There are times in the regulatory rule development process where opportunities arise that allow for rules to be made that can have an impact for decades to come. The printing industry just experienced one of those moments with the recent changes to South Coast Air Quality Management District’s (SCAQMD) Rule 1171. The rule sets limits on volatile organic compounds (VOC) to control emissions for cleaning solvents.
SCAQMD is the agency that regulates air pollution emissions in the Los Angeles area. The rule change is one of the most significant revisions that solves a 20-year problem of offset, letterpress, and screen printers struggling to clean their presses. It will also have a long-term impact on all of these printing processes throughout the state and perhaps the remainder of the country.
PRINTING United Alliance successfully negotiated with the SCAQMD to revise their cleaning solvent rule to include an alternative VOC limit. This breakthrough will have significant benefits for the printing industry, and the alternative limit, based on a concept of Maximum Incremental Reactivity (MIR), will make these solutions more effective and economical.
Rule 1171 Background
Rule 1171 was adopted on August 2, 1991 and has since been amended ten times. The revision that just occurred was due to the SCAQMD banning two chemicals because of their toxicity that are considered exempt from the definition of a VOC. The chemicals, tert-Butyl Acetate (T-BAC) and para chlorobenzotrifluoride (PCBTF) were used in cleaning solvent blends to meet the Rule 1171 VOC content limit of 100 gram/liter.
Of the two, only PCBTF was found in cleaning solutions used by printing operations. About 40% of the cleaning solvents identified contained PCBTF. These exempt compounds were utilized by manufacturers of solvent cleaning materials to formulate cleaning solvents to comply with the 100 gram/liter limit.
Several of the previous amendments involved revising the limits for cleaning solvents used in printing operations. Low VOC solvent cleaning materials that could meet the 100 gram/liter limit were not available at the time the initial rule change occurred, and the technology assessment encountered unforeseen delays. By May 2006, a technology assessment indicated that low VOC alternative materials such as water-based cleaners, blends of VOC exempt solvents, and methyl esters could be used to clean press rollers and blankets.
Initially, the test results indicated success in the performance of low VOC cleaning materials for removing conventional inks from printing presses hand wipe (manual) and automatic cleaning of rollers and blankets. Unfortunately, the long-term experience of using these cleaning solutions demonstrated that they were not effective at cleaning and had significant detrimental performance and economic problems. These problems included spontaneous combustion, swelling rollers and blankets, residue that needed a second cleaning step, incompatibility with some automatic blanket wash systems, plate blinding, stripping images from screens, and much higher costs. In essence, they were not workable for printing operations, leaving no viable solution until now.
Maximum Incremental Reactivity
All organic chemicals or VOCs released into the atmosphere will react with other chemicals and pollutants in the presence of sunlight to form ozone and smog. This concept is called photochemical reactivity and can be measured. Maximum Incremental Reactivity (MIR) is one measure of photochemical reactivity. It estimates the weight of ozone produced from the weight of a chemical (e.g. grams of ozone per gram of chemical) under worst case conditions. Using the MIR approach has emerged as a control strategy because using solvents with lower MIR values will help reduce ozone and smog formation.
Alternative MIR Limit for Printing Industry Cleaning Solutions
The Alliance initiated discussions with the SCAQMD over the need to provide an alternative limit for cleaning solutions as the current one has not been viable. This led to a conversation on using the MIR approach as an alternative limit, which shifted to focus on what would be an appropriate MIR limit for the screen, lithographic, and letterpress presses. This required extensive research and conversations with cleaning solvent suppliers and professionals serving on the Alliance’s Ink and Chemical Advisory Board.
The Alliance and SCAQM had intense negotiations that resulted in the establishment of a new alternative MIR limit of 0.70 g O3/g VOC. This limit was nearly double the 0.38 grams of ozone per VOC that SCAQM had initially proposed. The new VOC limit using the MIR concept is the solution that has been elusive for the past 34 years. It will allow for more flexible and cost-effective cleaning solutions based on traditional chemistry. The good news is that some suppliers already have solutions that meet this new limit.
Summary and Conclusion
The introduction of using a MIR value as an alternative in the printing industry to control emissions from cleaning solutions is historic as it is the first time in decades that there has been a new approach introduced to reduce the formation of ozone and smog. Most importantly, it now allows the printing industry to use cleaning solutions that are effective, less costly, and will not negatively impact the printing process.
The use of MIR is innovative in controlling ozone formation because it acknowledges that not all VOCs have the same reactivity. This allows for more targeted and efficient regulatory measures, focusing on the VOCs that have the highest potential to form ozone, thereby optimizing efforts to reduce ozone pollution and improve air quality.
Now that the alternative limit has been adopted by the SCAQMD, the Alliance anticipates that the other Air Quality Management Districts in the state will adopt the limit. In many instances, the SCAQMD will set a new standard for air pollution control, and the others will adopt this standard.
In this article, Gary Jones, Vice President of EHS Affairs, PRINTING United Alliance addresses environmental regulatory issues in California. More information about these issues can be found at Business Excellence-Environmental, Health, and Safety Affairs or if you have additional questions specific to how these issues may affect your business, reach out to Gary directly at gjones@printing.org.
To become a member of the Alliance and learn more about how our subject matter experts can assist your company with services and resources such as those mentioned in this article, please contact the Alliance membership team: 888-385-3588 / membership@printing.org.