wall with water-based interior paints (by using a paintbrush, a paint roller and a paint pad system).
	Painting a wooden wall, a fence and an overhang with wood primer and water-based wood preservatives (by using a paintbrush).
	Painting a wooden wall and a fence with alkyd-based paint (by using a paintbrush).

The basis of the survey was the different operations during the work, e.g. stirring and pouring the paint, measuring the droppings of paint on the covering material, and the remaining paint in the paint tools before they are cleaned.

In the light of the detailed survey relating to private painters, preferred numbers have been made for the waste of paint in different situations and for different types of tools like paintbrushes, paint rollers and paint pads in various sizes. In order to get an idea of the amount of waste of paint and of the remains of paint in the different paint jobs, six scenarios were drawn up on the basis of the preferred numbers for waste of paint in different situations. The scenarios show that the amount of waste varies considerably depending on the purchase of paint, the paint job, the use of different types of paint tools and the personal behaviour during the paint job.

The calculations show that the largest waste at the completion of a private painter’s job is the paint remaining in the paint pots. This paint is most likely going to end up as waste later on, and according to the scenarios it may account for up to 60% of the purchased amount of paint. When we look at larger paint jobs, we see that the remaining paint accounts for 7-8% of the purchased amount of paint. The quantity of the remaining paint, however, depends on a number of conditions, e.g.:

	The possible sizes of the paint pots.
	The price of the various sizes of the paint pots.
	If the area that is going to be painted has been calculated beforehand.
	The structure of the surface.
	The person that paints.
	The size of the paint job etc.

The calculations of the waste of paint also show that the actual waste (spillage on covering material, remaining paint in the tools etc.) from paint jobs typically accounts for between 8 and 30% of the purchased amount of paint. The waste depends on many aspects, such as:

The choice of paint tools (paint rollers cause more waste than paintbrushes).

The scope of the paint job.

The person that paints.

The number of persons painting etc.

Thus, the total waste (including the remaining paint in the paint pots at the end of the paint job) calculated in the scenarios, accounts for between 12 and 65% of the purchased amount of paint.

The following items show the possibilities of getting rid of the garbage:

To the water-phase via the drain/sewer.

To the ground via spilling (outdoor painting without covering material).

As waste either to ordinary municipal waste combustion plants via the household waste or to incineration plants (Kommunekemi) via recycling units.

Today, you have to deposit your paint remains at a local recycling unit or at the paint dealers. In addition, there will always be a waste of paint to the water phase when you clean the tools and a waste from the covering material etc., which will probably be incinerated along with the ordinary household waste.

It appears that the largest spillage of paint is to the waste phase partly because of the relatively large remains of paint. In most of the waste scenarios the waste disperses as follows:

Between 65 and 97% of the total paint spillage end up as waste.

Between 3 and 35% of the total paint spillage end up in the sewer.

Regarding outdoor paint jobs without any covering material there will be a spillage to the ground, though, at approximately 1% of the total spillage of paint.

The calculations also show that it is possible to move as much as approximately half the waste from the paint tools from the water phase to the waste phase by changing some of the routines in the work, such as wrapping the paint roller trays in plastic bags and wiping off the tools in the covering material before cleaning it.

Beside the survey on the private painters, a survey has been made on professional painters’ routines. This survey shows that professional painters do work with waste reducing routines such as wrapping the paint tools in plastic bags until it is used again the next day. The majority of the professionals never wash their paint rollers. They throw them away after they have finished the job. In addition, it is possible for the professional painters to use the remains of paint on other jobs, which in general makes their amount of waste much smaller than that found for private painters’.

Thus, the survey shows that whether you are a private or a professional painter you have a fairly big influence on the size of the amount of waste and on what happens to it – whether it ends up as garbage, in the sewer or on the ground. Therefore, the recommendations will depend on the assessment of the environmental impact of the paint to water, to the ground and when it is treated as waste.

The environmental assessments of the waste of paint to the waste-phase, the water-phase and to the ground show that generally the most appropriate thing to do is to treat the wasted paint at an incineration plant which is built to deal with chemical waste – in other words at Kommunekemi today (primo 2000). Similar to other kinds of waste, the paint might contribute to the formation of dioxin and because of the contents of heavy metals it will contribute to the pollution with heavy metals too. Laboratory tests as well as toxicological data from the literature show that paint may contain substances, which are unwanted in both the aquatic and terrestrial environment. Laboratory tests show that water-based paints have the least impact on organisms living in both aquatic and terrestrial surroundings whereas water-based wood preservatives and - especially - paints based on organic solvents have a far bigger impact on the aquatic and terrestrial environment and their organisms.

Tests of brush cleaner show that it may have a huge impact on the water environment when it is discharged into the sewer. Therefore, any leftover should not be discharged into the sewer but rather be delivered at the local recycling unit.

We therefore recommend that the amount of waste of paint in general is minimised by buying the correct quantity of paint e.g. by calculating the area being painted before you buy the paint. In addition, it is recommended that the paint tools and the paint roller trays are wrapped in plastic bags from day to day in order to avoid cleaning the tools too often.

It is also recommended that paint roller trays are wrapped in plastic bags before the paint is poured in order to move the waste of paint from the water phase to the waste phase. Wiping off the paint tools in the covering material before cleaning it is also going to move part of the waste of paint from the water phase to the waste phase.

Finally, we recommend minimising the discharge of waste of paint to the water phase by cleaning in batches. If you use brush cleaner or white spirit when you paint with paint based on organic solvents it is under no circumstances allowed to discharge the cleaner into the sewer – instead you must hand it in at the local recycling unit.

Recommendations

The project makes a series of recommendations on planning a paint job, buying and using paint as well as on cleaning the paint tools and storing the paint. Below, the recommendations on paint based on organic solvents are listed. Chapter 11 contains all the recommendations.

Planning and purchase

1.

Measure the area you are going to paint - the measurement should be in whole centimetres. Calculate the area in half m². Write down the measures and bring them to the shop when you buy the paint, thus avoiding buying too much paint.

2.

If possible, buy water-based paint instead of paint based on organic solvents. Buy water-based paint without content of organic solvents or with a content as small as possible. Buy products with a code number as low as possible considering the quality of the paint.

3.

Avoid the situation where you have to buy more paint – you should rather buy a little too much than a little too little from the beginning. If necessary you may supplement the requisite quantity of paint by a small paint pot in which you may later store the possible leftover of paint. If you are short of just a small quantity of paint it is possible, though, to make the paint go further by thinning it.

4.

Plan the job in a way that enables you to do it in larger "segments". Paint as much as possible every time the paint tools are in use.

Use

Always cover the ground when you paint outdoors.

Minimise the waste when you paint.

	Scrape off the paint from the lid on the rim of the paint pot when it is opened.
	When you pour the paint into the intermediate container or paint roller tray scrape the drips from the vertical outside and from the rim of the paint pot back into the pot. It is also possible to wipe off the drip with the paintbrush.
	Paint as much as possible each time the paint tools are in use.
	Wrap the paint tools and any leftover of paint (in intermediate container) in plastic bags for the next day.
	After stirring the paint wipe off the stick with a paintbrush or scrape it off on the rim of the paint pot.

Minimise discharge to the sewage of leftover paint.

	Put a plastic bag around the paint roller tray and pour the paint directly on the plastic bag.
	Wrap the paint rollers in plastic bags for the next day without cleaning them, thus reducing the waste and the discharge to the sewage considerably.
	Put the paint brushes in water for the next day (or wrap them in plastic bags) without cleaning them. This way you avoid unnecessary discharge to the sewage.

Avoid running out of paint.

If it looks like you are running out of paint it is possible to thin the paint with the relevant solvent in order to make it go further. It is only possible, though, if you are short of a small quantity of paint. Estimate your consumption when you are halfway through the job.

Prolong the life of the paint.

Avoid dipping the paintbrush directly in the paint pot if you are going to save the paint. Use a intermediate container.

Cleaning, disposal and storing of paint based on organic solvents.

1.

If you are going to save the paint tools:

Clean it in a container in batches. This causes the least consumption of cleaner. Use approx. ½ litre for a paint roller and approx. 1 decilitre for a paintbrush for each cleaning. Clean with a new portion of cleaner until you reach the wanted cleanness.

Use a suitable cleaner e.g. white spirit.

Pour the cleaner from the first and second cleaning into another container and let the paint settle. Pour out the upper fluid and save it in a closed container until the next time you are going to paint. Hand in the discharge in a closed container at the recycling unit. The leftover of paint or the leftover of cleaner or white spirit are under no circumstances allowed in the sewer. It must be handed in at the recycling unit.

After you have cleaned with cleaner or white spirit you rinse the paint tools with water and soap in a container. Because of leftover white spirit/cleaner in the first portion of the rinsing water you must hand it in at the recycling unit too.

2.

If you want to throw away your paint tools throw it away without cleaning it first. Wrap it in a plastic bag and hand it in at the recycling unit along with the potential leftover of paint.

3.

Pour what is left of the paint back into the container if you poured too much into the intermediate container or paint roller tray.

4.

Remove the paint that is sitting on the inside of the lid before the paint is put away. By doing this you prevent dried paint flakes from the lid from falling into the paint. This prolongs the life of the paint.

5.

If you have any paint left in a container to be discharged, it must be handed in at the local recycling unit or at the paint dealer where it is bought.