Date: September 24, 2015

To: Sharon Nizich, EPA/OAQPS/SPPD

From: Gabrielle Raymond, RTI International

Subject: Development of Cost and Emission Reduction Impacts for the Final Clay

Ceramics Manufacturing NESHAP

I. Introduction

In accordance with section 112 of the Clean Air Act (CAA), the U.S. Environmental 

Protection Agency (EPA) established national emission standards for hazardous air pollutants 

(NESHAP) on May 16, 2003, for the clay ceramics manufacturing industry, specifically the 

sanitaryware and ceramic tile industry sectors. Sanitaryware includes plumbing and bathroom 

fixtures such as toilets and sinks. Ceramic tile is used to cover floors and walls. The NESHAP 

regulated emissions of hydrogen fluoride (HF), hydrogen chloride (HCl), and particulate matter 

(PM)—a surrogate for hazardous air pollutant (HAP) metals—from new and reconstructed kilns 

located at clay ceramics facilities. On March 13, 2007, the D.C. Circuit Court vacated the 

emission standards for clay ceramics manufacturing due to issues associated with the 

methodology used to determine the minimum regulatory “floors” for new and existing units.

1

Therefore, on December 18, 2014, the EPA proposed new standards for clay ceramics 

manufacturing, including standards for HF, HCl, mercury (Hg), non-Hg HAP metals 

(specifically, the PM surrogate), and dioxins/furans (in terms of 2,3,7,8-tetrachlorodibenzo-pdioxin toxic equivalents (TEQ)). The EPA provided a 90-day public comment period following 

proposal of the Clay Ceramics Manufacturing NESHAP, during which all affected parties were 

given the opportunity to comment on the proposed rule. The EPA has considered the comments 

received and, as appropriate, incorporated them into the final rule.

The list of affected sources to be regulated has been expanded to include new and 

existing kilns, spray dryers (ceramic tile only), press dryers (floor tile only), and spray glaze 

operations. However, the facilities currently projected to be subject to the NESHAP include 

three sanitaryware facilities. The ceramic floor and wall tile facilities have taken the necessary 

steps to become synthetic area sources (i.e., have obtained a federally enforceable limit reducing 

 1 Sierra Club v. EPA, 479 F.3d 875 (D.C. Cir. 2007).
2

emissions below major source thresholds2

), and would not be subject to the major source Clay 

Ceramics Manufacturing NESHAP.

The purpose of this memorandum is to present the methodology for estimating the costs,

emission reductions, and secondary impacts3 associated with the final standards for sanitaryware 

sector of the clay ceramics source category. (For the final rulemaking, only the impacts 

estimates for sanitaryware sources were updated from the proposed estimates, as there are no 

major sources in the ceramic tile industry sector.) A background discussion of the types of costs, 

emission reductions, and secondary impacts being estimated is provided in the memorandum 

Methodology and Assumptions Used to Estimate the Model Costs and Impacts of Clay Ceramics 

Air Pollution Control Devices for the Final Rule (Holloway and Raymond, 2015). 

The standards include health-based standards for acid gases (HF and HCl) and maximum 

achievable control technology (MACT) numeric emission limits for Hg, PM (as a surrogate for 

non-Hg HAP metals), and dioxins/furans for sources expected to emit those pollutants. The 

development of these standards and options are documented in two memoranda, Risk Assessment 

to Determine a Health-Based Emission Limitation for Acid Gases for the Clay Ceramics 

Manufacturing Source Category (Morris et al., 2014) and Maximum Achievable Control 

Technology (MACT) Floor Analysis for Clay Ceramics (Raymond and Sroka, 2015).

In developing the proposed standards, the EPA also considered “beyond-the-floor” 

options for Hg, PM (as a surrogate for non-Hg HAP metals), and dioxins/furans for all three 

industry sectors (sanitaryware, ceramic floor tile, and ceramic wall tile). Note that for the final 

rulemaking, the nationwide costs, emission reductions, and secondary impacts associated with 

the beyond-the-floor options were not recalculated from proposal, as the cost effectiveness of 

these options would not be significantly lower than at proposal. For the calculation of the 

nationwide costs, emission reductions, and secondary impacts associated with the beyond-thefloor options for non-Hg HAP metals and Hg at proposal, see Development of Cost and Emission 

Reduction Impacts for the Clay Ceramics NESHAP (Holloway and Raymond, 2014).

Section II of this memorandum shows the nationwide baseline emissions for the major 

sources in the clay ceramics industry. Section III describes the assessment of what air pollution 

control devices (APCD) would be needed for major source sanitaryware facilities to meet the 

proposed health-based standards. Section IV describes the analysis of what APCD would be 

needed for sanitaryware stacks to meet the proposed MACT standards and presents the 

nationwide costs, emission reductions, and secondary impacts associated with those APCD.

 2 A major source of HAP is a facility that has the potential to emit 10 tons per year (tpy) or more of any single HAP 

or 25 tpy or more of any combination of HAP. 3 The secondary impacts addressed in this memorandum include the following:

• Energy impacts: The annual amount of energy (in million British thermal units per year [MMBtu/yr]) 

needed to generate the electricity to operate the control devices used to comply with the proposed standards 

and beyond-the-floor options.

• Secondary emissions: The criteria air pollutant emissions—PM, PM2.5, carbon monoxide (CO), nitrogen 

oxides (NOx), and SO2—(in tpy) that result from the generation of electricity used to operate the control 

devices.

• Solid waste: The material (in tpy) captured by the control devices.
3

II. Baseline Emissions

The clay ceramics industry has several sources with varying amounts of available data 

and information about control devices to estimate baseline emissions. As such, the baseline 

emissions for sanitaryware sources were developed differently for different sources.

A. Sanitaryware Tunnel Kilns

For sanitaryware tunnel kilns, baseline emissions (tpy) were developed for HF, HCl, nonHg HAP metals, PM, PM2.5, Hg, and dioxin/furan TEQ. Test data were available for all of these 

pollutants for each kiln, so model emissions were not developed. The average lb/ton emissions

for each pollutant and kiln were multiplied by the kiln design capacity (tons per hour [tph]), then 

multiplied by 8,760 operating hours, then divided by 2,000 lb/ton to estimate the baseline 

emissions. The nationwide baseline emissions for PM2.5 were estimated as 48 percent of the 

baseline PM emissions. See Table 1 for the nationwide baseline emissions estimates for 

sanitaryware tunnel kilns.

Table 1. Nationwide Baseline Emissions Estimates for Sanitaryware Tunnel Kilns

APCD

Type Size Count

Nationwide Emissions (tpy)

HF HCl

Non-Hg 

HAP 

Metals PM PM2.5 Hg D/F TEQ

None & 

WS

Small & 

Large

8

[7 None; 

1 WS]

15.2 1.19 0.083 7.47 3.59 0.011 2.72E-07

B. Sanitaryware Glazing Operations

For sanitaryware glazing operations, baseline emissions (tpy) were developed for PM and 

PM2.5 for each APCD type (FF, WS, and water curtains [WC]). Test data were not available for 

all of the operating spray booths, so data from similar units (e.g., similar location, APCD, glaze 

spray rate) were used to estimate emissions for the units without data. Each unit’s lb/ton 

emissions value was multiplied by its glaze spray rate (in tph), then multiplied by the annual 

operating hours and divided by 2,000 lb/ton to estimate baseline emissions. The nationwide 

baseline emissions for PM2.5 were estimated as 48 percent of the baseline PM emissions. See 

Table 2 for the nationwide baseline emissions estimates for sanitaryware glazing operations.
4

Table 2. Nationwide Baseline Emissions Estimates for Sanitaryware Glazing Operations

Unit Type

APCD

Type Size Count

Nationwide Emissions (tpy)

PM PM2.5

Manual glaze application FF All 2 6.84 3.28

WS All 1 2.31 1.11

WC All 11 28.73 13.79

Manual glaze application total 37.88 18.18

Robot glaze application WS All 1 0.70 0.34

WC All 9 9.75 4.68

Robot glaze application total 10.46 5.02

Spray machine glaze application WC All 4 16.22 7.79

See Table 3 for the nationwide baseline emissions estimates for all sanitaryware unit 

types being regulated under the clay ceramics manufacturing final rule.

Table 3. Total Nationwide Baseline Emissions Estimates for Sanitaryware

Unit Type

Emissions (tpy)

HF HCl

Non-Hg 

HAP Metals PM PM2.5 SO2 Hg D/F TEQ

Sanitaryware Tunnel Kilns 15.2 1.19 0.083 7.47 3.59 0.011 2.72E-07

Sanitaryware Manual Glaze 

Application

37.9 18.2

Sanitaryware Spray Machine 

Glaze Application

16.2 7.79

Sanitaryware Robot Glaze 

Application

10.5 5.02

Sanitaryware Total 15.2 1.19 0.083 72.0 34.6 0 0.011 2.72E-07

III. Cost and Emission Reduction Estimates for Meeting Health-Based Standards

For the acid gases HF and HCl, a health-based emission limit was developed for acid 

gases under CAA section 112(d)(4). The rationale behind the standard is discussed in the 

preamble to the clay ceramics final rule. The development of the facility-level health-based 

emission limit, 600 tpy of HCl-equivalent, or 140 lb/hr of HCl-equivalent, is documented in the 

memorandum Risk Assessment to Determine a Health-Based Emission Limitation for Acid Gases 

for the Clay Ceramics Manufacturing Source Category (Morris et al., 2014).

The equivalency of HCl with HF is based on the chronic Reference Concentration (RfC) 

values for each of the acid gases. The RfC for HCl is 20 micrograms per cubic meter (μg/m3

)

and the RfC for HF is 14 μg/m3 (Morris et al., 2014). Therefore, the following equation can be 

used to calculate the HCl-equivalent emissions for an individual kiln:
5





 



















 = +

HF

HCl

i HCl HF RfC

RfC E E E

where:

Ei = HCl-equivalent emissions, lb/hr

EHCl = emissions of HCl, lb/hr

EHF = emissions of HF, lb/hr

RfCHCl = reference concentration for HCl, 20 μg/m3

RfCHF = reference concentration for HF, 14 μg/m3

Test data are available for some of the kilns in the clay ceramics industry (see the 

memorandum Test Data Used in Clay Ceramics Manufacturing Final Rule (Raymond, 2015)). 

If test data were not available for all acid gas emissions (i.e., HF and HCl), emission factors were 

used to estimate emissions. This information was used in the equation above to calculate an 

HCl-equivalent value for each kiln. The HCl-equivalent values were summed for all kilns at a 

major source facility and then compared to the health-based emission limit.

As shown in Table 4, all major source clay ceramics facilities could meet the healthbased emission limit of 140 lb/hr of HCl-equivalent with current control configurations.

Table 4. Acid Gas Emissions and HCl-Equivalent Emissions for Major Source Kilns

Facility ID Company Name Facility Name HF (lb/hr)

HCl 

(lb/hr)

E (lb/hr) 

(Chronic)

KOHL-SC Kohler Co. Kohler, Spartanburg Plant 0.77 0.058 1.16

KOHL-TX Kohler Co. Kohler, Brownwood Plant 1.24 0.10 1.87

KOHL-WI Kohler Co. Kohler, Wisconsin Plant 0.29 0.017 0.43

IV. Cost and Emission Reduction Estimates for Meeting Hg, Non-Hg HAP Metals, and 

Dioxin/Furan TEQ Proposed Standards

There are only three sanitaryware facilities currently classified as major sources in the 

clay ceramics industry. There are five ceramic tile facilities that were major sources at the time 

of the 2008 and 2010 section 114 EPA surveys of the clay ceramics industry, but these facilities 

were recently re-classified as synthetic area sources due to the installation of new APCD.

4 These

five ceramic tile facilities would not be subject to the rule, so the impacts of requiring them to 

 4 A major source of HAP emissions is a source that has the potential to emit 10 tpy or more of any individual HAP 

or 25 tpy or more of any combination of HAP. A synthetic area source is a source that obtains a federally 

enforceable limit (e.g., in a title V permit) that reduces emissions below major source thresholds, by installing an 

APCD or taking a limit on their operating capacity, for example.
6

meet the limits were not updated from proposal. A summary of the sources at the facilities used 

for all remaining analyses in this memorandum is shown in Table 5 (Raymond, 2015). 

Table 5. Summary of Units at Major Sources

Source Type No. of Units No. of Unit Stacks

Sanitaryware First-fire Tunnel Kilns 11 7

Sanitaryware Manual Glaze Application 14 14

Sanitaryware Spray Machine Glaze Application 4 4

Sanitaryware Robot Glaze Application 10 10

The Clay Ceramics Manufacturing NESHAP includes MACT standards for Hg, PM (as a 

surrogate for non-Hg HAP metals), and dioxin/furan TEQ. As noted previously, test data were 

available for some kilns and glazing operations in the industry (as shown in Table 6). 

Table 6. Facilities with Available Test Data

Fac ID Fac ID Company City State Source Classification

203 KOHL-TX Kohler Brownwood TX Major

82 KOHL-SC Kohler Spartanburg SC Major

204 KOHL-WI Kohler Kohler WI Major

Data on PM emissions were available for about 55 percent of the sanitaryware tunnel 

kilns, 21 percent of the sanitaryware manual glaze booths, 75 percent of the sanitaryware spray 

machine booths, and 40 percent of the sanitaryware robot glaze booths. Data on Hg and non-Hg 

HAP metals emissions were available for about 45 percent of the sanitaryware tunnel kilns. Data 

on dioxin/furan TEQ emissions were available for about 45 percent of the sanitaryware tunnel 

kilns (Raymond, 2015). Therefore, rather than evaluating the impacts of the standards on a unitby-unit basis, as was done for the health-based emission limit, several assumptions were needed 

to evaluate the impacts on the whole industry. This analysis was completed in a series of three

steps, described in the remainder of this section.

Step 1: Compare Test Data to Emission Limits

The first step was to compare the data available to the emission limits to get an estimate 

of the percentage of kilns and glazing operations in the industry that could meet the limits with 

current APCD configurations. For all sanitaryware unit types, 100 percent of units were 

estimated to meet the MACT floor limits.

Step 2: Develop Estimate of Number of APCD Needed

For the next step, in addition to looking at the units with data, estimates for the units 

without data were developed to estimate the number of APCD needed for the units to meet the 
7

standards. For the units with no data available, the data from similar units (e.g., similar location, 

APCD, design capacity) were used to fill in the data gaps. Those units’ similar data were then 

compared to the proposed limits to see if the data would meet the limits or not. For those units 

with no data available and where data from similar units could not be used to fill in the gaps, the 

current control device of the unit was examined. For units with no control device, it was assumed 

that they could not meet the PM, Hg, and dioxin/furan TEQ limits. For units with WS, DIFF, or 

DLS/FF, it was assumed that they could meet the PM, Hg, and dioxin/furan TEQ limits. After 

each unit was evaluated to see if it could meet the limits, the percentage of units (with and 

without data) meeting the limits were calculated for PM, Hg, and dioxin/furan TEQ. These 

percentages were compared to the 100 percent previously presented in Step 1 of this section 

calculated for units with data to make sure they were similar. The ability of each unit to be able 

to meet the PM, Hg, and dioxin/furan TEQ limits determined the criteria for APCD to be 

installed or not (see Table 7).
8

Table 7. Scenarios for Sanitaryware Units

Unit Type Current APCD

Meets PM 

limit

Meets 

Hg limit

Meets D/F

TEQ limit APCD / Action Needed

Sanitaryware 

Tunnel Kilns

Wet Scrubber No No No Add FF and ACI-2

Wet Scrubber No No Yes Add FF and ACI-1-Hg

Wet Scrubber No Yes No Add FF and ACI-1-D/F

Wet Scrubber No Yes Yes Add FF

Wet Scrubber Yes No No Add FF and ACI-2

Wet Scrubber Yes No Yes Add FF and ACI-1-Hg

Wet Scrubber Yes Yes No Add FF and ACI-1-D/F

Wet Scrubber Yes Yes Yes No action

None No No No Install FF and ACI-2

None No No Yes Install FF and ACI-1-Hg

None No Yes No Install FF and ACI-1-D/F

None No Yes Yes Install FF

None Yes No No Install FF and ACI-2

None Yes No Yes Install FF and ACI-1-Hg

None Yes Yes No Install FF and ACI-1-D/F

None Yes Yes Yes No action

Sanitaryware 

Glazing

Water Curtain No n/a n/a Retrofit with FF

Water Curtain Yes n/a n/a No action

Fabric Filter No n/a n/a Retrofit with FF

Fabric Filter Yes n/a n/a No action

Wet Scrubber No n/a n/a Add FF

Wet Scrubber Yes n/a n/a No action

Install: installing a brand new piece of equipment

Retrofit: removing the existing equipment and installing new equipment

Add: keeping existing equipment in place and adding the new equipment to the existing control configuration

ACI-1: Activated Carbon Injection for Hg or D/F TEQ

ACI-2: Activated Carbon Injection for Hg and D/F TEQ

n/a: not applicable 

All sanitaryware tunnel kilns and glazing operations are projected to meet the limits with 

current controls; therefore, there are no APCD expected to be installed or retrofit.

Step 3: Calculate the Nationwide Costs, Emission Reductions, and Secondary Impacts

The final step in estimating nationwide costs and impacts would be to apply model 

APCD costs, emission reductions, and secondary impacts to the estimated counts of APCD 

needed. However, because no APCD are expected to be installed, the nationwide costs, emission 

reductions, and secondary impacts attributed to APCD are all zero.
9

V. References

Holloway, T. and G. Raymond. 2015. Methodology and Assumptions Used to Estimate the 

Model Costs and Impacts of Clay Ceramics Air Pollution Control Devices for the Final Rule. 

Memorandum from Thomas Holloway and Gabrielle Raymond, RTI International, to Sharon 

Nizich, EPA/OAQPS/SPPD. September 24, 2015.

Morris, M., T. Palma, and C. Sarsony. 2014. Risk Assessment to Determine a Health-Based 

Emission Limitation for Acid Gases for the Clay Ceramics Manufacturing Source Category. 

Memorandum from Mark Morris, Ted Palma, and Chris Sarsony, EPA/OAQPS/HEID, to 

Docket EPA-HQ-OAR-2013-0291. May 19, 2014. Docket Item No. EPA-HQ-OAR-2013-

0290-0213.

Raymond, G., and K. Sroka. 2015. Final Maximum Achievable Control Technology (MACT) 

Floor Analysis for Clay Ceramics. Memorandum from Gabrielle Raymond and Kristin 

Sroka, RTI International, to Sharon Nizich, EPA/OAQPS/SPPD. September 24, 2015.

Raymond, G. 2014. Updated Inventory Database and Documentation for Clay Ceramics

Proposed Rule. Memorandum from Gabrielle Raymond, RTI International, to Jeff Telander, 

EPA/OAQPS/SPPD. November 6, 2014. Docket Item EPA-HQ-OAR-2013-0290-0222.

Raymond, G. 2015. Test Data Used in Clay Ceramics Manufacturing Final Rule. Memorandum 

from Gabrielle Raymond, RTI International, to Sharon Nizich, EPA/OAQPS/SPPD. 

September 24, 2015.