How to Calculate VOC's in Paint

If your paint shop produces more than five tonnes of volatile organic solvent (VOC) emissions in any 12-month period, you are required to comply with Part I of the Environmental Protection Act (EPA) 1990.

Check out our water based video for more info on VOC's

This means that you must:

Obtain a permit to operate the coatings process.
Comply with the conditions contained in the relevant Secretary of State's Process Guidance (PG) Notes.

It's therefore imperative that you keep accurate records of your day-to-day VOC consumption.

NOTE: If you are using non-exempt thinners with your coatings, you will need to account for these in your calculations. Also, remember that most water-based paints have VOC emissions that need to be calculated as well as solvent-based paints.

This article will show you how to calculate VOC in paint using the mixing ratio methods.

METHOD 1: Using the mix ratio

This calculation is useful if you always mix a coating from the same components, in the same ratio, but perhaps use different amounts of the coating for different tasks. It provides a quick method for working out the VOC emissions for each quantity of the mixed paint that you use. You will need the following information for the calculation:

VOC of material (expressed in g/litre) - you can find this on the product data sheet or material safety data sheet (MSDS). It may be listed under 'Physical Properties' or VOCs may have their own section on the data sheet. VOC of material is also sometimes referred to as 'VOCs', 'Actual VOC', 'Total VOC', or 'Emitted VOC'.

See example below:

Mix ratio (expressed in parts) - to find the overall VOC emissions from the coating.

The calculation:

VOC of material X ratio for each component part	= VOC emissions
Total number of component parts

Working example: Imagine you have a coating made up of the following components:

	BASE COAT:	REDUCER:	CATALYST:
VOC OF MATERIAL:	400 g/litre	300 g/litre	500 g/litre
MIX RATIO:	3	2	1

The calculation would look like this:

(400 x 3) + (300 x 2) + (500 x 1)

1200 + 600 + 500

2300

= 383.33 g/litre total VOC of mixture 3 + 2 + 1 6 6 You can then work out the VOC emissions for each quantity of the mixed paint that you use. For example: Paint job 1: Amount used = 2 litres Paint job 2: Amount used = 10 litres Paint job 3: Amount used = 5 litres The calculation will be:

Total VOC of mixture X amount used = VOCs emitted for the paint job

So, for each paint job using the same mix, the VOC emissions would be: Paint job 1: 383.33 g x 2 litre = 766.66 g VOC emissions Paint job 2: 383.33 g x 10 litres = 3833.30 g VOC emissions Paint job 3: 383.33 g x 5 litres = 1916.35 g VOC emissions

Method 2:

This calculation applies for all other situations, i.e. where you are unable to work with a consistent mix ratio. You will need the following information for every component that you use in a coating:

VOC of material (expressed in g/litre)
Total Volume of Coating Applied (expressed in litres) - you will need a recordkeeping system for recording this.

The calculation:

VOC of material x amount used = VOC emissions for the component
Sum of VOCs for components = total VOC

Working example: Imagine you have a coating made up of the following components:

	BASE COAT:	REDUCER:	CATALYST:
VOC OF MATERIAL:	400 g/litre	300 g/litre	500 g/litre
AMOUNT USED:	10 litres	7 litres	5 litres

Basecoat VOC emissions: 400 g/litre x 10 litres = 4000 g Reducer VOC emissions: 300 g/litre x 7 litres = 2100 g Catalyst VOC emissions: 500 g/litre x 5 litres = 2500 g Total VOC emissions for mixed coating: 4000 g + 2100 g + 2500 g = 8600 g.

How to calculate annual VOC emissions

To determine the amount of VOCs that you generate per year in tonnes:

Step 1:

Total number grams of VOCs that you have generated across the year	= Annual VOC emissions in kg
1000

Step 2:

Total number KG of VOCs that you have generated across the year	= Annual VOC emissions in tonnes
1000

Working examp le: If you generated 3200000 g of VOCs through your total annual paint consumption, the calculation would be: Step 1:

3200000 g	= 3200 kg of VOC emissions per year
1000

Step 2:

3200 kg	= 3.2 tonnes of VOC emissions per year
1000

How can Ultrimax help you to keep track of your VOCs?

One of the best ways to ensure that you stay compliant with VOC Regulations is to obtain a monthly VOC report from your paint supplier. At Ultrimax, we supply our customers with the VOC figures for your order in every invoice. We can also save your team time and resources by sending you a monthly VOC report.

DOWNLOAD GUIDE [link to downloadable PDF]

DOWNLOAD OUR VOC GUIDE Find out about the solutions available for reducing VOC emissions in your paint shop.

If you are interested in finding out more about how Ultrimax can help you to monitor and control your VOCs, call us on 01302 856666 or email sales@ultrimaxcoatings.co.uk

Need More Help Calculating VOC Free Paint?

If you can’t find a fix for the issue you’re experiencing or you need more advice, drop us a line and we’ll get your paint job on track.