VOC Content

Detailed Description

Volatile Organic Compound (VOC) content refers to the amount of volatile organic compounds present in a product or material. VOCs are organic chemicals that have a high vapor pressure at ordinary room temperature, causing them to evaporate or sublimate from liquid or solid form into the surrounding air. In the context of a Safety Data Sheet (SDS), VOC content provides important information for environmental compliance, workplace safety, and product performance.

The definition of VOCs can vary by regulatory jurisdiction:

US EPA: Organic compounds that participate in atmospheric photochemical reactions, excluding those specifically listed as exempt.
EU: Any organic compound having an initial boiling point less than or equal to 250°C measured at a standard pressure of 101.3 kPa.
California Air Resources Board (CARB): Any volatile compound containing at least one atom of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate.

VOC content can be expressed in several ways:

Mass per volume: Grams per liter (g/L) or pounds per gallon (lb/gal), often specified "less water and exempt compounds"
Mass percentage: Percent by weight (% w/w)
Volume percentage: Percent by volume (% v/v)
Emission rate: Mass emitted per time (e.g., g/hour)

Importance in Safety Data Sheets

VOC content information in an SDS is important for several reasons:

Regulatory compliance: Many jurisdictions regulate VOC content in products such as paints, coatings, adhesives, and consumer products.
Environmental impact: VOCs can contribute to air pollution, smog formation, and ozone depletion.
Workplace safety: VOC emissions can affect indoor air quality and worker exposure.
Health hazards: Many VOCs have associated health effects, ranging from eye and respiratory irritation to more serious conditions.
Fire and explosion hazards: Many VOCs are flammable and can create fire or explosion hazards.
Product performance: VOC content can affect drying time, adhesion, durability, and other performance characteristics.
Green building certification: VOC content is often a criterion for green building standards such as LEED.
Consumer information: Increasingly important for consumer product selection, especially for those with sensitivities or environmental concerns.

Measurement Methods

Several techniques are used to determine VOC content:

Method	Description	Typical Applications
EPA Method 24	Determines VOC content by measuring weight loss after heating	Paints, coatings, inks
ASTM D2369	Measures volatile content by weight loss after heating	Paints, coatings, adhesives
ASTM D3960	Calculates VOC content based on composition and density	Paints, coatings
Gas Chromatography (GC)	Separates and quantifies individual VOCs	Detailed VOC speciation, low concentrations
Headspace Analysis	Analyzes VOCs in the vapor phase above a sample	Liquids, solids with low VOC content
Thermal Desorption	Collects VOCs on adsorbent material, then thermally releases for analysis	Air and gas samples, emissions testing
Flame Ionization Detection (FID)	Detects organic compounds based on ionization in a hydrogen flame	Total VOC measurements, continuous monitoring
Calculation Method	Based on formulation data and known VOC content of ingredients	Product development, preliminary assessments

VOC Regulatory Limits and Categories

US EPA Architectural Coatings Rule Limits (Selected Categories)

Product Category	VOC Limit (g/L)*	Classification
Flat Coatings	50	Very Low
Non-flat Coatings	100	Low
Non-flat High Gloss	150	Low
Primers and Sealers	100	Low
Floor Coatings	100	Low
Industrial Maintenance Coatings	250	Moderate
Rust Preventative Coatings	250	Moderate
Stains	250	Moderate
Varnishes	350	High

*Less water and exempt compounds

EU Directive 2004/42/CE Limits (Selected Categories)

Product Category	VOC Limit (g/L)*	Classification
Interior Matt Walls and Ceilings	30	Very Low
Interior Glossy Walls and Ceilings	100	Low
Exterior Walls of Mineral Substrate	40	Very Low
Interior/Exterior Trim and Cladding Paints	130	Low
Interior/Exterior Trim Varnishes and Woodstains	130	Low
Two-pack Reactive Performance Coatings	140	Low

*Ready to use product

General VOC Content Classification

Classification	VOC Content Range	Examples
Zero VOC	<5 g/L	Some water-based paints, certain powder coatings
Very Low VOC	5-50 g/L	Low-VOC water-based paints, certain adhesives
Low VOC	50-150 g/L	Many water-based coatings, some adhesives
Moderate VOC	150-250 g/L	Some water-based coatings, certain solvent-based products
High VOC	250-500 g/L	Many solvent-based coatings, some industrial products
Very High VOC	>500 g/L	Traditional solvent-based products, some specialty coatings

Common VOCs and Their Properties

Compound	Common Sources	Boiling Point (°C)	Health and Environmental Concerns
Acetone	Solvents, nail polish remover	56	Eye and respiratory irritation; exempt from VOC regulations in US
Benzene	Gasoline, industrial processes	80	Carcinogen, blood disorders
Ethanol	Alcoholic beverages, solvents	78	Relatively low toxicity; flammable
Formaldehyde	Resins, preservatives	-19	Carcinogen, respiratory irritant
Methylene Chloride	Paint strippers, degreasers	40	Potential carcinogen, central nervous system effects
Toluene	Paints, adhesives, printing inks	111	Neurological effects, reproductive harm
Xylene	Paints, varnishes, adhesives	138-144	Neurological effects, respiratory irritation
Ethylene Glycol	Antifreeze, some paints	197	Toxic if ingested, low volatility limits air exposure
d-Limonene	Citrus-based cleaners, fragrances	176	Skin sensitizer, environmental concerns
2-Butoxyethanol	Cleaning products, paints	171	Blood effects, respiratory irritation

Exempt Compounds

Some jurisdictions exempt certain compounds from VOC regulations due to their low photochemical reactivity or minimal contribution to smog formation. These compounds are not counted in VOC content calculations for regulatory purposes, though they may still have other health or environmental concerns.

Examples of US EPA Exempt Compounds

Acetone
Methyl acetate
Parachlorobenzotrifluoride (PCBTF)
t-Butyl acetate (TBAC)
Dimethyl carbonate
Propylene carbonate
Many hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs)
Methylene chloride
Perchloroethylene
Siloxanes: cyclic, branched, or linear completely methylated

Note that exempt status varies by jurisdiction. For example, acetone is exempt under US EPA regulations but not under all California Air Districts or EU regulations.

VOCs and Health/Environmental Concerns

VOCs can have various health and environmental impacts:

Health effects: Many VOCs can cause eye, nose, and throat irritation, headaches, nausea, and damage to the liver, kidneys, and central nervous system. Some VOCs are known or suspected carcinogens.
Indoor air quality: VOCs can accumulate in indoor environments, potentially reaching concentrations much higher than outdoors, especially in new or recently renovated buildings.
Photochemical smog: VOCs react with nitrogen oxides in the presence of sunlight to form ground-level ozone and photochemical smog, which can cause respiratory problems and damage vegetation.
Ozone depletion: Some VOCs, particularly certain halogenated compounds, can contribute to stratospheric ozone depletion.
Global warming: Some VOCs have high global warming potential and can contribute to climate change.
Environmental persistence: Certain VOCs can persist in the environment and bioaccumulate in organisms.

The specific health and environmental impacts depend on the particular VOC, its concentration, and exposure duration. Regulatory limits aim to minimize these impacts while balancing practical considerations for product performance and manufacturing.

Examples of VOC Content Descriptions in SDSs

"VOC content: 250 g/L (less water and exempt compounds)"
"VOC: 15% by weight"
"VOC content: <5 g/L (EU Directive 2004/42/CE)"
"VOC: 2.1 lbs/gal (252 g/L)"
"VOC content: Complies with SCAQMD Rule 1168 (<50 g/L)"
"VOC emissions: Meets CDPH Standard Method v1.2 (California Section 01350)"
"VOC content: 0 g/L (product contains only exempt VOCs)"
"VOC content: 420 g/L (as supplied); 120 g/L (as applied, after dilution)"

Regulatory Framework

VOC regulations vary by jurisdiction and product category:

United States:
- EPA National Volatile Organic Compound Emission Standards for Consumer Products
- EPA National Volatile Organic Compound Emission Standards for Architectural Coatings
- California Air Resources Board (CARB) Consumer Products Regulations
- South Coast Air Quality Management District (SCAQMD) Rules
- Ozone Transport Commission (OTC) Model Rules
European Union:
- Directive 2004/42/CE (Paints Directive)
- Directive 2010/75/EU (Industrial Emissions Directive)
- Various national and local regulations
Other regions:
- Canada: Canadian Environmental Protection Act (CEPA) and provincial regulations
- Asia: Various national and local regulations, often modeled after US or EU approaches

Compliance with VOC regulations is mandatory in many jurisdictions, with penalties for non-compliance that can include fines, product recalls, and sales restrictions.

Best Practices

When reporting VOC content in an SDS:

Clearly specify the units (g/L, % w/w, etc.) and the basis of calculation (e.g., "less water and exempt compounds")
Reference the relevant regulatory standard or test method used for determination
For products with multiple components (e.g., two-part coatings), provide VOC content for individual components and the mixed product
For products with variable VOC content (e.g., tintable bases), provide the range or maximum value
Indicate whether the value represents as-supplied or as-applied conditions (after recommended thinning or dilution)
For products containing exempt VOCs, clearly indicate this and provide total VOC content including exempt compounds if relevant
For products marketed in multiple jurisdictions, consider providing VOC content according to different regional definitions
Include information on VOC emissions (e.g., CDPH Standard Method results) for indoor air quality considerations if available
Ensure consistency between VOC content information and other related properties in the SDS (e.g., solvent content, flash point)
Update VOC information when formulations change or regulatory definitions are revised