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7 DE Admin Code 1124 “Control of Volatile Organic Compound Emissions”

47.0 Offset Lithographic Printing and Letterpress Printing

(March 2011 Final Clean Revision) 

mm/dd/2011

47.1 Applicability

47.1.1 The provisions of 47.0 of this regulation apply to any offset lithographic or letterpress

printing press. Except as provided in 47.1.2 of this regulation, every owner or operator of 

any offset lithographic or letterpress printing press shall comply with the provisions of 

47.0 of this regulation on and after [insert effective date of this revision of 47.0 of this

regulation].

47.1.2 Transition period for existing permitted sources. Every owner or operator of any offset 

lithographic printing press that is subject to a permit issued pursuant to 7 DE Admin 

Code 1102 or 1130 containing all applicable conditions of 47.0 of this regulation, as that 

regulation existed on November 29, 1994, shall comply with those permit conditions for 

up to one year after the effective date of this revision of 47.0 of this regulation. Every 

owner or operator of any letterpress printing press that is subject to a permit issued 

pursuant to 7 DE Admin Code 1102 or 1130 shall comply with the permit’s conditions for 

letterpress printing for up to one year after the effective date of this regulation. On and 

after the date one year after the effective date of this revision of 47.0 of this regulation, 

every such owner or operator of any offset lithographic or letterpress printing press shall 

comply with the provisions of 47.0 of this regulation.

47.1.3 Except as specified in 47.6.1 of this regulation, the provisions of 47.0 of this regulation do 

not apply to any offset lithographic and letterpress printing press within a facility whose 

total actual volatile organic compound (VOC) emissions from all offset lithographic and 

letterpress printing operations (including emissions from cleaning solutions used on 

lithographic printing presses) are less than 6.8 kilograms (kg) (15 pounds [lb]) VOCs per 

day before application of capture systems and control devices.

47.1.4 Any facility that becomes or is currently subject to the provisions of 47.0 of this regulation 

by exceeding the applicability threshold in 47.1.23 of this regulation shall remain subject 

to 47.0 of this regulation even if its emissions later fall below the applicability threshold.

47.1.5 Any facility that is currently subject to a state or federal rule promulgated pursuant to the 

Clean Air Act Amendments of 1977 by exceeding an applicability threshold is and shall 

remain subject to these provisions, even if its throughput or emissions have fallen or later 

fall below the applicability threshold.

47.2 Definitions. As used in 47.0 of this regulation, all terms not defined herein shall have the 

meanings given them in the November 15, 1990 Clean Air Act Amendments (CAAA), or in 

2.0 of this regulation.

“Alcohol” means a chemical compound consisting of the hydroxyl (OH) group attached to an 

alkyl radical and having the general formula CnH2n+1OH, such as ethanol, n-propanol, and 

iso-propanol.
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“Alcohol substitute” means a non-alcohol additive that contains VOCs and is used in the 

fountain solution to reduce the surface tension of water or to prevent piling (ink build-up).

“Batch” means a supply of fountain solution that is prepared continuously or as a batch and 

that is used without alteration until completely used or removed from the printing process.

“Cleaning solution” means a liquid that is used to remove ink, including dried ink, and 

debris from the operating surfaces of the printing press and its parts.

“Fountain solution” means a mixture of water and non-volatile printing chemicals, and 

additives which reduce the surface tension of the water. The fountain solution wets the nonimage areas so that the ink is maintained within the image areas.

“Heatset” means any operation in which heat is required to evaporate ink oil from the 

printing ink.

“Letterpress printing” means a printing process in which the image is raised relative to the 

non-image area and the paste ink is transferred to the substrate directly from the image 

surface.

“Lithography” or “lithographic printing” means a printing process in which the image and 

non-image areas are chemically differentiated; the image area is oil-receptive and the nonimage area is water-receptive. This method differs from other printing methods, in which the 

image is a raised or recessed surface.

“Non-heatset” or “coldset” means any operation in which printing inks are set without the 

use of heat. For the purposes of 47.0 of this regulation, ultraviolet-cured and electron beamcured inks are considered non-heatset operations.

“Offset lithographic printing” means a printing process that transfers the ink film from the 

lithographic plate to an intermediary surface (blanket), which, in turn, transfers the ink film to 

the substrate.

“Press” means a printing production assembly that is composed of one or many units to 

produce a printed sheet or web.

“Sheet-fed” means a printing operation in which individual sheets of substrate are fed to the 

press sequentially.

“Total actual VOC emissions” means the quantity of VOCs emitted from all lithographic 

and letterpress printing operations, including VOC emissions from cleaning materials and 

activities, during a particular time period.

“Unit” means the smallest complete printing component of a printing press.

“Web” means a continuous roll of paper used as the printing substrate.

47.3 Standards

47.3.1 No owner or operator of a heatset offset lithographic printing press or a heatset 

letterpress printing press shall operate the printing press unless the owner or operator
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installs a control device to reduce VOC emissions from the press dryer exhaust vent by

complying with 47.3.1.1, or 47.3.1.2, or 47.3.1.3 of this regulation at all times the press 

operates:

47.3.1.1 At least 90%, by weight, if the first installation date of the control device is prior to 

[insert the effective date of this regulation].

47.3.1.2 At least 95%, by weight, if the first installation date of the control device is on or

after [insert the effective date of this regulation].

47.3.1.3 Maintaining a maximum press dryer exhaust outlet VOC concentration of 20 

parts per million by volume (ppmv) as carbon (C1) on a dry basis.

47.3.2 No owner or operator of an offset lithographic printing press shall operate the printing 

press unless the owner or operator meets the requirements listed under 47.3.2.1, 

47.3.2.2, or 47.3.2.3 of this regulation.

47.3.2.1 For any heatset web offset lithographic printing press:

47.3.2.1.1 When, the fountain solution contains alcohol, the fountain solution 

on-press (as applied) VOC content shall be maintained:

47.3.2.1.1.1 At 1.6% or less (by volume), or 

47.3.2.1.1.2 At 3.0% or less (by volume) and the temperature of 

the fountain solution shall be maintained at or below 

15.5 degrees Celsius (°C) (60 degrees Fahrenheit 

[°F]).

47.3.2.1.2 When the fountain solution contains no alcohol, the fountain 

solution on-press (as-applied) VOC content shall be maintained at 

3.0% or less (by volume). 

47.3.2.2 For any non-heatset web offset lithographic printing press:

47.3.2.2.1 There shall be no alcohol in the fountain solution, and 

47.3.2.2.2 The fountain solution on-press (as-applied) VOC content shall be 

maintained at 3.0% or less (by volume). 

47.3.2.3 For any sheet-fed offset lithographic printing press, the fountain solution on-press 

(as-applied) VOC content shall be maintained:

47.3.2.3.1 At 5.0% or less (by volume), or

47.3.2.3.2 At 8.5% or less (by volume) and the temperature of the fountain 

solution shall be maintained at or below 15.5°C (60°F).

47.3.3 No owner or operator of an offset lithographic printing press or a letterpress printing press 

shall operate the printing press unless the owner or operator reduces VOC emissions 

from cleaning solutions by meeting requirements in 47.3.3.1or 47.3.3.2, and 47.3.3.3, of 

this regulation:
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47.3.3.1 Using a cleaning solution with a 30% or less (as used) VOC content. 

47.3.3.2 Using cleaning solutions with a VOC composite partial vapor pressure less than 

10 millimeters (mm) mercury (Hg) (0.4 inches [in] Hg) at 20°C (68°F). The VOC 

composite partial vapor pressure is calculated as follows:

(47-1)

Where:

Wi = Weight of the i

th VOC compound, in grams (g);

Ww = Weight of water, in g;

We = Weight of exempt compound, in g;

MWi = Molecular weight of the i

th VOC compound, in grams per gram-mole

;

MWw = Molecular weight of water, in ;

MWe = Molecular weight of exempt compound, in ;

PPC = VOC composite partial pressure at 20°C, in mmHg

VPi = Vapor pressure of the i

th VOC compound at 20°C, in mmHg

47.3.3.3 Keeping all cleaning solutions and used shop towels or cloths in closed 

containers.

47.4 Control devices. An owner or operator of an offset lithographic printing press or a letterpress 

printing press equipped with a control system shall ensure that:

47.4.1 The capture system and control device are operated at all times when the printing press 

is in operation, and compliance with 47.0 of this regulation is demonstrated through the 

applicable coating analysis and capture system and control device efficiency test 

methods specified in Appendix B, Appendix D, and Appendix E of this regulation and 

in accordance with the capture efficiency test methods specified in Appendix D of this 

regulation.

47.4.2 The control device is equipped with the applicable monitoring equipment specified in 2.0 

of Appendix D of this regulation, and the monitoring equipment is installed, calibrated, 

operated, and maintained according to the vendor's specifications at all times the control 

device is in use.

47.5 Test methods and procedures.

47.5.1 The VOC content of each ink, the alcohol content of each fountain solution, and the 

efficiency of each capture system and control device shall be determined by the 

applicable test methods and procedures specified in Appendix A through Appendix D of 

this regulation to establish the records required under 47.6 of this regulation.
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47.5.2 To demonstrate compliance with the emission control requirements of 47.0 of this

regulation, the facility affected by 47.0 of this regulation shall be run at maximum 

operating conditions and flow rates during any emission testing.

47.5.3 Emission tests for facilities using an add-on dryer exhaust control device shall include an 

initial test, when the control device is installed and in operation, that demonstrates 

compliance with 47.3.1 of this regulation. 

47.5.4 To determine compliance with 47.3.2 of this regulation, the owner or operator of an offset 

lithographic printing facility shall perform the following procedures:

47.5.4.1 A sample shall be taken of the fountain solution (as used) from the fountain tray 

or reservoir that contains a fresh batch of fountain solution (after mixing), for 

each unit or centralized reservoir, to determine the alcohol content of the fountain 

solution in accordance with 47.3.2.1 through 47.3.2.3 of this regulation, before 

the fountain solution is used.

47.5.4.2 A direct measurement of the alcohol content of the fountain solution sample or 

samples shall be performed in accordance with the method specified in 

Appendix L of this regulation.

47.5.4.3 Alternatively, a sample of the fountain solution (as used) may be taken from the 

fountain tray or reservoir of fountain solution during use and measured with a 

hydrometer or refractometer that has been standardized with tests performed in 

accordance with 47.5.4.1 and 47.5.4.2 of this regulation. The unit shall be 

considered in compliance with 47.3.2.1 through 47.3.2.3 of this regulation if the 

refractometer or hydrometer measurement is less than or equal to the 

measurement obtained by the method specified in Appendix L of this regulation 

plus 10%.

47.5.4.4 The VOC content of a fountain solution containing alcohol substitutes or nonalcohol additives shall be established with proper recordkeeping and the 

manufacturer's technical information of the VOC content of the concentrated 

alcohol substitute and included in facility records. Records shall include the 

amount of concentrated substitute added per quantity of fountain water; the date 

and time of preparation if the fountain solution is mixed as a batch; and the 

calculated VOC content of the final solution to fulfill the requirements listed in 

47.3.2 of this regulation.

47.5.5 To determine compliance with 47.3.2.1.1.2 and 47.3.2.3.2 of this regulation, an owner or 

operator of an offset lithographic printing facility shall use a thermometer or other 

temperature detection device capable of reading to 0.28°C (0.5°F) accuracy to ensure 

that a refrigerated fountain solution containing alcohol is below 15.5°C (60°F) at all times.

46.5.6 To determine compliance with 47.3.3 of this regulation, an owner or operator of an offset 

lithographic printing press or a letterpress printing press shall:

47.5.6.1 Take a sample of the cleaning solution (as used) to demonstrate compliance with 

the cleaning solution VOC content limitations listed in 47.3.3 of this regulation. If 

the cleaning solution is used as received from the supplier without dilution or 

alteration, the manufacturer's technical information may be used to demonstrate 

compliance.
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47.5.6.2 Use the method specified in Appendix L of this regulation to determine the VOC 

content of the cleaning solution (as used). Alternatively, the VOC content and 

VOC partial pressure of the cleaning solution may be established using the 

manufacturer's technical data. If the cleaning solution is prepared through the 

dilution of concentrated materials, the blending ratio and VOC content of the 

concentrate may be used to determine the "as used" VOC content of the 

cleaning solution.

47.6 Recordkeeping and reporting.

47.6.1 Requirements for sources below threshold emission limit. Any owner or operator of any 

offset lithography printing facility, any letterpress printing facility, or any facility with both 

offset lithographic and letterpress printing operations, that emits less than the threshold 

limit according to 47.1 of this regulation shall comply with the following requirements:

47.6.1.1 Initial certification. Within six months after [insert the effective date of this 

revision of 47.0 of this regulation], or upon initial startup of a new printing press, 

the owner or operator shall certify to the Department that the facility emits less 

than the threshold limit according to 47.1 of this regulation. Such certification 

shall include the following information:

47.6.1.1.1 The name and location of the facility.

47.6.1.1.2 The address and telephone number of the person responsible for the facility.

47.6.1.1.3 A declaration that the facility is not subject to the requirements of 47.0 of this 

regulation because of the criteria listed in 47.1 of this regulation.

47.6.1.1.4 The calculations demonstrating that total actual VOC emissions from all 

offset lithographic and letterpress printing presses at the facility are and will 

be less than 6.8 kg (15 lb) per day before the application of capture systems 

and control devices.

47.6.1.1.5 A description of the instrument or method by which the owner or operator 

accurately measured or calculated the volume of ink applied and the amount 

that can potentially be applied each year on each printing press.

47.6.1.2 Recordkeeping. On and after [insert the effective date of this revision of 47.0 of 

this regulation], the owner or operator shall collect and record all of the following 

information each year for each offset lithographic printing press and each 

letterpress printing press and maintain the information at the facility for a period 

of five years:

47.6.1.2.1 The name and identification number of each ink, as applied, each year on 

each printing press.

47.6.1.2.2 The total actual VOC emissions as calculated in 47.6.1.1.4 of this regulation 

using the VOC content for that year.

47.6.1.3 Reporting. On and after [insert the effective date of this revision of 47.0 of this 

regulation], any record showing that total actual emissions of VOCs from all 
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offset lithographic printing presses and all letterpress printing presses exceed 6.8 

kg (15 lb) per day before the application of capture systems and control devices

shall be reported by sending a copy of the record to the Department within 45 

calendar days after the exceedance occurs. This requirement is in addition to any 

other State of Delaware exceedance reporting requirements.

47.6.2 Requirements for sources above threshold emission limit. Any owner or operator of any 

offset lithography printing facility, or any letterpress printing facility, or any facility with 

both offset lithographic and letterpress printing operations, that emits greater than the 

threshold limit according to 47.1 of this regulation shall comply with the following 

requirements:

47.6.2.1 Initial certification. Within six months after [insert the effective date of this 

revision of 47.0 of this regulation], or upon initial startup of a new printing press, 

the owner or operator shall certify to the Department that the facility emits greater 

than the threshold limit according to 47.1 of this regulation. Such certification 

shall include the following information:

47.6.2.1.1 The name and location of the facility.

47.6.2.1.2 The address and telephone number of the person responsible for the facility.

47.6.2.1.3 The calculations demonstrating that total actual VOC emissions from all 

aspects of printing operations at the facility are and shall be greater than 15 

lb (6.8 kg) per day before the application of capture systems and control 

devices.

47.6.2.1.4 A description of the instrument or method by which the owner or operator 

accurately measured or calculated the volume of ink applied and the amount 

that can potentially be applied each year on each printing press.

47.6.2.2 Recordkeeping. On and after [insert the effective date of this revision of 47.0 of 

this regulation], the owner or operator shall collect and record all of the following 

information each year for each offset lithographic printing press and each 

letterpress printing press and maintain the information at the facility for a period

of five years:

47.6.2.2.1 The name and identification number of each ink, as applied, each year on 

each printing press.

47.6.2.2.2 The weight of VOCs per volume of coating solids and the volume of solids of 

each ink, as applied, each year on each printing press.

47.6.2.2.3 The total actual VOC emissions as calculated in 47.6.2.1.3 of this regulation 

using the VOC content for that year.

47.6.3 Requirements for sources using an add-on dryer exhaust control device.

47.6.3.1 Within six months after [insert the effective date of this revision of 47.0 of this 

regulation], or upon initial startup of a new printing press, the owner or operator 

of a heatset offset lithographic printing press, or a heatset letterpress printing 

press, shall install, calibrate, maintain, and operate a temperature monitoring 
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device, according to the manufacturer's instructions, at the outlet of the control 

device or at a location approved by the Department and the EPA. The monitoring 

temperature shall be set during the testing required to certify compliance with the 

requirements of 47.4 of this regulation. Monitoring shall be performed only when 

the unit is operational.

47.6.3.2 The temperature monitoring device shall be equipped with a continuous recorder 

and shall have an accuracy of 0.28°C (0.5°F).

47.6.3.3 The dryer pressure shall be maintained lower than the press room area pressure 

such that air flows into the dryer at all times when the press is operating. A 100% 

emissions capture efficiency for the dryer shall be demonstrated using an air flow 

direction measuring device.

47.6.4 Requirements for monitoring fountain solution VOC concentration. On and after [insert 

the effective date of this revision of 47.0 of this regulation], the alcohol concentration in 

the fountain solution shall be monitored to provide data that can be correlated to the 

amount of material used when the fountain solution complies with the limits listed in 

47.3.2.1 through 47.3.2.3 of this regulation. One of the following methods shall be used to 

frequently measure the concentration of alcohol in the fountain solution:

47.6.4.1 The owner or operator of any offset lithographic printing press shall monitor the 

alcohol concentration of the fountain solution with a refractometer that is 

corrected for temperature at least once per 8-hour shift or once per batch, 

whichever is longer. The refractometer shall have a visual, analog, or digital 

readout with an accuracy of 0.5%. A standard solution shall be used to calibrate 

the refractometer for the type of alcohol used in the fountain. Alternatively, the 

refractometer shall be standardized with measurements performed to determine 

compliance, according to the procedures described in 47.5.4.1 and 47.5.4.2 of 

this regulation.

47.6.4.2 Alternatively, the owner or operator of any offset lithographic printing press shall 

monitor the alcohol concentration of the fountain solution with a hydrometer 

equipped with a temperature correction at least once per eight-hour shift or once 

per batch, whichever is longer. The hydrometer shall have a visual, analog, or 

digital readout with an accuracy of 0.5%. A standard solution shall be used to 

calibrate the hydrometer for the type of alcohol used in the fountain. Alternatively, 

the hydrometer shall be standardized with measurements performed to 

determine compliance, according to the procedures described in 47.5.4.1 and 

47.5.4.2 of this regulation.

47.6.4.3 The VOC content of the fountain solution may be monitored with a conductivity 

meter if it is determined that a refractometer or hydrometer cannot be used for 

the type of VOCs in the fountain solution. The conductivity meter reading for the 

fountain solution shall be referenced to the conductivity of the incoming water.

47.6.4.4 If, through recordkeeping for a period of 6 months or more, the printing process is 

shown to consistently meet the requirements in 47.3.2 and 47.5.4 of this 

regulation, the monitoring requirement may be waived or extended to a longer 

period of time upon prior approval by the Department.

47.6.5 Requirements for monitoring fountain solution temperature. On and after [insert the 

effective date of this revision of 47.0 of this regulation]:
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47.6.5.1 The owner or operator of any offset lithographic printing press using refrigeration 

equipment on the fountain solution shall install, maintain, and continuously 

operate a temperature monitor of the fountain solution reservoir.

47.6.5.2 The temperature monitor shall be attached to a continuous recording device such 

as a strip chart, recorder, or computer.

47.6.6 Requirements for Monitoring Cleaning Solution. On and after [insert the effective date of 

this revision of 47.0 of this regulation], for any offset lithographic printing press or any 

letterpress printing press with continuous cleaning equipment, flow meters shall be used 

to monitor the water and cleaning solution flow rates. The flow meters shall be calibrated 

so that the VOC content of the mixed solution is accurately measured to fulfill the 

requirements of 47.3.3 of this regulation.

47.6.7 Requirements for Monitoring Other Key Parameters. On and after [insert the effective 

date of this revision of 47.0 of this regulation], the owner or operator of any offset 

lithographic printing press or any letterpress printing press shall record daily, and make 

available to the Department within 45 calendar days upon the Department’s verbal or 

written request, the following key parameters:

47.6.7.1 The type of control device operating on any heatset offset lithographic printing 

press or any heatset letterpress printing press and the operating parameters 

specified in 47.3.1 of this regulation.

47.6.7.2 The operating standard selected to comply with the requirements listed in 

47.3.2.1 through 47.3.2.3 and 47.3.3 of this regulation.

47.6.7.3 The VOC content of the fountain solutions and cleaning solutions, to comply with 

the requirements listed in 47.5.4, 47.6.4, and 47.6.6 of this regulation.

47.6.7.4 The temperature of the fountain solution, to comply with the requirements listed 

in 47.6.5 of this regulation, if applicable.

47.6.7.5 For manual cleaning methods, the amount of cleaning solution and the amount of 

water added per batch of cleaning solution mixed.

47.6.7.6 For automatic cleaning methods, the flow rates of water and cleaning solution 

concentrate, as specified in 47.6.6 of this regulation.

47.6.7.7 Corrective actions taken when exceedances of any parameters, monitored 

according to the requirements of 47.4 or 47.5 of this regulation, occur.