VOC Regulations and Using Water-Based Coatings, Paints and Adhesives

Volatile organic compounds (VOC) present multiple issues for the environment and for businesses that must control their use. Due to the hazardous nature of these compounds, several agencies place them under strict regulations. However, methods used in the past to mitigate these compounds compromised the performance of the paints or adhesives. Consequently, users increased their use of VOC-containing compounds to get better results for their products.

Today, with modern materials, VOC reduction can benefit both your business and the environment. New materials and formulation methods can reduce the VOCs in paints or adhesives while maintaining their performance. When formulating products, consider using methods to create low VOC coatings or adhesives to maintain regulatory compliance and prepare your paints, sealants or adhesives for a greener future.

What Are VOCs?

To understand VOCs, you must distinguish these compounds from other related products. Hazardous Air Pollutants (HAPs) are products that have the potential for causing cancer or other serious health issues. Within the 187 HAPs identified by the Environmental Protection Agency (EPA), many are also volatile organic compounds.

Volatile organic compounds have low water solubility and high vapor pressure, allowing their release as gases into the air. Thousands of products use VOCs in their creation, including dry cleaning fluids, petroleum fuels, paints, adhesives, sealants, hydraulic fluids and paint thinners.

While many HAPs impact air inside and out, VOCs typically produce problems for indoor air quality. Inside, VOC levels can be up to 10 times higher than outside. Consequently, controlling VOCs in paints, adhesives and similar substances for inside use can improve indoor air quality
and health.

Some substances are exempt from regulations for VOCs because they are not as reactive. Definitions of VOCs depend on the country, and the United States’ list of exempted products include:

  • Acetone
  • AMP-95 (2-amino-2-methyl-1-propanol)
  • Dimethyl carbonate
  • Methyl acetate
  • Methyl chloride
  • Oxol 100 (parachlorobenzotrifluoride)
  • Propylene carbonate
  • T-butyl acetate

Different countries or regions have their definitions and means of monitoring VOCs. Often health or environmental agencies regulate the output of these products.

In Canada, Health Canada defines VOCs as organic compounds that can negatively impact air quality and have boiling points ranging from 50 to 250 degrees Celsius (122 to 482 degrees Fahrenheit).

The Chinese EEP defines VOCs in China as products that come from fuel burning, oil storage and transportation, furniture coatings, cooking oil fumes and other chemicals from civilian use, using automobiles and industrial production.

The European Union’s (EU) VOC Solvents Emissions Directive REACH similarly identifies VOCs as Canada does, based on the boiling point. In the EU, VOCs are organic compounds with boiling points lower than 250 degrees C (482 degrees F) when measured at regular atmospheric pressure, 101.3 kPa.

India’s Central Pollution Control Board does not differentiate VOCs as a category. However, it does monitor nitrogen oxides (NOx), fine particulate matter (PM10), suspended particulate matter (SPM) and sulfur dioxide (SO2).

The United States also has regulations involving VOCs. However, the specific guidelines that companies must follow depend on their location. For instance, products made or sold in California must meet that state’s requirements in addition to federal regulations.

VOC Regulations for Paint

Several bodies in the United States regulate VOCs. These include the EPA, the Occupational Safety and Health Administration (OSHA) and ASTM. Many states have additional regulations for VOCs, such as California’s Prop 65. These regulators have separate requirements for controlling
VOC levels in different situations and for varying reasons. For instance, the EPA concerns itself with the environmental impacts of VOCs, while OSHA wants to protect employees exposed to these compounds. Which agencies and regulations a product or company must follow depends on the situation.

EPA Requirements

The EPA’s focus on regulating VOCs comes from their ability to generate photochemical smog when they react with nitrogen oxides and sunlight. The requirements for VOC levels and control are outlined in 40 CFR 59. This regulation separates various requirements for consumer products, architectural coatings, automobile refinish coatings, aerosol coatings and fuel containers. Legal guidelines within each category outline how producers must keep records, labels and reports on the VOCs in their products.

OSHA Regulations

OSHA protects worker health for those in office buildings, manufacturing facilities and everywhere else. By regulating levels of VOCs that workers have exposure to, the agency prevents short and long-term health problems caused by these substances. OSHA publishes tables of permissible exposure limits of VOCs and other substances that compare its requirements to those of other agencies. These tables serve as a good reference for anyone seeking compliance with OSHA and other regulatory agencies.

ASTM D6886

Once known as the American Society for Testing and Materials, ASTM creates technical standards used in the United States and worldwide. These voluntary standards cover processes, products, services and materials, including VOCs.

The standard governing testing of VOCs in water-based coatings is the ASTM D6886. Unlike other standards, this one only describes how to test for VOCs in paints and other coatings. By using this method, companies can determine whether their products fall within other agency regulations.

California Prop 65

California Proposition 65, passed in 1986, does not prohibit VOCs or regulate their acceptable levels. This law requires products containing any chemicals known to cause birth defects or cancer to warn those exposed to the chemicals. Warnings can take the form of labels, workplace signs or newspaper notices. The state maintains a listing of more than 800 chemicals that require the label if a product contains them. This list includes VOCs and other hazardous compounds.

United States Green Building Council

The United States Green Building Council creates requirements for VOC limits in green building construction projects. The organization outlines VOC limits for sealants, adhesives and other substances. Structures that seek Leadership in Energy and Environmental Design (LEED) certification need to follow these guidelines, which promote healthier, more sustainable structures.

Why Is VOC Reduction Important?

Cutting VOCs in paints and other products benefits people in spaces with the products, those applying the products and the environment. Air quality improvements help the environment and individual health. Therefore, products for both indoor and outdoor use can benefit from reducing VOCs.

Preventing Ground-Level Ozone and Smog Creation

VOCs can mix in the atmosphere with sunlight, heat and nitrogen oxides to produce ground-level ozone. By reducing the amount of VOCs in products during formulation and application, ground-level ozone, which is the main component of smog, can drop. Ground-level ozone can cause breathing problems, especially for sensitive individuals or those with asthma. Therefore, reducing ozone makes communities healthier.

Improving Manufacturer Sustainability

Low VOC products are a greener option, improving environmental sustainability for the companies that make them. As many construction companies and their customers seek to create greener buildings to meet LEED guidelines, they have a demand for low VOC bonding adhesive and other building products. Companies that create adhesives, sealants or paints to meet the green standards provide a sustainable supply for environmentally conscious builders.

Avoiding Fines for Exceeding VOC Quotas

Staying compliant with VOC regulations can help companies avoid fines. Not having to pay fines and make corrections in production processes will save money over time and make investing in reducing VOCs worthwhile.

Odor Reduction

VOCs can produce odors that can cause headaches, eye irritations, nose and throat problems, dizziness or memory issues. Lower VOC products can reduce these negative health effects and cut down on odors.

Earning LEED Credits

LEED certification for buildings is a gold standard for sustainability. In fact, among corporate leaders, 61% believe sustainability sets their companies apart and improves their financial performance. Producers of low VOC adhesive or paint used in the construction of LEED buildings can cater to this market.

To obtain LEED certification, building design and construction teams need to earn a specific number of credits based on sustainable materials and practices they use. With low VOC products, builders can earn credits toward their LEED certification.

Planning for Future Regulatory Restrictions

Creating low VOC paint, coatings or adhesives can improve manufacturer competitiveness into the future. As regulatory agencies update their requirements for VOC levels, producers who create low VOC products will remain competitive.

Solvent-Based vs. Water-Based Coatings

When comparing water-based vs. solvent-based paints and coatings, it’s important to look at both their performance and VOC content. Both water-based and solvent-based substances require caution during use and storage because their vapors can be flammable. Solvent-based coatings remain popular for many projects that demand lower costs and faster drying time. However, through precise formulation, some water-based coatings can offer the same benefits as solvent-based paints.  

Solvent-Based Coatings

Solvent-based coatings use a solvent to hasten drying time. The solvent reacts with oxygen to evaporate into the air. While this evaporation releases VOCs, it also allows for drying in humid environments that would prohibit proper drying of water-based paints.

Solvent-based paints also have the advantage of protecting against corrosion on surfaces susceptible to water damage. Consequently, many industrial coatings use solvent bases. Plus, solvent-based products cost less than water-based ones.

Water-Based Coatings

The low VOCs and HAPs of water-based coatings mean they are a greener option than solvent-based paints. Water-based coatings can work well for indoor applications where VOCs can build and cause breathing problems. Many interior paints and adhesives use water for their bases.

The downside to water-based paints is their need for specific humidity levels and temperatures to ensure proper drying. Some high-humidity environments will not allow these paints to correctly dry, leaving the surfaces tacky or the finish uneven.

Though the surfaces on which they are used require preparation to ensure proper adhesion, water-based paints have more applications than powder-based coatings or solvent-based paints. For many, overcoming the minor issues affecting adhesion is an acceptable trade-off for using a greener alternative that helps them to avoid fines for exceeding VOC levels.

Modern chemical engineering allows for water-based paints to have similar benefits that were once only found in solvent-based coatings. For instance, proper engineering can permit water-based paints to have UV resistance, moisture repellence and abrasion resistance.

Difficulties With Powder-Based Coatings

Powder-based coatings are another alternative to liquid solvent or water-based options. Due to the method of application, these coatings are much more efficient. What makes powder coatings different is their solid state. The solid powder, though, requires high temperatures to cure. However, it does not release VOCs as solvent-based paints do.

Several difficulties prohibit the use of these coatings for universal coverage of surfaces. In fact, while powder-based coatings perform very well where appropriate, they have a very limited range in what they can do.

Need Substrates That Can Handle High Temperatures

First, any substrate that has a powder-based coating applied must have the capacity to withstand high temperatures. After the application of the powder, the surface requires heating to melt the powder, which allows it to thermoset into an even layer of color. Temperature-sensitive substrates cannot accommodate the high heat of powder coatings.

Only Permits One Color at a Time

While water-based paints and coatings permit color changing and matching during the application, powder coating requires pre-tinting before application. Plus, powder coating can only apply one color at a time and requires curing between colors. For multicolored surfaces, the time required for powder coating may become prohibitive.

High Financial Requirements for Application  

The most severely constraining issue with powder coating is the investment required for application. While small projects are easily painted with a water-based coating, powder coating requires time, equipment and space that makes small projects not financially feasible. Most facilities that provide powder coating do so for large orders to offset the investment required.

Issues That Affect Water-Based Coating Adhesion

Getting water-based coatings to adhere to surfaces can be difficult due to several issues. However, overcoming these problems can make using water-based paint possible, especially with less porous and harder-to-coat plastics.

Lack of Wetting Agents

Solvents dry faster because the liquid solvents evaporate and leave the pigment adhering tightly to the surface. The chemistry of the solvent wets the surface, which allows the pigmentation to directly contact it.

Water-based coatings, however, create tiny beads of water containing the pigment. These beads don’t dry quickly and suspend the pigments above the surface. To improve the performance of water-based paints, wetting and foaming agents prevent beading and help the pigment to contact the surface.

Using the wrong wetting agents can have issues, though. Improperly matched agents may prevent the full adhesion of the coloring to the surface. Defoaming agents intended to prevent beading can also prevent the coating from creating a smooth surface. Choosing proper agents for wetting and defoaming to pair with the substrate and components of the coating will ensure proper adhesion of the paint while avoiding some of the disadvantages of these additives.

Powdering Out Due to Improper pH

Regulating pH is important for the adhesion of paints and coatings. Formulators may use ammonia to raise the pH of water-based coatings. The downside to this product is the faster evaporation rate of ammonia compared to water. When the ammonia evaporates out of the paint as it dries, the pH of the coating drops. Consequently, the coating may “powder out” due to the excessively low pH. This prevents the coating from properly adhering to the surface.

Water Evaporation and Higher Energy Requirements

Water-based coatings need low humidity and high heat to dry quickly. Solvent-based coatings don’t require special environments to dry properly. Coaters may need additional energy to create the desired warmth and low humidity for the water to evaporate faster. In some cases, bringing in dehumidifiers can increase the energy required, raising the overall total cost.

Needing Surfactants to Overcome Water’s High Surface Tension

Water has high surface tension. The surface tension of any coating needs to be lower than the value of the surface. The problem with water-based coatings is the high surface tension of water. Lower surface tensions allow for better dispersion of ingredients in coatings and adhesion of those to a substrate. To make water-based paints accept additives, such as UV absorbers, they need soaps to break their surface tension. These additives help the ingredients to spread evenly throughout the coating. Plus, they help the coating stick to the surface.

How to Reduce VOCs in Coatings and Adhesives

To reduce volatile organic compounds in paints, coatings and adhesives, you can use several strategies. Application methods can reduce VOCs released from paints. Plus, formulation methods that balance specific benefits of the product with VOC allowances can also mitigate VOC levels.  

At the Application Level

When applying paints, spray painting a surface can release extra VOCs from overspray. To reduce the VOCs released, choose more appropriate spray-painting methods that reduce the wasted paint.

Transfer efficiency is the key to cutting VOCs. The higher the transfer efficiency, the more paint reaches the target surface. High transfer efficiency reduces the VOCs that painters expose themselves to by cutting the amount of paint that does not cover the target surface. Plus, it will reduce wasted paint and extend the lives of the painting booth filters.

Using automation technology to apply spray paint improves transfer efficiency and requires less paint. The precision of robots ensures the optimum amount of paint used for coating while cutting waste.

At the Formulation Level

Even more important than cutting VOCs during application is formulating paints with lower VOC amounts. However, the VOC content often comes from solvents necessary for obtaining desired properties from the paint. You can use a few strategies to include these ingredients in the paint while reducing unwanted compounds.

First, consider switching to low VOC solvents. These solvents have lower amounts of VOCs. Some coating formulations use both water-based and solvent-based parts, which reduces the overall VOCs while getting some benefits of solvent-based components.

Another option is choosing specific criteria for the final product and choosing ingredients that meet those while limiting the amount of VOCs they contribute. For instance, when creating UV-resistant paint, look for UV-resistant additives that meet or exceed VOC requirements.

Finally, explore alternatives to high-VOC products by considering water-based solvents. These use water to carry the components instead of higher VOC-containing solvents. Additives to the water-based paint can improve its properties such as flow and thickness to create similar performance levels as solvent-based paint.

Contact Active Minerals International (AMI) About Our Mineral Solutions for Water-Based Adhesives,
Paints and Sealants

At AMI, we provide mineral solutions that can help reduce VOC content in paints, sealants and adhesives. For example, our solutions for water-based adhesives include MIN-U-GEL® 400 and ACTI-GEL® 208 gel-quality attapulgite products. Depending on how they are used, MIN-U-GEL 400 and ACTI-GEL 208 can improve the properties
of flow & leveling, stability and thickness for water-based solutions. Including MIN-U-GEL 400 and ACTI-GEL 208 products in your formula may allow you to extend the applications of water-based paints, replacing solvents and reducing VOCs.

Contact the team at AMI to find out
how to learn more about these mineral product options to improve the performance of your sealants,
paints, adhesives and coatings.