Table of Contents
Solvent-Based Coatings: Regulatory Requirements
The Clean Air Act regulates the emission
of volatile organic
compounds (VOCs) (40 CFR Part 60) and
hazardous air pollutants
(HAPs), (40 CFR Part 61 and 40
CFR Part 63) and provides specific standards of performance to control
emissions from various types of coating operations (40
CFR Part 60). Solvent-based coatings typically contain more than
60% organic solvents classified as VOCs. Evaporation of the solvents
during application and curing may produce sufficient VOC and HAP emissions
to subject an operator to major source
requirements and Title V permitting
Controlling VOC emissions can be accomplished in two ways. First,
coatings with lower organic solvent content may be used. Otherwise,
air pollution control
equipment is required on application or curing equipment exhaust systems
to recover or incinerate the VOCs and HAPs before they are released from
As part of the Clean Water Act, Effluent
Guidelines and Standards for Metal Finishing (40 CFR Part 433) have
been established that limit concentrations of heavy
metals and toxic organics
in wastewater streams. Solvent-based coatings often contain materials
classified as toxic organics. These materials can enter the wastewater
through the use of water wash spray booths, when cleaning solvent-based
coatings from containers or equipment, or following accidental spills. Actual limits for effluent constituents depend on the size of the operation
and the amount of wastewater generated from the facility. If the facility
discharges directly to receiving
waters, these limits will be established through the facility's National
Pollutant Discharge Elimination System (NPDES) permit (40
CFR Part 122). Facilities which are indirect dischargers releasing
to a POTW
must meet limits in the POTW's discharge agreement. Wastewater streams
with concentrations exceeding permit limits will require pretreatment
prior to discharge to receiving waters or to a publicly
owned treatment works. Pretreatment may include separation of
liquid wastes to remove solvents, and settling or precipitation of solid
Solid and Hazardous Waste
Under the Resource Conservation and Recovery
Act (RCRA), organic finishing facilities are required to manage listed
and characteristic hazardous wastes (40 CFR
Part 261). Solvent-based coatings may contain constituents listed
or characterized as hazardous wastes. Residual solvent-based coating
materials, their containers, and contaminated materials (including rags,
masking material, coveralls, filters, and other process materials ) may
require treatment as hazardous waste depending on their formulation. Hazardous waste management (40 CFR Part 262)
includes obtaining permits for the facility in order to generate wastes,
meeting accumulation limits for waste storage areas, and manifesting waste
containers for off-site disposal. Responsibilities will vary according
to the amount of hazardous waste material generated; facilities generating
at least 100 kilograms of hazardous waste per month must comply with the
hazardous waste generator requirements of 40 CFR
Each state and/or region is primarily responsible for the regulation
of non-hazardous solid wastes (those not governed by the hazardous waste
provisions of RCRA). Check with state environmental agencies for
specific information or guidance.
The Emergency Planning and Community Right-to-Know
Act (EPCRA) requires facilities to notify employees, customers and
the surrounding community of certain hazardous chemicals and materials
(40 CFR Parts 355 and 370)
that are present on-site. Solvent-based coatings in sufficient quantities
may subject a facility to several EPCRA requirements. Facilities
may be required to inform the local
emergency planning committee (LEPC) and the state
emergency response commission (SERC) of the materials stored on site,
to devise emergency response plans for reacting to spills, and to notify
authorities of accidental spills and releases (40
CFR Parts 302 and 355). Solvent-based
coatings stored on-site may also require facilities to submit Material
Safety Data Sheets (MSDS) for these materials to state, regional, and
local organizations, while disposed volumes of the material may have to
be documented on annual Toxic
Release Inventory reports (40 CFR Part 372).
Do exhaust air streams have air pollution control equipment attached? Is that air pollution control equipment working properly? Does final
exhaust air have concentrations of pollutants below required levels?
Do solvent-based coatings come in contact with water streams? If
so, do concentrations of pollutants exceed limits established by the facility
NPDES permit or POTW discharge agreement?
? Are all solvent-based coatings and waterborne coatings wastes labeled
and packaged in accordance with 40 CFR Part 262,
Are wastes contaminated with solvent-based coatings classified as hazardous? If so, are the wastes handled and manifested in accordance with 40
CFR part 262, Subpart C properly and are the materials segregated from
Has the facility participated in local, regional, or state emergency response
planning activities? Have facility response plans been developed and coordinated
with local authorities?
Solvent-Based Coatings: Common Causes of Violations
Solvent-based coatings contain organic solvents classified as volatile
organic compounds and/or hazardous air pollutants that can evaporate and
accumulate above limits allowed by Clean Air Act Title V permits. Most solvent-based coatings have a VOC content of greater than 3.0 pounds
per gallon; and when large volumes of the material are used, ambient levels
of the volatile organic compounds and hazardous air pollutants can be great.
Solvent-based coatings are liquid materials that can easily contaminate
water streams. This contamination may be accidental, as with spilt
material entering a storm sewer, or intentional, as with the use of water
wash spray booths. Contaminated water streams may contain pollutants
in concentrations that exceed the limits established by facility NPDES
permits or POTW discharge agreements. In such cases, effluent, may
not be directly released to water systems or to publicly owned treatment
works without pretreatment.
Solvent-based coatings remaining on rags, filters, masking papers, and
coating containers may be considered hazardous waste. If hazardous,
the waste must be properly stored, manifested and disposed according to
RCRA standards (40 CFR Part 262).
Solvent-based coatings may contain substances defined as hazardous chemicals
or extremely hazardous substances. Depending on the quantity of material
on-site, facilities must have an MSDS for each formulation, maintain records
for TRI reporting, and cooperate with local emergency planning committees.
Solvent-Based Coatings: Sources of Pollution
Solvent-based coatings contain materials classified as volatile organic
compounds and hazardous air pollutants.
Solvent-based coatings may spill due to improper handling or leaks in containers. The liquid material may enter storm sewers if not properly contained, and
may contaminate water used in spill cleanup.
Solvent-based coatings may require organic solvents for cleanup of mixing
equipment, application equipment, coating containers, or spills. The organic solvents may be classified as volatile organic compounds or
hazardous air pollutants.
Solvent-based coatings may expire and no longer meet quality standards,
thus becoming waste. In addition, coatings that are not used completely
in a job and have no use in another job are considered waste as well.
Solvent-based coatings come in containers that become solid waste once
empty or when the coating is no longer useable or needed. Containers
can range from small quart or gallon cans to large barrels. Residual
coating material left inside the container adds to the volume of solid
Solvent-based coatings with a high-solids content may require heat to reach
the desired viscosity, thus requiring additional energy consumption.
Solvent-based Coatings: Pollution Prevention Opportunities
Substitute high-solids, waterborne, or powder coating materials for solvent-based
coatings. Compared to traditional solvent-based coatings, other high-solids,
waterborne and powder coatings contain much lower amounts of volatile organic
compounds. In addition, these materials have higher solids contents
which results in a lower volume of material needed for a given surface
Proper scheduling and procurement can reduce the amount of residual coating
material waste. To reduce residual coatings, buy only as much material
as needed to complete job. Mix remaining light colored coatings into
darker colored coatings where possible. Purchase coating materials
in the largest containers possible for the volume; since the surface area
to volume ratio of the container is lower, less material is left on the
inside of the containers to be thrown away. Work with coating vendors
to have larger containers returned for refilling. Rotate stock of
coatings to use older material first (first in - first out practice). Before discarding expired coatings, test to see if they would still meet
quality requirements. Donate or sell old and unwanted coating materials
as raw material to others or see if vendor will take it back.
Restrict traffic in storage areas to reduce spills and accidents. Keep storage and work areas clean so that spills and leaks are more noticeable
and reaction time to clean up is reduced. Control the temperature
in storage areas to prevent the freezing and heating of coating materials
that will spoil them.
Enclose or cover containers of coating material when not in use to minimize
the release of solvent vapors and lower the possibility of contamination
from facility dust and dirt.
Segregate non-hazardous coating solids from hazardous solvents and thinners,
and label containers to prevent mixing. Separation of the materials
reduces the amount of hazardous waste that is produced. Coating material
solids can be dried and treated as a solid waste, thus allowing for disposal
in a landfill.
Train employees on safe handling of materials and wastes and encourage
continuous improvement. Training familiarizes workers with their
responsibilities, which reduces spills and accidents.