Monitoring by Control Technique - Compliant (Low/No VOC/HAP) Inks and Coatings

Description

Many industry sectors involving surface coating operations are currently using coatings and (printing) inks containing low or no Volatile Organic compounds (VOCs) or Hazardous Air Pollutants (HAPs) in the formulation. These materials are often referred to as low- or no- VOC/HAP coatings. Although the term low- or no-VOC/HAP is not definitive in terms of the actual levels of VOC or HAP in a particular coating, most EPA and industry representatives use the term to mean "compliant coatings" or those materials having VOC/HAP contents equal to or less than any applicable limits. Examples of low- and no-VOC/HAP coatings include waterborne, UV-cured, high-solids, and powder coatings.

Replacing higher emitting (noncompliant) coatings with lower emitting (compliant) coatings is a good example of how coating manufacturers and end-users are promoting EPA Pollution Prevention (P2) strategy (in accordance with the national policy expressed in the Pollution Prevention Act of 1990). Pollution prevention is EPA first priority within an environmental management hierarchy that includes: 1) prevention; 2) recycling; 3) treatment; and 4) disposal or release.

Some examples of studies to evaluate the use of lower emitting coatings or solvents are listed below.

Case Studies: Low-VOC/HAP Wood Furniture Coatings, EPA-600/R-00-043 (PDF) (150 pp, 7.5 MB, About PDF) May 2000
Design for the Environment (DfE): Options for Cleaner Flexographic (Printing) Inks
Printing and Related Support Activites Sector (NAICS 323)
Design for the Environment (DfE): Lithography Publications List, EPA 744-F-96-022 (PDF) (8 pp, 426 K, About PDF) March 1997
RCRA in Focus: Printing, EPA 530-K-97-007(15 pp, 240 K, About PDF)

Monitoring Information

Monitoring low- and no-VOC/HAP coatings used in a coating operation is basically a two-step process. First, the owner or operator of the source using such materials demonstrates (and documents) the VOC/HAP content of each low- or no-VOC/HAP coating meets the applicable requirement(s). This can be done by product testing or using product data sheets, material safety data sheets, or other documentation from the coating manufacturer. Secondly, usage of each low- or no-VOC/HAP coating, along with product recovery records, can be monitored using purchase and shipping records or daily/weekly/monthly/yearly usage logs. Monitoring approaches range from maintaining written logs to the use of sophisticated computerized systems for tracking content and usage.

EPA continues to strive for streamlined monitoring requirements for those facilities whose compliance strategies are based on use of compliant materials, including low- and no- VOC/HAP coatings. Streamlining difficulties can result when requirements apply to different pollutants (VOC vs. HAP), use different units of applicability in compliance terms (volume of coating vs. volume of coating solids), and averaging times (daily vs. rolling 12-month averages).

Example Permits

If you elect to monitor compliance by measuring the VOC/HAP content of coatings, the permit application should include the following information:

the numerical compliance limit;
the sampling/measurement method to be used;
the frequency of sampling;
emissions calculation procedures;
the averaging period;
QA/QC procedures; and
recordkeeping procedures.

For most of the recently promulgated surface coating MACT rules, the compliance demonstration must include the calculations and supporting documentation showing that, during the compliance period, the owner or operator of the affected source used no coating with a VOC/HAP content that exceeded any applicable emissions limit. As part of the calculations and supporting documentation, the permittee may be asked to:

determine the mass fraction of VOC/HAP for each material used;
determine the volume fraction of coating solids for each coating;
determine the density of each coating; and
calculate the VOC/HAP content of each coating.

Links to some examples of monitoring requirements when using compliant coatings are presented below.

Example: Surface Coating of Metal Parts and Products

Surface Coating of Metal Parts and Products

1. No coating with a VOC content in excess of 275 g/l for baked coating, and 340 g/l for air-dried coating, shall be used. VOC content will be determined as grams of VOC per liter of coating applied (less water and exempt compounds).

2. No specialty coating with a VOC content in excess of the limits, expressed as grams of VOC per liter of coating applied (less water and exempt compounds), shall be used.

3. Each container or accompanying data sheet of any coating shall display the maximum VOC content of the coating, as applied, and after any thinning, and manufacturer’s thinning recommendation.

4. Operator shall maintain a daily record of the volume of coatings and solvents applied, volume coating/solvent mix ratio, VOC content of coating, VOC content of solvents used for surface preparation and clean up, the total quantity of VOC emitted in pounds and number of hours process equipment is operated. Record entries shall be initialed by person making entry.

5. VOC content of any coating shall be determined through the use of either product formulation data or analyzed by EPA Method 24.

Example: Surface Coating of Metal Cans

Surface Coating of Metal Cans

1. Metal can surface coating operations shall not use or apply any coating with a VOC content in excess of 660 grams of VOC per liter of coating, as applied, excluding water and exempt compounds.

2. Operator shall maintain and have available during an inspection, a current list of coatings in use providing all of coating data necessary to evaluate compliance including the following information as applicable: a) specific coatings, catalysts, and reducers used, b) mix ratio of components used, c) VOC content of each coating, as applied, and d) VOC content of each solvent used for cleanup and surface preparation.

3. Records shall be maintained on a daily basis.

4. VOC content of coating(s), as applied, and of solvents used for cleanup and surface preparation shall be determined by EPA Method 24 and analysis of halogenated exempt compounds shall be determined on an annual basis. If the coating/solvent manufacturers provide certification that the previously mentioned methods are used to determine the VOC content, copies of the coating/solvent product data sheets and the certifications may be maintained, used to calculate the VOC content of the coating, as applied, and shall be considered compliant with this condition.

5. The permittee shall comply with all Labeling and Test Methods requirements.

Example: Wood Furniture Manufacturing Operation

Wood Furniture Manufacturing Operation

1. The Permittee shall not discharge or cause the discharge into the atmosphere emissions from any wood product surface coating in excess of 1.0 pound Volatile Hazardous Air Pollutants (VHAP) per pound of solids, as applied, for finishing materials (including stains, washcoats, sealers, topcoats, basecoats, and enamels).

2. The Permittee shall comply with the above emission limitation by one of the following:

a. The application of low solvent technology such that the VHAP content of each and every finishing material (including stains, washcoats, sealers, topcoats, basecoats, and enamels) utilized does not exceed 1.0 pound VHAP per pound of solids, as applied; or

b. The application of low solvent technology where the monthly weighted average VHAP content of all finishing materials (including stains, washcoats, sealers, topcoats, basecoats, and enamels) utilized does not exceed 1.0 pound VHAP per pound of solids, as applied; or

c. The use of any combination of compliant finishing materials, as described in paragraph ‘a’, and an averaging approach, as described in paragraph ‘b’.