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Subpart PPP—National Emission Standards for Hazardous Air 

Pollutant Emissions for Polyether Polyols Production

Table of Contents

§63.1420 Applicability and designation of affected sources.

§63.1421 Implementation and enforcement.

§63.1422 Compliance dates and relationship of this rule to 

existing applicable rules.

§63.1423 Definitions.

§63.1424 Emission standards.

§63.1425 Process vent control requirements.

§63.1426 Process vent requirements for determining organic HAP 

concentration, control efficiency, and aggregated organic HAP 

emission reduction for a PMPU.

§63.1427 Process vent requirements for processes using extended 

cookout as an epoxide emission reduction technique.

§63.1428 Process vent requirements for group determination of 

PMPUs using a nonepoxide organic HAP to make or modify the 

product.

§63.1429 Process vent monitoring requirements.

§63.1430 Process vent reporting and recordkeeping requirements.

§63.1431 Process vent annual epoxides emission factor plan 

requirements.

§63.1432 Storage vessel provisions.

§63.1433 Wastewater provisions.

§63.1434 Equipment leak provisions.

§63.1435 Heat exchanger provisions.

§63.1436 [Reserved]

§63.1437 Additional requirements for performance testing.

§63.1438 Parameter monitoring levels and excursions.

§63.1439 General recordkeeping and reporting provisions.

Tables to Subpart PPP of Part 63

Table 1 of Subpart PPP of Part 63-Applicability of General 

Provisions to Subpart PPP Affected Sources

Table 2 of Subpart PPP of Part 63-Applicability of General HON 

Provisions to Subpart PPP Affected Sources

Table 3 to Subpart PPP of Part 63-Group 1 Storage Vessels at 

Existing and New Affected Sources

Table 4 to Subpart PPP of Part 63-Known Organic HAP From 

Polyether Polyol Products
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Table 5 to Subpart PPP of Part 63-Process Vents From Batch Unit 

Operations--Monitoring, Recordkeeping, and Reporting 

Requirements

Table 6 to Subpart PPP of Part 63-Process Vents From Continuous 

Unit Operations--Monitoring, Recordkeeping, and Reporting 

Requirements

Table 7 to Subpart PPP of Part 63-Operating Parameters For Which 

Monitoring Levels Are Required to be Established For Process 

Vent StreamsProcess Vents From Continuous Unit Operations--

Monitoring, Recordkeeping, and Reporting Requirements

Table 8 to Subpart PPP of Part 63-Routine Reports Required by 

This Subpart

§63.1420 Applicability and designation of affected sources.

(a) Definition of affected source. The provisions of this 

subpart apply to each affected source. Affected sources are 

described in paragraphs (a)(1) through (4) of this section.

(1) An affected source is either an existing affected 

source or a new affected source. Existing affected source is 

defined in paragraph (a)(2) of this section, and new affected 

source is defined in paragraph (a)(3) of this section.

(2) An existing affected source is defined as the group of 

one or more polyether polyol manufacturing process units (PMPUs) 

and associated equipment, as listed in paragraph (a)(4) of this 

section, that is not part of a new affected source, as defined 

in paragraph (a)(3) of this section, and that is located at a 

plant site that is a major source.

(3) A new affected source is defined as a source that meets 

the criteria of paragraph (a)(3)(i), (ii), or (iii) of this 
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section. The situation described in paragraph (a)(3)(i) of this 

section is distinct from those situations described in 

paragraphs (a)(3)(ii) and (iii) of this section.

(i) At a site without organic HAP emission points before 

September 4, 1997 (i.e., a “greenfield” site), the group of one 

or more PMPUs and associated equipment, as listed in paragraph 

(a)(4) of this section, that is part of a major source, and on 

which construction for the PMPU(s) commenced after September 4, 

1997;

(ii) The group of one or more PMPUs meeting the criteria in 

paragraph (g)(1)(i) of this section; or

(iii) A reconstructed affected source meeting the criteria 

in paragraph (g)(2)(i) of this section.

(4) The affected source also includes the emission points 

and equipment components specified in paragraphs (a)(4)(i) 

through (vi) of this section that are associated with a PMPU (or 

a group of PMPUs) making up an affected source, as defined in 

§63.1423.

(i) Each waste management unit.

(ii) Maintenance wastewater.

(iii) Each heat exchange system.

(iv) Equipment Components required by or utilized as a 

method of compliance with this subpart, which may include 

control techniques and recovery devices.
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(v) Product finishing operation.

(vi) Each feed or catalyst operation.

(b) PMPUs without organic HAP. The owner or operator of a 

PMPU that is part of an affected source, as defined in paragraph 

(a) of this section, but that does not use or manufacture any 

organic HAP during the production of one or more products is 

only subject to the provisions of this subpart as specified in 

paragraph (b)(1) or (2) of this section, as applicable. Products 

or raw material(s) containing organic HAP as impurities only are 

not considered organic HAP for the purposes of this paragraph.

(1) If an organic HAP is not used or manufactured in the 

production of polyether polyols, the PMPU is not subject to any 

provisions of this subpart, except that the owner or operator 

shall comply with either paragraph (b)(1)(i) or (ii) of this 

section. The owner or operator is not required to comply with 

the provisions of 40 CFR part 63, subpart A (the General 

Provisions) for that PMPU.

(i) Retain information, data, and analyses used to document 

the basis for the determination that the PMPU does not use or 

manufacture any organic HAP. Types of information that could 

document this determination include, but are not limited to, 

records of chemicals purchased for the process, analyses of 

process stream composition, engineering calculations, or process 

knowledge.
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(ii) When requested by the Administrator, demonstrate that 

the PMPU does not use or manufacture any organic HAP.

(2) If an organic HAP is used or manufactured in the 

production of polyether polyols, but an organic HAP is not used 

in the production of one or more products that are not polyether 

polyols, the PMPU is not subject to any provision of this 

subpart other than paragraph (b)(1)(i) or (ii) of this section 

during the production of the non-polyether polyol products that 

do not use or manufacture any organic HAP.

(c) Emission points included in the affected source but not 

subject to the provisions of this subpart. The affected source 

includes the emission points listed in paragraphs (c)(1) through 

(12) of this section, but these emission points are not subject 

to the requirements of this subpart or the provisions of 40 CFR 

part 63, subpart A.

(1) Components and Eequipment that does not contain organic 

HAP or that contains organic HAP as impurities only and is are 

located at a PMPU that is part of an affected source.

(2) Stormwater managed in segregated sewers.

(3) Water from fire-fighting and deluge systems in 

segregated sewers.

(4) Spills.

(5) Water from safety showers.

(6) Water from testing of deluge systems.
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(7) Water from testing of firefighting systems.

(8) Vessels that store and/or handle material that contains 

no organic HAP or organic HAP as impurities only.

(9) Equipment that operates in organic HAP service for less 

than 300 hours during the calendar year.

(10) Loading racks, loading arms, or loading hoses that 

only transfer liquids containing HAP as impurities.

(11) Loading racks, loading arms, or loading hoses that 

vapor balance during all loading operations.

(12) Utility fluids, such as heat transfer fluids.

(d) Processes exempted excluded from the affected source. 

The processes specified in paragraphs (d)(1) through (3) of this 

section are not part of the affected source and are exempted 

fromnot subject to the requirements of both this subpart and 

subpart A of this part.

(1) Research and development facilities.

(2) Solvent reclamation, recovery, or recycling operations 

at hazardous waste treatment, storage, and disposal facilities 

(TSDF) requiring a permit under 40 CFR part 270 that are not 

part of a PMPU to which this subpart applies.

(3) Reactions or processing that occur after the epoxide 

polymerization is complete and after all catalyst removal steps, 

if any, are complete.
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(e) Primary product determination and applicability. An 

owner or operator of a process unit that produces or plans to 

produce a polyether polyol shall determine if the process unit 

is subject to this subpart in accordance with this paragraph.

(1) Initial primary product determination. The owner or 

operator shall initially determine the primary product of each 

process unit in accordance with paragraphs (e)(1)(i) through 

(iii) of this section.

(i) If a process unit manufactures only one product, then 

that product shall represent the primary product of the process 

unit.

(ii) If a process unit produces more than one intended 

product at the same time, the primary product shall be 

determined in accordance with paragraph (e)(1)(ii)(A) or (B) of 

this section.

(A) The product for which the process unit has the greatest 

annual design capacity on a mass basis shall represent the 

primary product of the process unit, or

(B) If a process unit has the same maximum annual design 

capacity on a mass basis for two or more products and if one of 

those products is a polyether polyol, then the polyether polyol 

shall represent the primary product of the process unit.

(iii) If a process unit is designed and operated as a 

flexible operation unit, the primary product shall be determined 
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as specified in paragraph (e)(1)(iii)(A) or (B) of this section 

based on the anticipated operations for the 5 years following 

September 4, 1997 for existing process units, or for the first 

year after the process unit begins production of any product for 

the new process units. If operations cannot be anticipated 

sufficiently to allow the determination of the primary product 

for the specified period, applicability shall be determined in 

accordance with paragraph (e)(2) of this section.

(A) If the flexible operation unit will manufacture one 

product for the greatest operating time over the specified 5-

year period for existing process units, or the specified 1-year 

period for new process units, then that product shall represent 

the primary product of the flexible operation unit.

(B) If the flexible operation unit will manufacture 

multiple products equally based on operating time, then the 

product with the greatest expected production on a mass basis 

over the specified 5-year period for existing process units, or 

the specified 1-year period for new process units shall 

represent the primary product of the flexible operation unit.

(iv) If, according to paragraph (e)(1)(i), (ii), or (iii) 

of this section, the primary product of a process unit is a 

polyether polyol, then that process unit shall be designated as 

a PMPU. If the plant site is a major source, that PMPU and 

associated equipment, as listed in paragraph (a)(4) of this 
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section, is either an affected source or part of an affected 

source comprised of one or more other PMPUs and associated 

equipment, as listed in paragraph (a)(4) of this section, and 

subject to this subpart. If the primary product of a process 

unit is not a polyether polyol, then that process unit is not a 

PMPU.

(2) Provisions if primary product cannot be determined. If 

the primary product cannot be determined for a flexible 

operation unit in accordance with paragraph (e)(1)(iii) of this 

section, applicability shall be determined in accordance with 

this paragraph.

(i) If the owner or operator can determine that a polyether 

polyol is not the primary product, then that flexible operation 

unit is not a PMPU.

(ii) If the owner or operator cannot determine that a 

polyether polyol is not the primary product as specified in 

paragraph (e)(2)(i) of this section, applicability shall be 

determined in accordance with paragraph (e)(2)(ii)(A) or (B) of 

this section.

(A) If the flexible operation unit is an existing process 

unit, the flexible operation unit shall be designated as a PMPU 

if a polyether polyol was produced for 5 percent or greater of 

the total operating time of the flexible operation unit since 

September 4, 1997.
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(B) If the flexible operation unit is a new process unit, 

the flexible operation unit shall be designated as a PMPU if the 

owner or operator anticipates that a polyether polyol will be 

manufactured in the flexible operation unit at any time in the 

first year after the date the unit begins production of any 

product.

(3) Annual applicability determination for non-PMPUs that 

have produced a polyether polyol. Once per year beginning June 

1, 2004, the owner or operator of each flexible operation unit 

that is not designated as a PMPU, but that has produced a 

polyether polyol at any time in the preceding 5-year period or 

since the date that the unit began production of any product, 

whichever is shorter, shall perform the evaluation described in 

paragraphs (e)(3)(i) through (iii) of this section. However, an 

owner or operator that does not intend to produce any elastomer 

product in the future, in accordance with paragraph (e)(9) of 

this section, is not required to perform the evaluation 

described in paragraphs (e)(3)(i) through (iii) of this section.

(i) For each product produced in the flexible operation 

unit, the owner or operator shall calculate the percentage of 

total operating time over which the product was produced during 

the preceding 5-year period.
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(ii) The owner or operator shall identify the primary 

product as the product with the highest percentage of total 

operating time for the preceding 5-year period.

(iii) If the primary product identified in paragraph 

(e)(3)(ii) is a polyether polyol, the flexible operation unit 

shall be designated as a PMPU. The owner or operator shall 

notify the Administrator no later than 45 days after determining 

that the flexible operation unit is a PMPU, and shall comply 

with the requirements of this subpart in accordance with 

paragraph (g)(1) of this section for the flexible operation 

unit.

(4) Applicability determination for non-PMPUs that have not 

produced a polyether polyol. The owner or operator that 

anticipates the production of a polyether polyol in a process 

unit that is not designated as a PMPU, and in which no polyether 

polyol products have been produced in the previous 5-year period 

or since the date that the process unit began production of any 

product, whichever is shorter, shall use the procedures in 

paragraph (e)(1) or (2) of this section to determine if the 

process unit is designated as a PMPU, with the exception that 

for existing process units, owners or operators shall project 

production for the 5 years following the date that the owner or 

operator anticipates initiating the production of a polyether 

polyol, instead of the 5 years following September 4, 1997. If 
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the unit is designated as a PMPU, the owner or operator shall 

comply in accordance with paragraph (g)(1) of this section.

(5) Applicability of requirements for PMPUs that are 

flexible operation units. The owner or operator of PMPUs that 

are flexible operation units shall comply with the provisions of 

this subpart in accordance with paragraphs (e)(5)(i) through 

(iii) of this section.

(i) Control requirements. The owner or operator shall 

comply with the control requirements of this subpart in 

accordance with paragraphs (e)(5)(i)(A) and (B) of this section.

(A) During periods when the PMPU produces polyether 

polyols, the owner or operator shall comply with the provisions 

of this subpart.

(B) During periods when the PMPU produces products other 

than polyether polyols, the owner or operator is not required to 

install additional combustion, recovery, or recapture devices 

(to otherwise demonstrate compliance). However, the owner or 

operator shall continue to operate any existing combustion, 

recovery, or recapture devices that are required for compliance 

during the production of polyether polyols, with the exceptions 

provided in paragraph (e)(5)(iv) of this section. If extended 

cookout (ECO) is the control technique chosen for epoxide 

emission reduction, then ECO or a control technique providing an 

equivalent reduction in epoxide emissions should continue to be 
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used for epoxide emission reduction, if the non-polyether polyol 

being produced uses epoxide monomers.

(ii) Monitoring requirements. The owner or operator shall 

comply with the monitoring requirements of this subpart in 

accordance with paragraphs (e)(5)(ii)(A) and (B) of this 

section, and paragraph (e)(5)(ii)(C) of this section if 

applicable.

(A) The owner or operator shall establish a single 

parameter monitoring level (for each parameter required to be 

monitored at each device subject to monitoring requirements) in 

accordance with §63.1438(a) based on emission point and control 

technique characteristics when polyether polyol is being 

produced.

(B) The owner or operator shall monitor each parameter at 

each device subject to monitoring requirements at all times 

(during periods when the PMPU produces polyether polyols, and 

during periods when the PMPU produces products other than 

polyether polyols), with the exceptions provided in paragraph 

(e)(5)(iv) of this section.

(C) If ECO is used to reduce epoxide emissions, a parameter 

monitoring level shall be established for the production of nonpolyether polyol products as the average of the established 

parameter levels for all product classes produced. During 

periods when products other than polyether polyols are produced, 
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the ECO shall be performed so that the parameter monitoring 

level established for the production of non-polyether polyol 

products is maintained when the ECO is used as a control 

technique.

(iii) Group determinations. For emission points where the 

owner or operator is required to determine if the emission point 

is Group 1 according the definitions in §63.1423 (storage 

vessels, process vents for nonepoxide organic HAP emissions used 

to make or modify the product, and wastewater), the owner or 

operator shall determine the group status based on emission 

point characteristics when polyether polyol is being 

manufactured. Group 1 emission points shall be controlled in 

accordance with paragraph (e)(5)(i) of this section.

(iv) Exceptions. During periods when products described in 

paragraphs (e)(5)(iv)(A) and (B) of this section are produced, 

the owner or operator is not required to comply with the 

provisions of this subpart.

(A) Products in which no organic HAP is used or 

manufactured, provided that the owner or operator comply with 

paragraph (b)(2) of this section.

(B) Products that make the PMPU subject to 40 CFR part 63, 

subpart GGG (Pharmaceuticals Production NESHAP).

(6)–(7) [Reserved]
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(8) Requirements for flexible process units that are not 

PMPUs. If it is determined that a process unit is not subject to 

this subpart, the owner or operator shall either retain all 

information, data, and analysis used to document the basis for 

the determination that the process unit is not a PMPU, or, when 

requested by the Administrator, demonstrate that the process 

unit is not a PMPU.

(9) PMPUs terminating production of all polyether polyols. 

If a PMPU terminates the production of all polyether polyols, 

and the owner or operator does not anticipate the production of 

any polyether polyols in the future in that PMPU, the process 

unit is no longer a PMPU and is not subject to this subpart 

after notification is made to the Administrator. This 

notification shall be accompanied by a rationale for why it is 

anticipated that no polyether polyols will be produced in the 

process unit in the future.

(10) Redetermination of applicability to PMPUs that are 

flexible operation units. Whenever changes in production occur 

that could reasonably be expected to change the primary product 

of a PMPU that is operating as a flexible operation unit from a 

polyether polyol to a product that would make the process unit 

subject to another subpart of this part, the owner or operator 

shall reevaluate the primary product, in accordance with 

paragraphs (e)(3)(i) and (ii) of this section. If the conditions 
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in paragraphs (e)(10)(i) through (iii) of this section are met, 

the flexible operation unit shall no longer be designated as a 

PMPU after the compliance date of the other subpart, and shall 

no longer be subject to the provisions of this subpart after the 

date that the process unit is required to be in compliance with 

the provisions of the other subpart. If the conditions in 

paragraphs (e)(10)(i) through (iii) of this section are not met, 

the flexible operation unit shall continue to be considered a 

PMPU and subject to the requirements of this subpart.

(i) The product identified as the primary product is not 

polyether polyol;

(ii) The production of the product identified as the 

primary product is subject to another subpart of this part; and

(iii) The owner or operator submits a notification to the 

Administrator of the pending change in applicability.

(f) Storage vessel ownership determination. The owner or 

operator shall follow the procedures specified in paragraphs 

(f)(1) through (7) of this section to determine to which process 

unit a storage vessel shall be assigned.

(1) If a storage vessel is already subject to another 

subpart of 40 CFR part 63 (National Emission Standards for 

Hazardous Air Pollutants for Source Categories) on June 1, 1999, 

that storage vessel shall be assigned to the process unit 
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subject to the other subpart, and none of the other provisions 

in this subpart shall apply to that storage vessel.

(2) If a storage vessel is dedicated to a single process 

unit, the storage vessel shall be assigned to that process unit.

(3) If a storage vessel is shared among process units, then 

the storage vessel shall be assigned to that process unit 

located on the same plant site as the storage vessel that has 

the greatest input into or output from the storage vessel (i.e., 

the process unit that has the predominant use of the storage 

vessel.)

(4) If predominant use cannot be determined for a storage 

vessel that is shared among process units and if only one of 

those process units is a PMPU subject to this subpart, the 

storage vessel shall be assigned to that PMPU.

(5) If predominant use cannot be determined for a storage 

vessel that is shared among process units and if more than one 

of the process units are PMPUs that have different primary 

products and that are subject to this subpart, then the owner or 

operator shall assign the storage vessel to any one of the PMPUs 

sharing the storage vessel.

(6) If the predominant use of a storage vessel varies from 

year to year, then predominant use shall be determined based on 

the utilization that occurred during the year preceding June 1, 

1999 or based on the expected utilization for the 5 years 
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following June 1, 1999 for existing affected sources, whichever 

is more representative of the expected operations for that 

storage vessel, and based on the expected utilization for the 5 

years after initial start-up for new affected sources. The 

determination of predominant use shall be reported in the 

Notification of Compliance Status, as required by 

§63.1439(e)(5)(v).

(7) Where a storage vessel is located at a major source 

that includes one or more process units which place material 

into or receive material from the storage vessel, but the 

storage vessel is located in a tank farm (including a marine 

tank farm), the applicability of this subpart shall be 

determined according to the provisions in paragraphs (f)(7)(i) 

through (iv) of this section.

(i) The storage vessel may only be assigned to a process 

unit that utilizes the storage vessel and does not have an 

intervening storage vessel for that product (or raw materials, 

as appropriate). With respect to any process unit, an 

intervening storage vessel means a storage vessel connected by 

hard-piping to both the process unit and the storage vessel in 

the tank farm so that product or raw material entering or 

leaving the process unit flows into (or from) the intervening 

storage vessel and does not flow directly into (or from) the 

storage vessel in the tank farm.
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(ii) If there is no process unit at the major source that 

meets the criteria of paragraph (f)(7)(i) of this section with 

respect to a storage vessel, this subpart does not apply to the 

storage vessel.

(iii) If there is only one process unit at the major source 

that meets the criteria of paragraph (f)(7)(i) of this section 

with respect to a storage vessel, the storage vessel shall be 

assigned to that process unit.

(iv) If there are two or more process units at the major 

source that meet the criteria of paragraph (f)(7)(i) of this 

section with respect to a storage vessel, the storage vessel 

shall be assigned to one of those process units according to the 

provisions of paragraphs (f)(3) through (6) of this section. The 

predominant use shall be determined among only those process 

units that meet the criteria of paragraph (f)(7)(i) of this 

section.

(8) If the storage vessel begins receiving material from 

(or sending material to) a process unit that was not included in 

the initial determination, or ceases to receive material from 

(or send material to) a process unit that was included in the 

initial determination, the owner or operator shall reevaluate 

the applicability of this subpart to that storage vessel.
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(g) Changes or additions to plant sites. The provisions of 

this paragraph apply to the owner or operator that changes or 

adds to their plant site or affected source.

(1) Adding a PMPU to a plant site. The provisions of 

paragraphs (g)(1)(i) and (ii) of this section apply to the owner 

or operator that adds one or more PMPUs to a plant site. A PMPU 

may be added to a plant site by constructing or reconstructing a 

process unit to produce polyether polyols. A PMPU may also be 

added to a plant site due to changes in production (anticipated 

production or actual past production) such that a polyether 

polyol becomes the primary product of a process unit that was 

not previously a PMPU.

(i) If a group of one or more PMPUs is added to a plant 

site, the added group of one or more PMPUs and their associated 

equipment, as listed in paragraph (a)(4) of this section, shall 

be a new affected source and shall comply with the requirements 

for a new affected source in this subpart upon initial start-up 

or by June 1, 1999, whichever is later, if the added group of 

one or more PMPUs meets the criteria specified in paragraph 

(g)(1)(i)(A) of this section and either meets the criteria in 

paragraph (g)(1)(i)(B) or (C) of this section.

(A) The process units are new process units, as defined in 

§63.1423.
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(B) The added group of one or more PMPUs and associated 

equipment, as listed in paragraph (a)(4) of this section, has 

the potential to emit 10 tons per year (9.1 megagrams per year) 

or more of any organic HAP or 25 tons per year (22.7 megagrams 

per year) or more of any combination of organic HAP, and 

polyether polyols are currently produced at the plant site as 

the primary product of an affected source.

(C) A polyether polyol is not currently produced at the 

plant site as the primary product of an affected source, and the 

plant site meets, or after the addition is constructed will 

meet, the General Provisions' definition of a major source in 

§63.2.

(ii) If a group of one or more PMPUs is added to a plant 

site, and the added group of one or more PMPUs does not meet the 

criteria specified in paragraph (g)(1)(i)(A) of this section and 

one of the criteria specified in either paragraph (g)(1)(i)(B) 

or (C) of this section, and the plant site meets, or after the 

addition will meet, the definition of a major source, the owner 

or operator of the added group of one or more PMPUs and 

associated equipment, as listed in paragraph (a)(4) of this 

section, shall comply with the requirements for an existing 

affected source in this subpart upon initial start-up; by June 

1, 2002; or by 6 months after notifying the Administrator that a 
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process unit has been designated as a PMPU (in accordance with 

paragraph (g)(3) of this section), whichever is later.

(2) Adding emission points or making process changes to 

existing affected sources. The provisions of paragraphs 

(g)(2)(i), (ii), and (iii) of this section apply to the owner or 

operator that adds emission points or makes process changes to 

an existing affected source.

(i) If any components are replaced at an existing affected 

source such that the criteria specified in paragraphs 

(g)(2)(i)(A) and (B) of this section are met, the entire 

affected source shall be a new affected source and shall comply 

with the requirements for a new affected source upon initial 

start-up or by June 1, 1999, whichever is later.

(A) The replacement of components meets the definition of 

reconstruction in §63.1423(b). For purposes of determining 

whether the fixed capital cost of the new components exceeds 50 

percent of the fixed capital cost that would be required to 

construct an entire affected source, the equivalent capital cost 

shall be the entire potentially affected source; and

(B) Such reconstruction commenced after September 4, 1997.

(ii) If any components are replaced at an existing affected 

source such that the criteria specified in paragraphs 

(g)(2)(i)(A) and (B) of this section are not met and that 

replacement of components creates one or more emission points 
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(i.e., either newly created Group 1 emission points or emission 

points that change from Group 2 to Group 1) or causes any other 

emission point to be added (i.e., Group 2 emission points, heat 

exchange systems subject to §63.1435, or equipment leak 

components subject §63.1434), the resulting emission point(s) 

shall be subject to the applicable requirements for an existing 

affected source. The resulting emission point(s) shall be in 

compliance upon initial start-up or by the appropriate 

compliance date specified in §63.1422 (i.e., December 1, 1999 

for most equipment leak components subject to §63.1434, and June 

1, 2002 for emission points other than equipment leaks), 

whichever is later.

(iii) If an addition or process change (not including a 

process change that solely replaces components) is made that 

creates one or more Group 1 emission points (i.e., either newly 

created Group 1 emission points or emission points that change 

group status from Group 2 to Group 1) or causes any other 

emission point to be added (i.e., Group 2 emission points, heat 

exchange systems subject to §63.1435, or equipment leak 

components subject to §63.1434), the resulting emission point(s) 

shall be subject to the applicable requirements for an existing 

affected source. The resulting emission point(s) shall be in 

compliance by initial start-up or by the appropriate compliance 

date specified in §63.1422 (i.e., December 1, 1999 for most 
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equipment leak components subject to §63.1434, and June 1, 2002 

for emission points other than equipment leaks), whichever is 

later.

(3) Determining what are and are not process changes. For 

purposes of paragraph (g) of this section, examples of process 

changes include, but are not limited to, additions in process 

equipment resulting in changes in production capacity; 

production of a product outside the scope of the compliance 

demonstration; or whenever there is a replacement, removal, or 

addition of recovery equipment. For purposes of paragraph (g) of 

this section, process changes do not include: process upsets, 

unintentional temporary process changes, and changes that do not 

alter the equipment configuration and operating conditions.

(4) Reporting requirements for owners or operators that 

change or add to their plant site or affected source. An owner 

or operator that changes or adds to their plant site or affected 

source, as discussed in paragraphs (g)(1) and (g)(2) of this 

section, shall submit a report as specified in 

§63.1439(e)(7)(iii).

(h) Applicability of this subpart during periods of startup, shutdown, malfunction, or non-operation. Paragraphs (h)(1) 

through (4) of this section shall be followed during periods of 

start-up, shutdown, malfunction, and non-operation of the 

affected source or any part thereof.
Page 25 of 262

(1) The emission limitations set forth in this subpart and 

the emission limitations referred to in this subpart shall apply 

at all times except during periods of nonoperation of the 

affected source (or specific portion thereof) resulting in 

cessation of the emissions to which this subpart applies. These 

emission limitations shall not apply during periods of start-up, 

shutdown, or malfunction, except as provided in paragraphs 

(h)(3) and (4) of this section. However, if a start-up, 

shutdown, malfunction, or period of nonoperation of one portion 

of an affected source does not affect the ability of a 

particular emission point to comply with the emission 

limitations to which it is subject, then that emission point 

shall still be required to comply with the applicable emission 

limitations of this subpart during the start-up, shutdown, 

malfunction, or period of nonoperation. For example, if there is 

an overpressure in the reactor area, a storage vessel that is 

part of the affected source would still be required to be 

controlled in accordance with the storage tank provisions in 

§63.1432. Similarly, the degassing of a storage vessel would not 

affect the ability of a process vent to meet the emission 

limitations for process vents in §§63.1425 through 63.1430.

(2) The emission limitations set forth in 40 CFR part 63, 

subpart H, as referred to in the equipment leak provisions in 

§63.1434, shall apply at all times except during periods of non-
Page 26 of 262

operation of the affected source (or specific portion thereof) 

in which the lines are drained and depressurized resulting in 

cessation of the emissions to which §63.1434 applies, or during 

periods of start-up, shutdown, malfunction, or process unit 

shutdown (as defined in §63.161).

(3) The owner or operator shall not shut down items of 

equipment that are required or utilized for compliance with this 

subpart during periods of start-up, shutdown, or malfunction 

during times when emissions (or, where applicable, wastewater 

streams or residuals) are being routed to such items of 

equipment if the shutdown would contravene requirements 

applicable to such items of equipment. This paragraph does not 

apply if the item of equipment is malfunctioning. This paragraph 

also does not apply if the owner or operator shuts down the 

compliance equipment (other than monitoring systems) to avoid 

damage due to a contemporaneous start-up, shutdown, or 

malfunction of the affected source or portion thereof. If the 

owner or operator has reason to believe that monitoring 

equipment would be damaged due to a contemporaneous start-up, 

shutdown, or malfunction of the affected source or portion 

thereof, the owner or operator shall provide documentation 

supporting such a claim in the Precompliance Report or in a 

supplement to the Precompliance Report, as provided for in 

§63.1439(e)(4). Once approved by the Administrator in accordance 
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with §63.1439(e)(4)(vii), the provision for ceasing to collect, 

during a start-up, shutdown, or malfunction, monitoring data 

that would otherwise be required by the provisions of this 

subpart shall be incorporated into the start-up, shutdown, 

malfunction plan for that affected source, as stated in 

§63.1439(b)(1).

(4) During start-ups, shutdowns, and malfunctions when the 

emission limitations of this subpart do not apply pursuant to 

paragraphs (h)(1) through (3) of this section, the owner or 

operator shall implement, to the extent reasonably available, 

measures to prevent or minimize excess emissions to the extent 

practical. For purposes of this paragraph, the term “excess 

emissions” means emissions greater than those allowed by the 

emissions limitation which would apply during operational 

periods other than start-up, shutdown, and malfunction. The 

measures to be taken shall be identified in the applicable 

start-up, shutdown, and malfunction plan, and may include, but 

are not limited to, air pollution control technologies, recovery 

technologies, work practices, pollution prevention, monitoring, 

and/or changes in the manner of operation of the affected 

source. Use of back-up control techniques is not required, but 

is allowed, if available.General duty. At all times, the owner 

or operator must operate and maintain any affected source, 

including associated air pollution control equipment and 
Page 28 of 262

monitoring equipment, in a manner consistent with safety and 

good air pollution control practices for minimizing emissions. 

The general duty to minimize emissions does not require the 

owner or operator to make any further efforts to reduce 

emissions if levels required by the applicable standard have 

been achieved. Determination of whether a source is operating in 

compliance with operation and maintenance requirements will be 

based on information available to the Administrator, which may 

include, but is not limited to, monitoring results, review of 

operation and maintenance procedures, review of operation and 

maintenance records, and inspection of the source.

(i) Affirmative defense for violation of emission standards 

during malfunction. In response to an action to enforce the 

standards set forth in this subpart, the owner or operator may 

assert an affirmative defense to a claim for civil penalties for 

violations of such standards that are caused by malfunction, as 

defined at §63.2. Appropriate penalties may be assessed if the 

owner or operator fails to meet their burden of proving all of 

the requirements in the affirmative defense. The affirmative 

defense shall not be available for claims for injunctive relief.

(1) Assertion of affirmative defense. To establish the 

affirmative defense in any action to enforce such a standard, 

the owner or operator must timely meet the reporting 
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requirements in paragraph (i)(2) of this section, and must prove 

by a preponderance of evidence that:

(i) The violation: 

(A) Was caused by a sudden, infrequent, and unavoidable 

failure of air pollution control equipment, process equipment, 

or a process to operate in a normal or usual manner, and 

(B) Could not have been prevented through careful planning, 

proper design or better operation and maintenance practices; and

(C) Did not stem from any activity or event that could have 

been foreseen and avoided, or planned for; and

(D) Was not part of a recurring pattern indicative of 

inadequate design, operation, or maintenance; and

(ii) Repairs were made as expeditiously as possible when a 

violation occurred; and

(iii) The frequency, amount, and duration of the violation 

(including any bypass) were minimized to the maximum extent 

practicable; and

(iv) If the violation resulted from a bypass of control 

equipment or a process, then the bypass was unavoidable to 

prevent loss of life, personal injury, or severe property 

damage; and

(v) All possible steps were taken to minimize the impact of 

the violation on ambient air quality, the environment and human 

health; and
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(vi) All emissions monitoring and control systems were kept 

in operation if at all possible, consistent with safety and good 

air pollution control practices; and

(vii) All of the actions in response to the violation were 

documented by properly signed, contemporaneous operating logs; 

and

(viii) At all times, the affected source was operated in a 

manner consistent with good practices for minimizing emissions; 

and

(ix) A written root cause analysis has been prepared, the 

purpose of which is to determine, correct, and eliminate the 

primary causes of the malfunction and the violation resulting 

from the malfunction event at issue. The analysis shall also 

specify, using best monitoring methods and engineering judgment, 

the amount of any emissions that were the result of the 

malfunction.

(2) Report. The owner or operator seeking to assert an 

affirmative defense shall submit a written report to the 

Administrator, with all necessary supporting documentation, that 

explains how it has met the requirements set forth in paragraph 

(i)(1) of this section. This affirmative defense report shall be 

included in the first periodic compliance report, deviation 

report or excess emission report otherwise required after the 

initial occurrence of the violation of the relevant standard 
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(which may be the end of any applicable averaging period). If 

such compliance report, deviation report or excess emission 

report is due less than 45 days after the initial occurrence of 

the violation, the affirmative defense report may be included in 

the second compliance report, deviation report or excess 

emission report due after the initial occurrence of the 

violation of the relevant standard.

§63.1421 Implementation and enforcement.

(a) This subpart can be implemented and enforced by the 

U.S. EPA, or a delegated authority such as the applicable State, 

local, or Tribal agency. If the U.S. EPA Administrator has 

delegated authority to a State, local, or Tribal agency, then 

that agency, in addition to the U.S. EPA, has the authority to 

implement and enforce this subpart. Contact the applicable U.S. 

EPA Regional Office to find out if this subpart is delegated to 

a State, local, or Tribal agency.

(b) In delegating implementation and enforcement authority 

of this subpart to a State, local, or Tribal agency under 

subpart E of this part, the authorities contained in paragraph 

(c) of this section are retained by the Administrator of U.S. 

EPA and cannot be transferred to the State, local, or Tribal 

agency.
Page 32 of 262

(c) The authorities that cannot be delegated to State, 

local, or Tribal agencies are as specified in paragraphs (c)(1) 

through (4) of this section.

(1) Approval of alternatives to the requirements in 

§§63.1420, 63.1422, 63.1424 through 63.1428, and 63.1432 through 

63.1436. Where these standards reference another subpart, the 

cited provisions will be delegated according to the delegation 

provisions of the referenced subpart. Where these standards 

reference another subpart and modify the requirements, the 

requirements shall be modified as described in this subpart. 

Delegation of the modified requirements will also occur 

according to the delegation provisions of the referenced 

subpart.

(2) Approval of major alternatives to test methods under 

§63.7(e)(2)(ii) and (f), as defined in §63.90, and as required 

in this subpart.

(3) Approval of major alternatives to monitoring under 

§63.8(f), as defined in §63.90, and as required in this subpart.

(4) Approval of major alternatives to recordkeeping and 

reporting under §63.10(f), as defined in §63.90, and as required 

in this subpart.

§63.1422 Compliance dates and relationship of this rule to 

existing applicable rules.

(a) [Reserved]
Page 33 of 262

(b) New affected sources that commence construction or 

reconstruction after September 4, 1997 shall be in compliance 

with this subpart (except §63.1434(c)(3)) upon initial start-up 

or by June 1, 1999, whichever is later. New affected sources 

that commenced construction or reconstruction after September 4, 

1997, but on or before January 9, 2012, shall be in compliance 

with the pressure relief device monitoring requirements of 

§63.1434(c)(3) by [INSERT DATE 3 YEARS AFTER DATE OF PUBLICATION 

IN THE FEDERAL REGISTER]. New affected sources that commence 

construction or reconstruction after January 9, 2012, shall be 

in compliance with the pressure relief device monitoring 

requirements of §63.1434(c)(3) upon initial startup or by 

[INSERT DATE OF PUBLICATION IN THE FEDERAL REGISTER], whichever 

is later.

(c) Existing affected sources shall be in compliance with 

this subpart (except for §63.1434 for which compliance is 

covered by paragraph (d) of this section) no later than June 1, 

2002, as provided in §63.6(c), unless an extension has been 

granted as specified in paragraph (e) of this section.

(d) Except as provided for in paragraphs (d)(1) through 

(56) of this section, existing affected sources shall be in 

compliance with §63.1434 no later than December 1, 1999 unless 

an extension has been granted as specified in paragraph (e) of 

this section.
Page 34 of 262

(1) Compliance with the compressor provisions of §63.164 

shall occur no later than June 1, 2000 for any compressor 

meeting one or more of the criteria in paragraphs (d)(1)(i) 

through (iv) of this section, if the work can be accomplished 

without a process unit shutdown, as defined in §63.161.

(i) The seal system will be replaced.

(ii) A barrier fluid system will be installed.

(iii) A new barrier fluid will be utilized which requires 

changes to the existing barrier fluid system.

(iv) The compressor shall be modified to permit connecting 

the compressor to a closed vent system.

(2) Compliance with the compressor provisions of §63.164 

shall occur no later than December 1, 2000, for any compressor 

meeting all the criteria in paragraphs (d)(2)(i) through (iv) of 

this section.

(i) The compressor meets one or more of the criteria 

specified in paragraphs (d)(1)(i) through (iv) of this section.

(ii) The work can be accomplished without a process unit 

shutdown as defined in §63.161.

(iii) The additional time is necessary, due to the 

unavailability of parts beyond the control of the owner or 

operator.

(iv) The owner or operator submits the request for a 

compliance extension to the appropriate U.S. Environmental 
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Protection Agency Regional Office at the addresses listed in 

§63.13 no later than 45 days before December 1, 1999. The 

request for a compliance extension shall contain the information 

specified in §63.6(i)(6)(i)(A), and (B), and (D). Unless the EPA 

Regional Office objects to the request for a compliance 

extension within 30 days after receipt of the request, the 

request shall be deemed approved.

(3) If compliance with the compressor provisions of §63.164 

cannot reasonably be achieved without a process unit shutdown, 

as defined in §63.161, the owner or operator shall achieve 

compliance no later than June 1, 2001. The owner or operator who 

elects to use this provision shall submit a request for an 

extension of compliance in accordance with the requirements of 

paragraph (d)(2)(iv) of this section.

(4) Compliance with the compressor provisions of §63.164 

shall occur not later than June 1, 2002 for any compressor 

meeting one or more of the criteria in paragraphs (d)(4)(i) 

through (iii) of this section. The owner or operator who elects 

to use these provisions shall submit a request for an extension 

of compliance in accordance with the requirements of paragraph 

(d)(2)(iv) of this section.

(i) Compliance cannot be achieved without replacing the 

compressor.
Page 36 of 262

(ii) Compliance cannot be achieved without recasting the 

distance piece.

(iii) Design modifications are required to connect to a 

closed-vent system.

(5) Compliance with the surge control vessel and bottoms 

receiver provisions of §63.170 shall occur no later than June 1, 

2002.

(6) Compliance with the pressure relief device monitoring 

provisions of §63.1434(c)(3) shall occur no later than [INSERT 

DATE 3 YEARS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER].

(e) Pursuant to section 112(i)(3)(B) of the Act, an owner 

or operator may request an extension allowing the existing 

affected source up to 1 additional year to comply with section 

112(d) standards. For purposes of this subpart, a request for an 

extension shall be submitted to the permitting authority as part 

of the operating permit application, or to the Administrator as 

a separate submittal, or as part of the Precompliance Report. 

Requests for extensions shall be submitted no later than 120 

days prior to the compliance dates specified in paragraphs (b) 

through (d) of this section, or as specified elsewhere in this 

subpart. The dates specified in §63.6(i) for submittal of 

requests for extensions shall not apply to this subpart.

(1) A request for an extension of compliance shall include 

the data described in §63.6(i)(6)(i)(A), and (B), and (D).
Page 37 of 262

(2) The requirements in §63.6(i)(8) through (14) shall 

govern the review and approval of requests for extensions of 

compliance with this subpart.

(3) An owner or operator may submit a compliance extension 

request after the date specified in paragraph (e) of this 

section, provided that the need for the compliance extension 

arose after that date, and the need arose due to circumstances 

beyond reasonable control of the owner or operator. This request 

shall include, in addition to the information specified in 

paragraph (e)(1) of this section, a statement of the reasons 

additional time is needed and the date when the owner or 

operator first learned of the problem.

(f) Table 1 of this subpart specifies the requirements in 

40 CFR part 63, subpart A (the General Provisions) that apply 

and those that do not apply to owners and operators of affected 

sources subject to this subpart. For the purposes of this 

subpart, Table 3 of 40 CFR part 63, subpart F is not applicable.

(g) Table 2 of this subpart summarizes the provisions of 40 

CFR part 63, subparts F, G, and H (collectively known as the 

“HON”) that apply and those that do not apply to owners and 

operators of affected sources subject to this subpart.

(h) [Reserved]

(i) After the compliance dates specified in this section, a 

storage vessel that is assigned to an affected source subject to 
Page 38 of 262

this subpart that is also subject to the 40 CFR part 60, subpart 

Kb (Standards of Performance for Volatile Organic Liquid Storage 

Vessels (Including Petroleum Liquid Storage Vessels) for Which 

Construction, Reconstruction, or Modification Commenced after 

July 23, 1984) is required to comply only with the provisions of 

this subpart. After the compliance dates specified in this 

section, that storage vessel shall no longer be subject to 40 

CFR part 60, subpart Kb.

(j) After the compliance dates specified in this subpart, 

if any combustion device, recovery device or recapture device 

subject to this subpart is also subject to monitoring, 

recordkeeping, and reporting requirements for hazardous waste, 

disposal, and treatment facilities in 40 CFR part 264, subpart 

AA (Air Emission Standards for Process Vents) or subpart CC (Air 

Emission Standards for Tanks, Surface Impoundment, and 

Containers), the owner or operator may comply with either 

paragraph (j)(1) or (2) of this section. If, after the 

compliance dates specified in this subpart, any combustion 

device, recovery device, or recapture device subject to this 

subpart is subject to monitoring and recordkeeping requirements 

hazardous waste treatment, storage, and disposal facilities in 

40 CFR part 265, subpart AA (Air Emission Standards for Process 

Vents) or subpart CC (Air Emission Standards for Tanks, Surface 

Impoundments, and Containers), the owner or operator may comply 
Page 39 of 262

with either paragraph (j)(1) or (3) of this section. If the 

owner or operator elects to comply with either paragraph (j)(2) 

or (3) of this section, the owner or operator shall notify the 

Administrator of this choice in the Notification of Compliance 

Status required by §63.1439(e)(5).

(1) The owner or operator shall comply with the monitoring, 

recordkeeping and reporting requirements of this subpart.

(2) The owner or operator shall comply with the monitoring, 

recordkeeping and reporting requirements in 40 CFR part 264, 

with the following exception. All excursions, as defined in 

§63.1438(f), shall be reported in the periodic report. 

Compliance with this paragraph shall constitute compliance with 

the monitoring, recordkeeping and reporting requirements of this 

subpart.

(3) The owner or operator shall comply with the monitoring 

and recordkeeping requirements of 40 CFR part 265, subpart AA or 

subpart CC, and the periodic reporting requirements under 40 CFR 

part 264, subpart AA or subpart CC, that would apply to the 

device if the facility had final-permitted status, with the 

following exception. All excursions, as defined in §63.1438(f), 

shall be reported in the periodic report. Compliance with this 

paragraph shall constitute compliance with the monitoring, 

recordkeeping and reporting requirements of this subpart.
Page 40 of 262

(k) Paragraphs (k)(1) and (2) of this section address 

instances in which requirements from other regulations overlap 

for the same heat exchange system(s) or waste management unit(s) 

that are subject to this subpart.

(1) After the applicable compliance date specified in this 

subpart, if a heat exchange system subject to this subpart is 

also subject to a standard identified in paragraph (k)(1)(i) or 

(ii) of this section, compliance with the applicable provisions 

of the standard identified in paragraph (k)(1)(i) or (ii) shall 

constitute compliance with the applicable provisions of this 

subpart with respect to that heat exchange system.

(i) 40 CFR part 63, subpart F.

(ii) A subpart of this part which requires compliance with 

the HON heat exchange system requirements in §63.104 (e.g., 40 

CFR part 63, subpart JJJ or U).

(2) After the applicable compliance date specified in this 

subpart, if any waste management unit subject to this subpart is 

also subject to a standard identified in paragraph (k)(2)(i) or 

(ii) of this section, compliance with the applicable provisions 

of the standard identified in paragraph (k)(2)(i) or (ii) shall 

constitute compliance with the applicable provisions of this 

subpart with respect to that waste management unit.

(i) 40 CFR part 63, subpart G.
Page 41 of 262

(ii) A subpart of this part which requires compliance with 

the HON process wastewater provisions in §§63.132 through 63.147 

(e.g., subpart JJJ or U).

(l) All terms in this subpart that define a period of time 

for completion of required tasks (e.g., monthly, quarterly, 

annual), unless specified otherwise in the section or subsection 

that imposes the requirement, refer to the standard calendar 

periods, unless altered by mutual agreement between the owner or 

operator and the Administrator in accordance with paragraph 

(l)(1) of this section.

(1) Notwithstanding time periods specified in this subpart 

for completion of required tasks, such time periods may be 

changed by mutual agreement between the owner or operator and 

the Administrator, as specified in the General Provisions in 40 

CFR part 63, subpart A (e.g., a period could begin on the 

compliance date or another date, rather than on the first day of 

the standard calendar period). For each time period that is 

changed by agreement, the revised period shall remain in effect 

until it is changed. A new request is not necessary for each 

recurring period.

(2) Where the period specified for compliance is a standard 

calendar period, if the initial compliance date occurs after the 

beginning of the period, compliance shall be required according 
Page 42 of 262

to the schedule specified in paragraphs (l)(2)(i) or (ii) of 

this section, as appropriate.

(i) Compliance shall be required before the end of the 

standard calendar period within which the compliance deadline 

occurs, if there remains at least 2 weeks for tasks that shall 

be performed monthly, at least 1 month for tasks that shall be 

performed each quarter, or at least 3 months for tasks that 

shall be performed annually; or

(ii) In all other cases, compliance shall be required 

before the end of the first full standard calendar period after 

the period within which the initial compliance deadline occurs.

(3) In all instances where a provision of this subpart 

requires completion of a task during each of multiple successive 

periods, an owner or operator may perform the required task at 

any time during the specified period, provided that the task is 

conducted at a reasonable interval after completion of the task 

during the previous period.

§63.1423 Definitions.

(a) The following terms used in this subpart shall have the 

meaning given them in subparts A (§63.2), F (§63.101), G 

(§63.111), and H (§63.161) as specified after each term:

Act (subpart A)

Administrator (subpart A)

Automated monitoring and recording system (subpart G)
Page 43 of 262

Boiler (subpart G)

Bottoms receiver (subpart H)

By-product (subpart F)

Car-seal (subpart G)

Closed-vent system (subpart G)

Combustion device (subpart G)

Commenced (subpart A)

Compliance date (subpart A)

Continuous monitoring system (subpart A)

Emission standard (subpart A)

EPA (subpart A)

Equipment (subpart H)

Flow indicator (subpart G)

Fuel gas (subpart F)

Fuel gas system (subpart F)

Hard-piping (subpart G)

Heat exchange system (subpart F)

Impurity (subpart F)

Incinerator (subpart G)

Major source (subpart A)

Malfunction (subpart A)

Oil-water separator or organic-water separator (subpart G)

Open-ended valve or line (subpart H)

Operating permit (subpart F)
Page 44 of 262

Organic monitoring device (subpart G)

Owner or operator (subpart A)

Performance evaluation (subpart A)

Performance test (subpart A)

Permitting authority (subpart A)

Plant site (subpart F)

Potential to emit (subpart A)

Pressure release (subpart H)

Pressure relief device or valve (subpart H)

Primary fuel (subpart G)

Process heater (subpart G)

Process unit shutdown (subpart H)

Reactor (subpart G)

Recapture device (subpart G)

Relief valve (subpart G)

Research and development facility (subpart F)

Responsible official (subpart A)

Run (subpart A)

Secondary fuel (subpart G)

Sensor (subpart H)

Specific gravity monitoring device (subpart G)

Start-up, shutdown, and malfunction plan (subpart F)

State (subpart A)

Surge control vessel (subpart H)
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Temperature monitoring device (subpart G)

Test method (subpart A)

Total resource effectiveness index value (subpart G)

Treatment process (subpart G)

Visible emission (subpart A)

(b) All other terms used in this subpart shall have the 

meaning given them in this section.

Affirmative defense means, in the context of an enforcement 

proceeding, a response or defense put forward by a defendant, 

regarding which the defendant has the burden of proof, and the 

merits of which are independently and objectively evaluated in a 

judicial or administrative proceeding.

Annual average concentration, as used in conjunction with 

the wastewater provisions, means the flow-weighted annual 

average concentration and is determined by the procedures in 

§63.144(b), except as provided in §63.1433(a)(2).

Annual average flow rate, as used in conjunction with the 

wastewater provisions, is determined by the procedures in 

§63.144(c).

Batch cycle means the step or steps, from start to finish, 

that occur in a batch unit operation.

Batch unit operation means a unit operation involving 

intermittent or discontinuous feed into equipment, and, in 

general, involves the emptying of equipment after the batch 
Page 46 of 262

cycle ceases and prior to beginning a new batch cycle. Mass, 

temperature, concentration and other properties of the process 

may vary with time. Addition of raw material and withdrawal of 

product do not simultaneously occur in a batch unit operation.

Catalyst extraction means the removal of the catalyst using 

either solvent or physical extraction method.

Construction means the on-site fabrication, erection, or 

installation of an affected source. Construction also means the 

on-site fabrication, erection, or installation of a process unit 

or a combination of process units which subsequently becomes an 

affected source or part of an affected source due to a change in 

primary product.

Continuous record means documentation, either in hard copy 

or computer readable form, of data values measured at least once 

during approximately equal intervals of 15 minutes and recorded 

at the frequency specified in §63.1439(d).

Continuous recorder is defined in §63.111, except that when 

the definition in §63.111 reads “or records 15-minute or more 

frequent block average values,” the phrase “or records 1-hour or 

more frequent block average values” shall apply for purposes of 

this subpart.

Continuous unit operation means a unit operation where the 

inputs and outputs flow continuously. Continuous unit operations 

typically approach steady-state conditions. Continuous unit 
Page 47 of 262

operations typically involve the simultaneous addition of raw 

material and withdrawal of the product.

Control technique means any equipment or process control 

used for capturing, recovering, or oxidizing organic hazardous 

air pollutant vapors. Such equipment includes, but is not 

limited to, absorbers, adsorbers, boilers, condensers, flares, 

incinerators, process heaters, and scrubbers, or any combination 

thereof. Process control includes extended cookout (as defined 

in this section). Condensers operating as reflux condensers that 

are necessary for processing, such as liquid level control, 

temperature control, or distillation operation, shall be 

considered inherently part of the process and will not be 

considered control techniques.

Emission point means an individual process vent, storage 

vessel, wastewater stream, or equipment leak.

Epoxide means a chemical compound consisting of a threemembered cyclic ether. Only emissions of epoxides listed in 

Table 4 of this subpart (i.e., ethylene oxide, propylene oxide, 

and epichlorohydrin) are regulated by the provisions of this 

subpart.

Equipment leak means emissions of organic HAP from a 

connector, pump, compressor, agitator, pressure relief device, 

sampling connection system, open-ended valve or line, valve, 
Page 48 of 262

surge control vessel, bottoms receiver, or instrumentation 

system in organic HAP service.

Extended Cookout (ECO) means a control technique that 

reduces the amount of unreacted ethylene oxide (EO) and/or 

propylene oxide (PO) (epoxides) in the reactor. This is 

accomplished by allowing the product to react for a longer time 

period, thereby having less unreacted epoxides and reducing 

epoxides emissions that may have otherwise occurred.

Flexible operation unit means a process unit that 

manufactures different chemical products by periodically 

alternating raw materials fed to the process unit or operating 

conditions at the process unit. These units are also referred to 

as campaign plants or blocked operations.

Group 1 combination of batch process vents means a 

collection of process vents in a PMPU from batch unit operations 

that are associated with the use of a nonepoxide organic HAP to 

make or modify the product that meet all of the following 

conditions:

(1) Has annual nonepoxide organic HAP emissions, determined 

in accordance with §63.1428(b), of 11,800 kg/yr or greater, and

(2) Has a cutoff flow rate, determined in accordance with 

§63.1428(e), that is greater than or equal to the annual average 

flow rate, determined in accordance with §63.1428(d).
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Group 2 combination of batch process vents means a 

collection of process vents in a PMPU from batch unit operations 

that are associated with the use of a nonepoxide organic HAP to 

make or modify the product that is not classified as a Group 1 

combination of batch process vents.

Group 1 continuous process vent means a process vent from a 

continuous unit operation that is associated with the use of a 

nonepoxide organic HAP to make or modify the product that meets 

all of the following conditions:

(1) Has a flow rate greater than or equal to 0.005 standard 

cubic meters per minute,

(2) Has a total organic HAP concentration greater than or 

equal to 50 parts per million by volume, and

(3) Has a total resource effectiveness index value, 

calculated in accordance with §63.1428(h)(1), less than or equal 

to 1.0.

Group 2 continuous process vent means a process vent from a 

continuous unit operation that is associated with the use of a 

nonepoxide organic HAP to make or modify the product that is not 

classified as a Group 1 continuous process vent.

Group 1 storage vessel means a storage vessel that meets 

the applicability criteria specified in Table 3 of this subpart.

Group 2 storage vessel means a storage vessel that does not 

fall within the definition of a Group 1 storage vessel.
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Group 1 wastewater stream means a process wastewater stream 

at an existing or new affected source that meets the criteria 

for Group 1 status in §63.132(c), with the exceptions listed in 

§63.1433(a)(2) for the purposes of this subpart (i.e., for 

organic HAP listed on Table 4 of this subpart only).

Group 2 wastewater stream means any process wastewater 

stream at an existing affected source or new affected source 

that does not meet the definition (in this section) of a Group 1 

wastewater stream.

In organic hazardous air pollutant service or in organic 

HAP service means that a piece of equipment either contains or 

contacts a fluid (liquid or gas) that is at least 5 percent by 

weight of total organic HAP (as defined in this section), as 

determined according to the provisions of §63.180(d). The 

provisions of §63.180(d) also specify how to determine that a 

piece of equipment is not in organic HAP service.

Initial start-up means the first time a new or 

reconstructed affected source begins production, or, for 

equipment added or changed as described in §63.1420(g), the 

first time the equipment is put into operation to produce a 

polyether polyol. Initial start-up does not include operation 

solely for testing equipment. Initial start-up does not include 

subsequent start-ups of an affected source or portion thereof 

following malfunctions or shutdowns or following changes in 
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product for flexible operation units. Further, for purposes of 

§63.1422, initial start-up does not include subsequent start-ups 

of affected sources or portions thereof following malfunctions 

or process unit shutdowns.

Maintenance wastewater is defined in §63.101, except that 

the term “polyether polyol manufacturing process unit” shall 

apply whenever the term “chemical manufacturing process unit” is 

used. Further, the generation of wastewater from the routine 

rinsing or washing of equipment in batch operation between 

batches is not maintenance wastewater, but is considered to be 

process wastewater, for the purposes of this subpart.

Make or modify the product means to produce the polyether 

polyol by polymerization of epoxides or other cyclic ethers with 

compounds having one or more reactive hydrogens, and to 

incorporate additives (e.g., preservatives, antioxidants, or 

diluents) in order to maintain the quality of the finished 

products before shipping. Making and modifying the product for 

this regulation does not include grafting, polymerizing the 

polyol, or reacting it with compounds other than EO or PO.

Maximum true vapor pressure is defined in §63.111, except 

that the terms “transfer” and “transferred” shall not apply for 

the purposes of this subpart.
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New process unit means a process unit for which the 

construction or reconstruction commenced after September 4, 

1997.

On-site or on site means, with respect to records required 

to be maintained by this subpart or required by another subpart 

referenced by this subpart, a location within the plant site 

where the affected source is located. On-site storage of records 

includes, but is not limited to, a location at the affected 

source or PMPU to which the records pertain or a location 

elsewhere at the plant site where the affected source is 

located.

Operating day refers to the 24-hour period defined by the 

owner or operator in the Notification of Compliance Status 

required by §63.1439(e)(5). That 24-hour period may be from 

midnight to midnight or another 24-hour period. The operating 

day is the 24-hour period for which daily average monitoring 

values are determined.

Organic hazardous air pollutant(s) (organic HAP) means one 

or more of the chemicals listed in Table 4 of this subpart, or 

any other chemical which:

(1) Is knowingly produced or introduced into the 

manufacturing process other than as an impurity; and

(2) Is listed in Table 2 of 40 CFR part 63, subpart F in 

the HON.
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Polyether polyol means a compound formed through the 

polymerization of EO or PO or other cyclic ethers with compounds 

having one or more reactive hydrogens (i.e., a hydrogen atom 

bonded to nitrogen, oxygen, phosphorus, sulfur, etc.) to form 

polyethers (i.e., compounds with two or more ether bonds). This 

definition of polyether polyol excludes cellulose ethers (such 

as methyl cellulose, carboxymethyl cellulose, hydroxyethyl 

cellulose, hydroxy ethyl cellulose, and hydroxypropyl methyl 

cellulose) and materials regulated under 40 CFR part 63, 

subparts F, G, and H (the HON), such as glycols and glycol 

ethers.

Polyether polyol manufacturing process unit (PMPU) means a 

process unit that manufactures a polyether polyol as its primary 

product, or a process unit designated as a polyether polyol 

manufacturing unit in accordance with §63.1420(e)(2). A 

polyether polyol manufacturing process unit consists of more 

than one unit operation. This collection of equipment includes 

purification systems, reactors and their associated product 

separators and recovery devices, distillation units and their 

associated distillate receivers and recovery devices, other 

associated unit operations, storage vessels, surge control 

vessels, bottoms receivers, product transfer racks, connected 

ducts and piping, combustion, recovery, or recapture devices or 

systems, and the equipment (i.e., all pumps, compressors, 
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agitators, pressure relief devices, sampling connection systems, 

open-ended valves or lines, valves, connectors, and 

instrumentation systems that are associated with the PMPU) that 

are subject to the equipment leak provisions as specified in 

§63.1434.

Pressure decay curve is the graph of the reactor pressure 

versus time from the point when epoxide feed is stopped until 

the reactor pressure is constant, indicating that most of the 

epoxide has reacted out of the vapor and liquid phases. This 

curve shall be determined with no leaks or vents from the 

reactor.

Primary product is defined in and determined by the 

procedures specified in §63.1420(e).

Process unit means a collection of equipment assembled and 

connected by pipes or ducts to process raw materials and to 

manufacture a product.

Process vent means a point of emission from a unit 

operation having a gaseous stream that is discharged to the 

atmosphere either directly or after passing through one or more 

combustion, recovery, or recapture devices. A process vent from 

a continuous unit operation is a gaseous emission stream 

containing more than 0.005 weight-percent total organic HAP. A 

process vent from a batch unit operation is a gaseous emission 

stream containing more than 225 kilograms per year (500 pounds 
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per year) of organic HAP emissions. Unit operations that may 

have process vents are condensers, distillation units, reactors, 

or other unit operations within the PMPU. Process vents exclude 

pressure relief device valve discharges, gaseous streams routed 

to a fuel gas system(s), and leaks from equipment regulated 

under §63.1434. A gaseous emission stream is no longer 

considered to be a process vent after the stream has been 

controlled and monitored in accordance with the applicable 

provisions of this subpart.

Process wastewater means wastewater which, during 

manufacturing or processing, comes into direct contact with or 

results from the production or use of any raw material, 

intermediate product, finished product, by-product, or waste 

product. Examples are product tank drawdown or feed tank 

drawdown; water formed during a chemical reaction or used as a 

reactant; water used to wash impurities from organic products or 

reactants; equipment washes between batches in a batch process; 

water used to cool or quench organic vapor streams through 

direct contact; and condensed steam from jet ejector systems 

pulling vacuum on vessels containing organics.

Product means a compound or material which is manufactured 

by a process unit. By-products, isolated intermediates, 

impurities, wastes, and trace contaminants are not considered 

products.
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Product class means a group of polyether polyols with a 

similar pressure decay curve (or faster pressure decay curves) 

that are manufactured within a given set of operating conditions 

representing the decline in pressure versus time. All products 

within a product class shall have an essentially similar 

pressure decay curve, and operate within a given set of 

operating conditions. These operating conditions are: a minimum 

reaction temperature; the number of -OH groups in the polyol; a 

minimum catalyst concentration; the type of catalyst (e.g., 

self-catalyzed, base catalyst, or acid catalyst); the epoxide 

ratio, or a range for that ratio; and the reaction conditions of 

the system (e.g., the size of the reactor, or the size of the 

batch).

Reactor liquid means the compound or material made in the 

reactor, even though the substance may be transferred to another 

vessel. This material may require further modifications before 

becoming a final product, in which case the reactor liquid is 

classified as an “intermediate.” This material may be complete 

at this stage, in which case the reactor liquid is classified as 

a “product.”

Reconstruction means the replacement of components of an 

affected source or of a previously unaffected stationary source 

that becomes an affected source as a result of the replacement, 

to such an extent that:
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(1) The fixed capital cost of the new components exceeds 50 

percent of the fixed capital cost that would be required to 

construct a comparable new source; and

(2) It is technologically and economically feasible for the 

reconstructed source to meet the provisions of this subpart.

Recovery device means an individual unit of equipment 

capable of and normally used for the purpose of recovering 

chemicals for fuel value (i.e., net positive heating value), 

use, reuse, or for sale for fuel value, use, or reuse. Examples 

of equipment that may be recovery devices include absorbers, 

carbon adsorbers, condensers (except reflux condensers), oilwater separators or organic-water separators, or organic removal 

devices such as decanters, strippers, or thin film evaporation 

units. For the purposes of the monitoring, recordkeeping, or 

reporting requirements of this subpart, recapture devices are 

considered to be recovery devices.

Residual is defined in §63.111, except that when the 

definition in §63.111 uses the term “Table 9 compounds,” the 

term “organic HAP listed in Table 9 of subpart G” shall apply, 

for the purposes of this subpart.

Shutdown means the cessation of operation of an affected 

source, a PMPU within an affected source, a waste management 

unit or unit operation within an affected source, equipment 

required or used to comply with this subpart, or the emptying or 
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degassing of a storage vessel. The purposes for a shutdown may 

include, but are not limited to, periodic maintenance, 

replacement of equipment, or equipment repairs. Shutdown does 

not include the normal periods between batch cycles. For 

continuous unit operations, shutdown includes transitional 

conditions due to changes in product for flexible operation 

units. For batch unit operations, shutdown does not include 

transitional conditions due to changes in product for flexible 

operation units. For purposes of the wastewater provisions, 

shutdown does not include the routine rinsing or washing of 

equipment between batch cycles.

Start-up means the setting into operation of an affected 

source, a PMPU within the affected source, a waste management 

unit or unit operation within an affected source, equipment 

required or used to comply with this subpart, or a storage 

vessel after emptying and degassing. For all processes, start-up 

includes initial start-up and operation solely for testing 

equipment. Start-up does not include the recharging of batch 

unit operations. For continuous unit operations, start-up 

includes transitional conditions due to changes in product for 

flexible operation units. For batch unit operations, start-up 

does not include transitional conditions due to changes in 

product for flexible operation units.
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Steady-state conditions means that all variables 

(temperatures, pressures, volumes, flow rates, etc.) in a 

process do not vary significantly with time; minor fluctuations 

about constant mean values may occur.

Storage vessel means a tank or other vessel that is used to 

store liquids that contain one or more organic HAP. Storage 

vessels do not include:

(1) Vessels permanently attached to motor vehicles such as 

trucks, railcars, barges, or ships;

(2) Pressure vessels designed to operate in excess of 204.9 

kilopascals and without emissions to the atmosphere;

(3) Vessels with capacities smaller than 38 cubic meters;

(4) Vessels and equipment storing and/or handling material 

that contains no organic HAP, or organic HAP as impurities only;

(5) Surge control vessels and bottoms receiver tanks;

(6) Wastewater storage tanks; and

(7) Storage vessels assigned to another process unit 

regulated under another subpart of part 63.

Total organic compounds (TOC) are those compounds, 

excluding methane and ethane, measured according to the 

procedures of Method 18 or Method 25A of 40 CFR part 60, 

appendix A.

Unit operation means one or more pieces of process 

equipment used to make a single change to the physical or 
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chemical characteristics of one or more process streams. Unit 

operations include, but are not limited to, reactors, 

distillation units, extraction columns, absorbers, decanters, 

condensers, and filtration equipment.

Vent stream, as used in reference to process vents, means 

the emissions from a process vent.

Waste management unit is defined in §63.111, except that 

when the definition in §63.111 uses the term “chemical 

manufacturing process unit,” the term “PMPU” shall apply for the 

purposes of this subpart.

Wastewater means water that:

(1) Contains either

(i) An annual average concentration of organic HAP listed 

in Table 4 of this subpart of at least 5 parts per million by 

weight and has an annual average flow rate of 0.02 liter per 

minute or greater, or

(ii) An annual average concentration of organic HAP listed 

on Table 4 of this subpart of at least 10,000 parts per million 

by weight at any flow rate; and that

(2) Is discarded from a PMPU that is part of an affected 

source. Wastewater is process wastewater or maintenance 

wastewater.

§63.1424 Emission standards.
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(a) Except as provided under paragraph (b) of this section, 

the owner or operator of an existing or new affected source 

shall comply with the provisions in:

(1) Sections 63.1425 through 63.1430 for process vents;

(2) Section 63.1432 for storage vessels;

(3) Section 63.1433 for wastewater;

(4) Section 63.1434 for equipment leaks;

(5) Section 63.1435 for heat exchangers;

(6) Section 63.1437 for additional test methods and 

procedures;

(7) Section 63.1438 for monitoring levels and excursions; 

and

(8) Section 63.1439 for general reporting and recordkeeping 

requirements.

(b) When emissions of different kinds (i.e., emissions from 

process vents subject to §§63.1425 through 63.1430, storage 

vessels subject to §63.1432, process wastewater, and/or inprocess equipment subject to §63.149) are combined, and at least 

one of the emission streams would require control according to 

the applicable provision in the absence of combination with 

other emission streams, the owner or operator shall comply with 

the requirements of either paragraph (b)(1) or (2) of this 

section.
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(1) Comply with the applicable requirements of this subpart 

for each kind of emission in the stream as specified in 

paragraphs (a)(1) through (5) of this section; or

(2) Comply with the most stringent set of requirements that 

applies to any individual emission stream that is included in 

the combined stream, where either that emission stream would be 

classified as requiring control in the absence of combination 

with other emission streams, or the owner chooses to consider 

that emission stream to require control for the purposes of this 

paragraph.

§63.1425 Process vent control requirements.

(a) Applicability of process vent control requirements. For 

each process vent at an affected source, the owner or operator 

shall comply with the provisions of this section. Owners and 

operators of all affected sources using epoxides in the 

production of polyether polyols are subject to the requirements 

of paragraph (b) of this section. Owners or operators are 

subject to the requirements of paragraph (c) of this section 

only if epoxides are used in the production of polyether polyols 

and nonepoxide organic HAP are used to make or modify the 

product. Similarly, owners or operators are subject to the 

requirements of paragraph (d) of this section only if epoxides 

are used in the production of polyether polyols and organic HAP 

are used in catalyst extraction. The owner or operator of an 
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affected source where polyether polyol products are produced 

using tetrahydrofuran shall comply with paragraph (f) of this 

section.

(b) Requirements for epoxide emissions. The owner or 

operator of an affected source where polyether polyol products 

are produced using epoxides shall reduce epoxide emissions from 

process vents from batch unit operations and continuous unit 

operations within each PMPU in accordance with either paragraph 

(b)(1) or (2) of this section.

(1) For new affected sources, the owner or operator shall 

comply with paragraph (b)(1)(i), (ii), or (iii) this section. 

The owner or operator also has the option of complying with a 

combination of paragraphs (b)(1)(i) and (ii) of this section. If 

the owner or operator chooses to comply with a combination of 

paragraphs (b)(1)(i) and (ii) of this section, each process vent 

not controlled in accordance with paragraph (b)(1)(ii) of this 

section shall be part of the group of applicable process vents 

that shall then comply with paragraph (b)(1)(i) of this section.

(i) Reduce the total epoxide emissions from the group of 

applicable process vents by an aggregated 99.9 percent;

(ii) Maintain an outlet concentration of total epoxides or 

TOC after each combustion, recapture, or recovery device of 20 

ppmv or less; or
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(iii) Maintain an emission factor of no greater than 4.43 × 

10−3 kilogram epoxide emissions per megagram of product (4.43 × 

10−3 pounds epoxide emissions per 1,000 pounds of product) for 

all process vents in the PMPU.

(2) For existing affected sources, the owner or operator 

shall comply with either paragraph (b)(2)(i), (ii), (iii), or 

(iv) of this section. The owner or operator also has the option 

of complying with a combination of paragraphs (b)(2)(ii) and 

(iii) of this section. If the owner or operator chooses to 

comply with a combination of paragraphs (b)(2)(ii) and (iii) of 

this section, each process vent that is not controlled in 

accordance with paragraph (b)(2)(iii) of this section shall be 

part of the group of applicable process vents that shall then 

comply with paragraph (b)(2)(ii) of this section. The owner or 

operator also has the option of complying with a combination of 

paragraphs (b)(2)(i) and (iii) of this section.

(i) Reduce the total epoxide emissions from each process 

vent using a flare;

(ii) Reduce the total epoxide emissions from the group of 

applicable process vents by an aggregated 98 percent;

(iii) Maintain an outlet concentration of total epoxides or 

TOC after each combustion, recapture or recovery devices of 20 

ppmv or less; or
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(iv) Maintain an emission factor of no greater than 1.69 × 

10−2 kilogram epoxide emissions per megagram of product (1.69 × 

10−2 pounds epoxide emissions per 1,000 pounds of product) for 

all process vents in the PMPU.

(c) Requirements for nonepoxide organic HAP emissions from 

making or modifying the product. The owner or operator of a new 

or existing source where polyether polyols are produced using 

epoxides, and where nonepoxide organic HAP are used to make or 

modify the product, shall comply with this paragraph. For each 

process vent from a continuous unit operation that is associated 

with the use of a nonepoxide organic HAP to make or modify the 

product, the owner or operator shall determine if the process 

vent is a Group 1 continuous process vent, as defined in 

§63.1423. For the combination of process vents from batch unit 

operations that are associated with the use of a nonepoxide 

organic HAP to make or modify the product, the owner or operator 

shall determine if the combination of process vents is a Group 1 

combination of batch process vents, as defined in §63.1423.

(1) Requirements for Group 1 combinations of batch process 

vents. For each Group 1 combination of batch process vents, as 

defined in §63.1423, the owner or operator shall comply with 

either paragraph (c)(1)(i) or (ii) of this section.

(i) Reduce nonepoxide organic HAP emissions using a flare.
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(ii) Reduce nonepoxide organic HAP emissions by 90 percent 

using a combustion, recovery, or recapture device.

(2) Requirements for Group 2 combinations of batch process 

vents. For each Group 2 combination of batch process vents, as 

defined in §63.1423, the owner or operator reassess the group 

status when process changes occur, in accordance with the 

provisions of §63.1428(g). No control requirements apply to 

these process vents.

(3) Requirements for Group 1 continuous process vents. For 

each Group 1 continuous process vent, as defined in §63.1423, 

the owner or operator shall comply with either paragraph 

(c)(3)(i) or (ii) of this section.

(i) Reduce nonepoxide organic HAP emissions using a flare.

(ii) Reduce nonepoxide organic HAP emissions by 98 percent 

using a combustion, recovery, or recapture device.

(4) Requirements for Group 2 continuous process vents. For 

each Group 2 continuous process vent, as defined in §63.1423, 

the owner or operator shall comply with either paragraph 

(c)(4)(i) or (ii) of this section.

(i) If the TRE for the process vent is greater than 1.0 but 

less than 4.0, the owner or operator shall comply with the 

monitoring provisions in §63.1429, the recordkeeping provisions 

in §63.1430(d), and recalculate the TRE index value when process 
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changes occur, in accordance with the provisions in 

§63.1428(h)(2).

(ii) If the TRE for the process vent is greater than 4.0, 

the owner or operator shall recalculate the TRE index value when 

process changes occur, in accordance with the provisions in 

§63.1428(h)(2).

(d) Requirements for nonepoxide organic HAP emissions from 

catalyst extraction. The owner or operator of a new or existing 

affected source where polyether polyol products are produced 

using epoxide compounds shall comply with either paragraph 

(d)(1) or (2) of this section. A PMPU that does not use any 

nonepoxide organic HAP in catalyst extraction is exempt from the 

requirements of this paragraph.

(1) Reduce emissions of nonepoxide organic HAP from all 

process vents associated with catalyst extraction using a flare; 

or

(2) Reduce emissions of nonepoxide organic HAP from the sum 

total of all process vents associated with catalyst extraction 

by an aggregated 90 percent for each PMPU.

(e) [Reserved]

(f) Requirements for process vents at PMPUs that produce 

polyether polyol products using tetrahydrofuran. For each 

process vent in a PMPU that uses tetrahydrofuran (THF) to 

produce one or more polyether polyol products that is, or is 
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part of, an affected source, the owner or operator shall comply 

with the HON process vent requirements in §§63.113 through 

63.118, except as provided for in paragraphs (f)(1) through (10) 

of this section.

(1) When December 31, 1992 is referred to in the HON 

process vent requirements in §63.113, it shall be replaced with 

September 4, 1997, for the purposes of this subpart.

(2) When §63.151(f), alternative monitoring parameters, and 

§63.152(e), submission of an operating permit application, are 

referred to in §§63.114(c) and 63.117(e), §63.1439(f), 

alternative monitoring parameters, and §63.1439(e)(8), 

submission of an operating permit application, respectively, 

shall apply for the purposes of this subpart.

(3) When the Notification of Compliance Status requirements 

contained in §63.152(b) are referred to in §§63.114, 63.117, and 

63.118, the Notification of Compliance Status requirements 

contained in §63.1439(e)(5) shall apply for the purposes of this 

subpart.

(4) When the Periodic Report requirements contained in 

§63.152(c) are referred to in §§63.117 and 63.118, the Periodic 

Report requirements contained in §63.1439(e)(6) shall apply for 

the purposes of this subpart.

(5) When the definition of excursion in 

§63.152(c)(2)(ii)(A) is referred to in §63.118(f)(2), the 
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definition of excursion in §63.1438(f) shall apply for the 

purposes of this subpart.

(6) When §63.114(e) specifies that an owner or operator 

shall submit the information required in §63.152(b) in order to 

establish the parameter monitoring range, the owner or operator 

shall comply with the provisions of §63.1438 for establishing 

the parameter monitoring level and shall comply with 

§63.1439(e)(5)(ii) or §63.1439(e)(8) for the purposes of 

reporting information related to the establishment of the 

parameter monitoring level, for the purposes of this subpart. 

Further, the term “level” shall apply whenever the term “range” 

is used in §§63.114, 63.117, and 63.118.

(7) When reports of process changes are required under 

§63.118(g), (h), (i), or (j), paragraphs (f)(7)(i) through (iv) 

of this section shall apply for the purposes of this subpart.

(i) For the purposes of this subpart, whenever a process 

change, as defined in §63.115(e), is made that causes a Group 2 

process vent to become a Group 1 process vent, the owner or 

operator shall submit a report within 180 days after the process 

change is made or the information regarding the process change 

is known to the owner or operator. This report may be included 

in the next Periodic Report. A description of the process change 

shall be included in this report.
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(ii) Whenever a process change, as defined in §63.115(e), 

is made that causes a Group 2 process vent with a TRE greater 

than 4.0 to become a Group 2 process vent with a TRE less than 

4.0, the owner or operator shall submit a report within 180 days 

after the process change is made or the information regarding 

the process change is known to the owner or operator, unless the 

flow rate is less than 0.005 standard cubic meters per minute. 

This report may be included in the next Periodic Report. A 

description of the process change shall be included in this 

report.

(iii) Whenever a process change, as defined in §63.115(e), 

is made that causes a Group 2 process vent with a flow rate less 

than 0.005 standard cubic meter per minute (scmm) to become a 

Group 2 process vent with a flow rate of 0.005 scmm or greater 

and a TRE index value less than or equal to 4.0, the owner or 

operator shall submit a report within 180 days after the process 

change is made or the information regarding the process change 

is known to the owner or operator, unless the organic HAP 

concentration is less than 50 ppmv. This report may be included 

in the next Periodic Report. A description of the process change 

shall be submitted with the report.

(iv) Whenever a process change, as defined in §63.115(e), 

is made that causes a Group 2 process vent with an organic HAP 

concentration less than 50 parts per million by volume (ppmv) to 
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become a Group 2 process vent with an organic HAP concentration 

of 50 ppmv or greater and a TRE index value less than or equal 

to 4.0, the owner or operator shall submit a report within 180 

days after the process change is made or the information 

regarding the process change is known to the owner or operator, 

unless the flow rate is less than 0.005 standard cubic meters 

per minute. This report may be included in the next Periodic 

Report. A description of the process change shall be submitted 

with this report.

(8) When §63.118 refers to §63.152(f), the recordkeeping 

requirements in §63.1439(d) shall apply for the purposes of this 

subpart.

(9) When §§63.115 and 63.116 refer to Table 2 of 40 CFR 

part 63, subpart F, the owner or operator shall only consider 

organic HAP as defined in this subpart.

(10) When the provisions of §63.116(c)(3) and (4) specify 

that Method 18, 40 CFR part 60, appendix A shall be used, Method 

18 or Method 25A, 40 CFR part 60, appendix A may be used for the 

purposes of this subpart. The use of Method 25A, 40 CFR part 60, 

appendix A shall comply with paragraphs (f)(10)(i) and (ii) of 

this section.

(i) The organic HAP used as the calibration gas for Method 

25A, 40 CFR part 60, appendix A shall be the single organic HAP 

representing the largest percent by volume of the emissions.
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(ii) The use of Method 25A, 40 CFR part 60, appendix A is 

acceptable if the response from the high-level calibration gas 

is at least 20 times the standard deviation of the response from 

the zero calibration gas when the instrument is zeroed on the 

most sensitive scale.

§63.1426 Process vent requirements for determining organic HAP 

concentration, control efficiency, and aggregated organic HAP 

emission reduction for a PMPU.

(a) Use of a flare. When a flare is used to comply with 

§63.1425(b)(1)(i) (in combination with other control 

techniques), (b)(2)(i), (c)(1)(i), (c)(3)(i), or (d)(1), the 

owner or operator shall comply with §63.1437(c), and is not 

required to demonstrate the control efficiency for the flare, if 

the owner or operator chooses to assume a 98 percent control 

efficiency for that flare, as allowed under paragraph (e)(2)(i) 

of this section. In order to use only a flare to comply with 

§63.1425(b)(1)(i), or to use a flare and apply a control 

efficiency greater than 98 percent, an owner or operator shall 

submit a request in accordance with §63.6(g) in either the 

Precompliance Report described in §63.1439(e)(4), or in a 

supplement to the precompliance report, as described in 

§63.1439(e)(4)(vii).

(b) Exceptions to performance tests. An owner or operator 

is not required to conduct a performance test when a combustion, 
Page 73 of 262

recovery, or recapture device specified in paragraphs (b)(1) 

through (6) of this section is used to comply with §63.1425(b), 

(c), or (d).

(1) A boiler or process heater with a design heat input 

capacity of 44 megawatts or greater.

(2) A boiler or process heater where the process vent 

stream is introduced with the primary fuel or is used as the 

primary fuel.

(3) A combustion, recovery, or recapture device for which a 

performance test was conducted within the preceding 5-year 

period, using the same Methods specified in this section and 

either no deliberate process changes have been made since the 

test, or the owner or operator can demonstrate that the results 

of the performance test, with or without adjustments, reliably 

demonstrate compliance despite process changes. The operating 

parameters reported under the previous performance test shall be 

sufficient to meet the parameter monitoring requirements in this 

subpart.

(4) A boiler or process heater burning hazardous waste for 

which the owner or operator:

(i) Has been issued a final hazardous waste permit under 40 

CFR part 270 and complies with the requirements for hazardous 

waste burned in boilers and industrial furnaces in 40 CFR part 

266, subpart H; or
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(ii) Has certified compliance with the interim status 

requirements for hazardous waste burned in boilers and 

industrial furnaces in of 40 CFR part 266, subpart H.

(5) A hazardous waste incinerator for which the owner or 

operator has been issued a final permit under 40 CFR part 270 

and complies with the requirements for incinerators in 40 CFR 

part 264, subpart O, or has certified compliance with the 

interim status requirements for incinerators in 40 CFR part 265, 

subpart O.

(6) Combustion, recovery or recapture device (except for 

condensers) performance may be determined by using the design 

evaluation described in paragraph (f) of this section, provided 

that the combustion, recovery or recapture device receives less 

than 10 tons per year (9.1 megagrams per year) of uncontrolled 

organic HAP emissions from one or more PMPUs, determined in 

accordance with paragraph (d) of this section. If a combustion, 

recovery or recapture device exempted from testing in accordance 

with this paragraph receives more than 10 tons per year (9.1 

megagrams per year) of uncontrolled organic HAP emissions from 

one or more PMPUs, the owner or operator shall comply with the 

performance test requirements in paragraph (c) of this section 

and shall submit the test report in the next Periodic Report.

(c) Determination of organic HAP concentration and control 

efficiency. Except as provided in paragraphs (a) and (b) of this 
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section, an owner or operator using a combustion, recovery, or 

recapture device to comply with an epoxide or organic HAP 

percent reduction efficiency requirement in §63.1425(b)(1)(i), 

(b)(2)(ii), (c)(1)(ii), (c)(3)(ii), or (d)(2); an epoxide 

concentration limitation in §63.1425(b)(1)(ii) or (b)(2)(ii); or 

an annual epoxide emission limitation in §63.1425(b)(1)(iii) or 

(b)(2)(iv), shall conduct a performance test using the 

applicable procedures in paragraphs (c)(1) through (4) of this 

section. The organic HAP or epoxide concentration and percent 

reduction may be measured as total epoxide, total organic HAP, 

or as TOC minus methane and ethane according to the procedures 

specified. When conducting testing in accordance with this 

section, the owner or operator is only required to measure HAP 

of concern for the specific requirement for which compliance is 

being determined. For instance, to determine compliance with the 

epoxide emission requirement of §63.1425(b), the owner or 

operator is only required to measure epoxide control efficiency 

or outlet concentration.

(1) Sampling site location. The sampling site location 

shall be determined as specified in paragraphs (c)(1)(i) and 

(ii) of this section.

(i) For determination of compliance with a percent 

reduction of total epoxide requirement in §63.1425(b)(1)(i), 

(b)(2)(ii), or a percent reduction of total organic HAP 
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requirement in §63.1425(c)(1)(ii), (c)(3)(ii), or (d)(2), 

sampling sites shall be located at the inlet of the combustion, 

recovery, or recapture device as specified in paragraphs 

(c)(1)(i)(A), (B), and (C) of this section, and at the outlet of 

the combustion, recovery, or recapture device.

(A) For process vents from continuous unit operations, the 

inlet sampling site shall be determined in accordance with 

either paragraph (c)(1)(i)(A)(1) or (2) of this section.

(1) To demonstrate compliance with either the provisions 

for epoxide emissions in §63.1425(b) or the provisions for 

nonepoxide organic HAP emissions from catalyst extraction in 

§63.1425(d), the inlet sampling site shall be located after the 

exit from the continuous unit operation but before any recovery 

devices, or

(2) To demonstrate compliance with the requirements for 

nonepoxide organic HAP emissions from the use of nonepoxide 

organic HAP in making or modifying the product in §63.1425(c), 

the inlet sampling site shall be located after all control 

techniques to reduce epoxide emissions and after the final 

nonepoxide organic HAP recovery device.

(B) For process vents from batch unit operations, the inlet 

sampling site shall be determined in accordance with either 

paragraph (c)(1)(i)(B)(1) or (2) of this section.
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(1) To demonstrate compliance with either the provisions 

for epoxide emissions in §63.1425(b) or the provisions for 

nonepoxide organic HAP emissions from catalyst extraction in 

§63.1425(d), the inlet sampling site shall be located after the 

exit from the batch unit operation but before any recovery 

device.

(2) To demonstrate compliance with the requirements for 

nonepoxide organic HAP emissions in making or modifying the 

product in §63.1425(c), the inlet sampling site shall be located 

after all control techniques to reduce epoxide emissions but 

before any nonepoxide organic HAP recovery device.

(C) If a process vent stream is introduced with the 

combustion air or as a secondary fuel into a boiler or process 

heater with a design capacity less than 44 megawatts, selection 

of the location of the inlet sampling sites shall ensure the 

measurement of total organic HAP or TOC (minus methane and 

ethane) concentrations in all process vent streams and primary 

and secondary fuels introduced into the boiler or process 

heater.

(ii) To determine compliance with a parts per million by 

volume total epoxide or TOC limit in §63.1425(b)(1)(ii) or 

(b)(2)(iii), the sampling site shall be located at the outlet of 

the combustion, recovery, or recapture device.

(2) [Reserved]
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(3) Testing conditions and calculation of TOC or total 

organic HAP concentration. (i) Testing conditions shall be as 

specified in paragraphs (c)(3)(i)(A) through (E) of this 

section, as appropriate.

(A) Testing of process vents from continuous unit 

operations shall be conducted at maximum representative 

operating conditions, as described in §63.1437(a)(1). Each test 

shall consist of three l-hour runs. Gas stream volumetric flow 

rates shall be measured at approximately equal intervals of 

about 15 minutes during each 1-hour run. The organic HAP 

concentration (of the HAP of concern) shall be determined from 

samples collected in an integrated sample over the duration of 

each l-hour test run, or from grab samples collected 

simultaneously with the flow rate measurements (at approximately 

equal intervals of about 15 minutes). If an integrated sample is 

collected for laboratory analysis, the sampling rate shall be 

adjusted proportionally to reflect variations in flow rate. For 

gas streams from continuous unit operations, the organic HAP 

concentration or control efficiency used to determine compliance 

shall be the average organic HAP concentration or control 

efficiency of the three test runs.

(B) Testing of process vents from batch unit operations 

shall be conducted at absolute worst-case conditions or 

hypothetical worst-case conditions, as defined in paragraphs 
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(c)(3)(i)(B)(1) through (5) of this section. Worst-case 

conditions are limited to the maximum production allowed in a 

State or Federal permit or regulation and the conditions 

specified in §63.1437(a)(1). Gas stream volumetric flow rates 

shall be measured at 15-minute intervals, or at least once 

during the emission episode. The organic HAP or TOC 

concentration shall be determined from samples collected in an 

integrated sample over the duration of the test, or from grab 

samples collected simultaneously with the flow rate measurements 

(at approximately equal intervals of about 15 minutes). If an 

integrated sample is collected for laboratory analysis, the 

sampling rate shall be adjusted proportionally to reflect 

variations in flow rate.

(1) Absolute worst-case conditions are defined by the 

criteria presented in paragraph (c)(3)(i)(B)(1)(i) or (ii) of 

this section if the maximum load is the most challenging 

condition for the control device. Otherwise, absolute worst-case 

conditions are defined by the conditions in paragraph 

(c)(3)(i)(B)(1)(iii) of this section.

(i) The period in which the inlet to the control device 

will contain at least 50 percent of the maximum HAP load (in 

lbs) capable of being vented to the control device over any 8-

hour period. An emission profile as described in paragraph 
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(c)(3)(i)(B)(3)(i) of this section shall be used to identify the 

8-hour period that includes the maximum projected HAP load.

(ii) A period of time in which the inlet to the control 

device will contain the highest HAP mass loading rate capable of 

being vented to the control device. An emission profile as 

described in paragraph (c)(3)(i)(B)(3)(i) of this section shall 

be used to identify the period of maximum HAP loading.

(iii) The period of time when the HAP loading or stream 

composition (including non-HAP) is most challenging for the 

control device. These conditions include, but are not limited to 

the following: periods when the stream contains the highest 

combined VOC and HAP load described by the emission profiles in 

paragraph (c)(3)(i)(B)(3) of this section; periods when the 

streams contain HAP constituents that approach limits of 

solubility for scrubbing media; or periods when the streams 

contain HAP constituents that approach limits of adsorptivity 

for carbon adsorption systems.

(2) Hypothetical worst-case conditions are simulated test 

conditions that, at a minimum, contain the highest hourly HAP 

load of emissions that would be predicted to be vented to the 

control device from the emissions profile described in paragraph 

(c)(3)(i)(B)(3)(ii) or (iii) of this section.

(3) The owner or operator shall develop an emission profile 

for the vent to the control device that describes the 
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characteristics of the vent stream at the inlet to the control 

device under worst case conditions. The emission profile shall 

be developed based on any one of the procedures described in 

paragraphs (c)(3)(i)(B)(3)(i) through (iii) of this section, as 

required by paragraph (c)(3)(i)(B) of this section.

(i) The emission profile shall consider all emission 

episodes that could contribute to the vent stack for a period of 

time that is sufficient to include all processes venting to the 

stack and shall consider production scheduling. The profile 

shall describe the HAP load to the device that equals the 

highest sum of emissions from the episodes that can vent to the 

control device in any given period, not to exceed 1 hour. 

Emissions per episode shall be divided by the duration of the 

episode only if the duration of the episode is longer than 1 

hour, and emissions per episode shall be calculated using the 

procedures specified in Equation 1:

Where:

E = Mass of HAP emitted.

V = Purge flow rate at the temperature and pressure of the 

vessel vapor space.

R = Ideal gas law constant.
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T = Temperature of the vessel vapor space (absolute).

Pi = Partial pressure of the individual HAP.

Pj = Partial pressure of individual condensable VOC 

compounds (including HAP).

PT = Pressure of the vessel vapor space.

MWi = Molecular weight of the individual HAP.

t = Time of purge.

n = Number of HAP compounds in the emission stream.

i = Identifier for a HAP compound.

j = Identifier for a condensable compound.

m = Number of condensable compounds (including HAP) in the 

emission stream.

(ii) The emission profile shall consist of emissions that 

meet or exceed the highest emissions that would be expected 

under actual processing conditions. The profile shall describe 

equipment configurations used to generate the emission events, 

volatility of materials processed in the equipment, and the 

rationale used to identify and characterize the emission events. 

The emissions may be based on using compounds more volatile than 

compounds actually used in the process(es), and the emissions 

may be generated from all equipment in the process(es) or only 

selected equipment.

(iii) The emission profile shall consider the capture and 

control system limitations and the highest emissions that can be 
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routed to the control device, based on maximum flow rate and 

concentrations possible because of limitations on conveyance and 

control equipment (e.g., fans, LEL alarms and safety bypasses).

(4) Three runs, each at a minimum of the complete duration 

of the batch venting episode or 1 hour, whichever is shorter, 

and a maximum of 8 hours, are required for performance testing. 

Each run shall occur over the same worst-case conditions, as 

defined in paragraph (c)(3)(i)(B) of this section.

(5) If a condenser is used to control the process vent 

stream(s), the worst case emission episode(s) shall represent a 

period of time in which a process vent from the batch cycle or 

combination of cycles (if more than one cycle is vented through 

the same process vent) will require the maximum heat removal 

capacity, in Btu/hr, to cool the process vent stream to a 

temperature that, upon calculation of HAP concentration, will 

yield the required removal efficiency for the entire cycle. The 

calculation of maximum heat load shall be based on the emission 

profile described in paragraph (c)(3)(i)(B)(3) of this section 

that will allow calculation of sensible and latent heat loads.

(ii) The concentration of either TOC (minus methane or 

ethane) or total organic HAP (of the HAP of concern) shall be 

calculated according to paragraph (c)(3)(ii)(A) or (B) of this 

section.
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(A) The TOC concentration (CTOC) is the sum of the 

concentrations of the individual components and shall be 

computed for each run using Equation 2:

Where:

CTOC = Concentration of TOC (minus methane and ethane), dry 

basis, parts per million by volume.

Cji = Concentration of sample components j of sample i, dry 

basis, parts per million by volume.

n = Number of components in the sample.

x = Number of samples in the sample run.

(B) The total organic HAP concentration (CHAP) shall be 

computed according to Equation 2, except that only the organic 

HAP species shall be summed.

(iii) The concentration of TOC or total organic HAP shall 

be corrected to 3 percent oxygen if a combustion device is used.

(A) The emission rate correction factor or excess air, 

integrated sampling and analysis procedures of Method 3B of 40 

CFR part 60, appendix A shall be used to determine the oxygen

concentration (%02d). The samples shall be taken during the same 

time that the TOC (minus methane or ethane) or total organic HAP 

samples are taken.
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(B) The concentration corrected to 3 percent oxygen shall 

be computed using Equation 3, as follows:

Where:

Cc = Concentration of TOC or organic HAP corrected to 3 

percent oxygen, dry basis, parts per million by volume.

Cm = Concentration of TOC (minus methane and ethane) or 

organic HAP, dry basis, parts per million by volume.

%02d = Concentration of oxygen, dry basis, percent by 

volume.

(4) Test methods. When testing is conducted to measure 

emissions from an affected source, the test methods specified in 

paragraphs (c)(4)(i) through (iv) of this section shall be used, 

as applicable.

(i) For sample and velocity traverses, Method 1 or 1A of 

appendix A of part 60 shall be used, as appropriate, except that 

references to particulate matter in Method 1A do not apply for 

the purposes of this subpart.

(ii) The velocity and gas volumetric flow rate shall be 

determined using Method 2, 2A, 2C, or 2D of 40 CFR part 60, 

appendix A, as appropriate.
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(iii) The concentration measurements shall be determined 

using the methods described in paragraphs (c)(4)(iii) (A) 

through (C) of this section.

(A) Method 18 of appendix A of part 60 may be used to 

determine the HAP concentration in any control device efficiency 

determination.

(B) Method 25 of appendix A of part 60 may be used to 

determine total gaseous nonmethane organic concentration for 

control efficiency determinations in combustion devices.

(C) Method 25A of appendix A of part 60 may be used to 

determine the HAP or TOC concentration for control device 

efficiency determinations under the conditions specified in 

Method 25 of appendix A of part 60 for direct measurements of an 

effluent with a flame ionization detector, or in demonstrating 

compliance with the 20 ppmv standard, the instrument shall be 

calibrated on methane or the predominant HAP. If calibrating on 

the predominant HAP, the use of Method 25A of appendix A of part 

60 shall comply with paragraphs (c)(4)(iii)(C) (1) through (3) 

of this section.

(1) The organic HAP used as the calibration gas for Method 

25A of appendix A of part 60 shall be the single organic HAP 

representing the largest percent by volume.

(2) The use of Method 25A, 40 CFR part 60, appendix A, is 

acceptable if the response from the high level calibration gas 
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is at least 20 times the standard deviation of the response from 

the zero calibration gas when the instrument is zeroed on the 

most sensitive scale.

(3) The span value of the analyzer shall be less than 100 

ppmv.

(iv) Alternatively, any other method or data that have been 

validated according to the applicable procedures in 40 CFR part 

63, appendix A, Method 301 may be used.

(5) Calculation of percent reduction efficiency. The 

following procedures shall be used to calculate percent 

reduction efficiency:

(i) Test duration shall be as specified in paragraphs 

(c)(3)(i) (A) through (B) of this section, as appropriate.

(ii) The mass rate of either TOC (minus methane and ethane) 

or total organic HAP of the HAP of concern (Ei, Eo) shall be 

computed.

(A) The following equations shall be used:

Where:
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Cij, Coj = Concentration of sample component j of the gas 

stream at the inlet and outlet of the combustion, recovery, or 

recapture device, respectively, dry basis, parts per million by 

volume.

Ei, Eo = Mass rate of TOC (minus methane and ethane) or 

total organic HAP at the inlet and outlet of the combustion, 

recovery, or recapture device, respectively, dry basis, kilogram 

per hour.

Mij, Moj = Molecular weight of sample component j of the gas 

stream at the inlet and outlet of the combustion, recovery, or 

recapture device, respectively, gram/gram-mole.

Qi, Qo = Flow rate of gas stream at the inlet and outlet of 

the combustion, recovery, or recapture device, respectively, dry 

standard cubic meter per minute.

K2 = Constant, 2.494 × 10−6 (parts per million)−1 (gram-mole 

per standard cubic meter) (kilogram/gram) (minute/hour), where 

standard temperature (gram-mole per standard cubic meter) is 20 

°C.

(B) Where the mass rate of TOC is being calculated, all 

organic compounds (minus methane and ethane) measured by Method 

18 of 40 CFR part 60, appendix A are summed using Equations 4 

and 5 in paragraph (c)(5)(ii)(A) of this section.
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(C) Where the mass rate of total organic HAP is being 

calculated, only the organic HAP species shall be summed using 

Equations 4 and 5 in paragraph (c)(5)(ii)(A) of this section.

(iii) The percent reduction in TOC (minus methane and 

ethane) or total organic HAP shall be calculated using Equation 

6 as follows:

Where:

R = Control efficiency of combustion, recovery, or 

recapture device, percent.

Ei = Mass rate of TOC (minus methane and ethane) or total 

organic HAP at the inlet to the combustion, recovery, or 

recapture device as calculated under paragraph (c)(5)(ii) of 

this section, kilograms TOC per hour or kilograms organic HAP 

per hour.

Eo = Mass rate of TOC (minus methane and ethane) or total 

organic HAP at the outlet of the combustion, recovery, or 

recapture device, as calculated under paragraph (c)(5)(ii) of 

this section, kilograms TOC per hour or kilograms organic HAP 

per hour.

(iv) If the process vent stream entering a boiler or 

process heater with a design capacity less than 44 megawatts is 

introduced with the combustion air or as a secondary fuel, the 
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weight-percent reduction of total organic HAP or TOC (minus 

methane and ethane) across the device shall be determined by 

comparing the TOC (minus methane and ethane) or total organic 

HAP in all combusted process vent streams and primary and 

secondary fuels with the TOC (minus methane and ethane) or total 

organic HAP, respectively, exiting the combustion device.

(d) Determination of uncontrolled organic HAP emissions. 

For each process vent at a PMPU that is complying with the 

process vent control requirements in §63.1425(b)(1)(i), 

(b)(1)(iii), (b)(2)(ii), (b)(2)(iv), (c)(1)(ii), or (d)(2) using 

a combustion, recovery, or recapture device, the owner or 

operator shall determine the uncontrolled organic HAP emissions 

in accordance with the provisions of this paragraph, with the 

exceptions noted in paragraph (d)(1) of this section. The 

provisions of §63.1427(c)(1) shall be used to calculate 

uncontrolled epoxide emissions prior to the onset of an extended 

cook out.

(1) Exemptions. The owner or operator is not required to 

determine uncontrolled organic HAP emissions for process vents 

in a PMPU if the conditions in paragraph (d)(1)(i), (ii), or 

(iii) of this section are met.

(i) For PMPUs where all process vents subject to the 

epoxide emission reduction requirements of §63.1425(b) are 

controlled at all times using a combustion, recovery, or 
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recapture device, or extended cookout, the owner or operator is 

not required to determine uncontrolled epoxide emissions.

(ii) For PMPUs where the combination of process vents from 

batch unit operations associated with the use of nonepoxide 

organic HAP to make or modify the product is subject to the 

Group 1 requirements of §63.1425(c)(1), the owner or operator is 

not required to determine uncontrolled nonepoxide organic HAP 

emissions for those process vents if every process vent from a 

batch unit operation associated with the use of nonepoxide 

organic HAP to make or modify the product in the PMPU is 

controlled at all times using a combustion, recovery, or 

recapture device.

(iii) For PMPUs where all process vents associated with 

catalyst extraction that are subject to the organic emission 

reduction requirements of §63.1425(d)(2) are controlled at all 

times using a combustion, recovery, or recapture device, the 

owner or operator is not required to determine uncontrolled 

organic HAP emissions for those process vents.

(2) Process vents from batch unit operations. The 

uncontrolled organic HAP emissions from an individual batch 

cycle for each process vent from a batch unit operation shall be 

determined using the procedures in the NESHAP for Group I 

Polymers and Resins (40 CFR part 63, subpart U), §63.488(b)(1) 

through (9). Uncontrolled emissions from process vents from 
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batch unit operations shall be determined after the exit from 

the batch unit operation but before any recovery device.

(3) Process vents from continuous unit operations. The 

uncontrolled organic HAP emissions for each process vent from a 

continuous unit operation in a PMPU shall be determined at the 

location specified in paragraph (d)(3)(i) of this section, using 

the procedures in paragraph (d)(3)(ii) of this section.

(i) For process vents subject to either the provisions for 

epoxide emissions in §63.1425(b) or the provisions for organic 

HAP emissions from catalyst extraction in §63.1425(d), 

uncontrolled emissions shall be determined after the exit from 

the continuous unit operation but before any recovery device.

(ii) The owner or operator shall determine the hourly 

uncontrolled organic HAP emissions from each process vent from a 

continuous unit operation in accordance with paragraph 

(c)(5)(ii) of this section, except that the emission rate shall 

be determined at the location specified in paragraph (d)(3)(i) 

of this section.

(e) Determination of organic HAP emission reduction for a 

PMPU. (1) The owner or operator shall determine the organic HAP 

emission reduction for process vents in a PMPU that are 

complying with §63.1425(b)(1)(i), (b)(2)(ii), (c)(1)(ii), or 

(d)(2) using Equation 7. The organic HAP emission reduction 

shall be determined for each group of process vents subject to 
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the same paragraph (i.e., paragraph (b), (c), or (d)) of 

§63.1425. For instance, process vents that emit epoxides are 

subject to paragraph (b) of §63.1425. Therefore, if the owner or 

operator of an existing affected source is complying with the 98 

percent reduction requirement in §63.1425(b)(2)(ii), the organic 

HAP (i.e., epoxide) emission reduction shall be determined for 

the group of vents in a PMPU that are subject to this paragraph.

Where:

REDPMPU = Organic HAP emission reduction for the group of 

process vents subject to the same paragraph of §63.1425, 

percent.

Eunc,i = Uncontrolled organic HAP emissions from process vent 

i that is controlled using a combustion, recovery, or recapture 

device, or extended cookout, kg/batch cycle for process vents 

from batch unit operations, kg/hr for process vents from 

continuous unit operations.

n = Number of process vents in the PMPU that are subject to 

the same paragraph of §63.1425 and that are controlled using a 

combustion, recovery, or recapture device, or extended cookout.

Ri = Control efficiency of the combustion, recovery, or 

recapture device, or extended cookout, used to control organic 
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HAP emissions from vent i, determined in accordance with 

paragraph (e)(2) of this section.

Eunc,j = Uncontrolled organic HAP emissions from process vent 

j that is not controlled using a combustion, recovery, or 

recapture device, kg/batch cycle for process vents from batch 

unit operations, kg/hr for process vents from continuous unit 

operations.

m = Number of process vents in the PMPU that are subject to 

the same paragraph of §63.1425 and that are not controlled using 

a combustion, recovery, or recapture device.

(2) The control efficiency, Ri, shall be assigned as 

specified below in paragraph (e)(2)(i), (ii), (iii), or (iv) of 

this section.

(i) If the process vent is controlled using a flare (and 

the owner or operator has not previously obtained approval to 

assume a control efficiency greater than 98 percent in 

accordance with §63.6(g)) or a combustion device specified in 

paragraph (b)(1), (2), (4), or (5) of this section, and a 

performance test has not been conducted, the control efficiency 

shall be assumed to be 98 percent.

(ii) If the process vent is controlled using a combustion, 

recovery, or recapture device for which a performance test has 

been conducted in accordance with the provisions of paragraph 

(c) of this section, or for which a performance test that meets 
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the requirements of paragraph (b)(3) of this section has been 

previously performed, the control efficiency shall be the 

efficiency determined by the performance test.

(iii) If epoxide emissions from the process vent are 

controlled using extended cookout, the control efficiency shall 

be the efficiency determined in accordance with §63.1427(e).

(iv) If the process vent is controlled using a flare, and 

the owner or operator has obtained approval to assume a control 

efficiency greater than 98 percent in accordance with §63.6(g), 

the control efficiency shall be the efficiency approved in 

accordance with §63.6(g).

(f) Design evaluation. A design evaluation is required for 

those control techniques that receive less than 10 tons per year 

(9.1 megagrams per year) of uncontrolled organic HAP emissions 

from one or more PMPU, if the owner or operator has chosen not 

to conduct a performance test for those control techniques in 

accordance with paragraph (b)(6) of this section. The design 

evaluation shall include documentation demonstrating that the 

control technique being used achieves the required control 

efficiency under worst-case conditions, as determined from the 

emission profile described in §63.1426(c)(3)(i)(B)(3)(i).

(1) Except for ECO whose design evaluation is presented in 

paragraph (f)(2) of this section, to demonstrate that a control 

technique meets the required control efficiency, a design 
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evaluation shall address the composition and organic HAP 

concentration of the vent stream, immediately preceding the use 

of the control technique. A design evaluation shall also address 

other vent stream characteristics and control technique 

operating parameters, as specified in any one of paragraphs 

(f)(1)(i) through (vi) of this section, depending on the type of 

control technique that is used. If the vent stream is not the 

only inlet to the control technique, the owner or operator shall 

also account for all other vapors, gases, and liquids, other 

than fuels, received into the control technique from one or more 

PMPUs, for purposes of the efficiency determination.

(i) For an enclosed combustion technique used to comply 

with the provisions of §63.1425(b)(1), (c)(1), or (d), with a 

minimum residence time of 0.5 seconds and a minimum temperature 

of 760 °C, the design evaluation shall document that these 

conditions exist.

(ii) For a combustion control technique that does not 

satisfy the criteria in paragraph (f)(1)(i) of this section, the 

design evaluation shall document the control efficiency and 

address the characteristics listed in paragraphs (f)(1)(ii)(A) 

through (C) of this section, depending on the type of control 

technique.

(A) For a thermal vapor incinerator, in the design 

evaluation the owner or operator shall consider the autoignition 
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temperature of the organic HAP, shall consider the vent stream 

flow rate, and shall establish the design minimum and average 

temperatures in the combustion zone and the combustion zone 

residence time.

(B) For a catalytic vapor incinerator, in the design 

evaluation the owner or operator shall consider the vent stream 

flow rate and shall establish the design minimum and average 

temperatures across the catalyst bed inlet and outlet.

(C) For a boiler or process heater, in the design 

evaluation the owner or operator shall consider the vent stream 

flow rate; shall establish the design minimum and average flame 

zone temperatures and combustion zone residence time; and shall 

describe the method and location where the vent stream is 

introduced into the flame zone.

(iii) For a condenser, in the design evaluation the owner 

or operator shall consider the vent stream flow rate, relative 

humidity, and temperature, and shall establish the design outlet 

organic HAP compound concentration level, design average 

temperature of the exhaust vent stream, and the design average 

temperatures of the coolant fluid at the condenser inlet and 

outlet. The temperature of the gas stream exiting the condenser 

shall be measured and used to establish the outlet organic HAP 

concentration.
Page 98 of 262

(iv) For a carbon adsorption system that regenerates the 

carbon bed directly onsite as part of the control technique 

(such as a fixed-bed adsorber), in the design evaluation the 

owner or operator shall consider the vent stream flow rate, 

relative humidity, and temperature, and shall establish the 

design exhaust vent stream organic compound concentration level, 

adsorption cycle time, number and capacity of carbon beds, type 

and working capacity of activated carbon used for the carbon 

beds, design total regeneration stream mass or volumetric flow 

over the period of each complete carbon bed regeneration cycle, 

design carbon bed temperature after regeneration, design carbon 

bed regeneration time, and design service life of the carbon. 

For vacuum desorption, the pressure drop shall also be included.

(v) For a carbon adsorption system that does not regenerate 

the carbon bed directly onsite as part of the control technique 

(such as a carbon canister), in the design evaluation the owner 

or operator shall consider the vent stream mass or volumetric 

flow rate, relative humidity, and temperature, and shall 

establish the design exhaust vent stream organic compound 

concentration level, capacity of the carbon bed, type and 

working capacity of activated carbon used for the carbon bed, 

and design carbon replacement interval based on the total carbon 

working capacity of the control technique and source operating 

schedule.
Page 99 of 262

(vi) For a scrubber, in the design evaluation the owner or 

operator shall consider the vent stream composition, constituent 

concentrations, liquid-to-vapor ratio, scrubbing liquid flow 

rate and concentration, temperature, and the reaction kinetics 

of the constituents with the scrubbing liquid. The design 

evaluation shall establish the design exhaust vent stream 

organic compound concentration level and shall include the 

additional information in paragraphs (f)(1)(vi) (A) and (B) of 

this section for trays and a packed column scrubber.

(A) Type and total number of theoretical and actual trays.

(B) Type and total surface area of packing for entire 

column and for individual packed sections, if the column 

contains more than one packed section.

(2) For ECO, the design evaluation shall establish the 

minimum duration (time) of the ECO, the maximum pressure at the 

end of the ECO, or the maximum epoxide concentration in the 

reactor liquid at the end of the ECO for each product class.

§63.1427 Process vent requirements for processes using extended 

cookout as an epoxide emission reduction technique.

(a) Applicability of extended cookout requirements. Owners 

or operators of affected sources that produce polyether polyols 

using epoxides, and that are using ECO as a control technique to 

reduce epoxide emissions in order to comply with percent 

emission reduction requirements in §63.1425(b)(1)(i) or 
Page 100 of 262

(b)(2)(ii) shall comply with the provisions of this section. The 

owner or operator that is using ECO in order to comply with the 

emission factor requirements in §63.1425(b)(1)(iii) or 

§63.1425(b)(2)(iv) shall demonstrate that the specified emission 

factor is achieved by following the requirements in §63.1431. I 

additional control devices are used to further reduce the HAP 

emissions from a process vent already controlled by ECO, then 

the owner or operator shall also comply with the testing, 

monitoring, recordkeeping, and reporting requirements associated 

with the additional control device, as specified in §§63.1426, 

63.1429, and 63.1430, respectively.

(1) For each product class, the owner or operator shall 

determine the batch cycle percent epoxide emission reduction for 

the most difficult to control product in the product class, 

where the most difficult to control product is the polyether 

polyol that is manufactured with the slowest pressure decay 

curve.

(2) The owner or operator may determine the batch cycle 

percent epoxide emission reduction by directly measuring the 

concentration of the unreacted epoxide, or by using process 

knowledge, reaction kinetics, and engineering knowledge, in 

accordance with paragraph (a)(2)(i) of this section.

(i) If the owner or operator elects to use any method other 

than direct measurement, the epoxide concentration shall be 
Page 101 of 262

determined by direct measurement for one product from each 

product class and compared with the epoxide concentration 

determined using the selected estimation method, with the 

exception noted in paragraph (a)(2)(ii) of this section. If the 

difference between the directly determined epoxide concentration 

and the calculated epoxide concentration is less than 25 

percent, then the selected estimation method will be considered 

to be an acceptable alternative to direct measurement for that 

class.

(ii) If uncontrolled epoxide emissions prior to the end of 

the ECO are less than 10 tons per year (9.1 megagrams per year), 

the owner or operator is not required to perform the direct 

measurement required in paragraph (a)(2)(i) of this section. 

Uncontrolled epoxide emissions prior to the end of the ECO shall 

be determined by the procedures in paragraph (d)(1) of this 

section.

(b) Define the end of epoxide feed. The owner or operator 

shall define the end of the epoxide feed in accordance with 

paragraph (b)(1) or (2) of this section.

(1) The owner or operator shall determine the concentration 

of epoxide in the reactor liquid at the point in time when all 

epoxide has been added to the reactor and prior to any venting. 

This concentration shall be determined in accordance with the 

procedures in paragraph (f)(1)(i) of this section.
Page 102 of 262

(2) If the conditions in paragraphs (b)(2)(i), (ii), and 

(iii) of this section are met, the end of the epoxide feed may 

be defined by the reactor epoxide partial pressure at the point 

in time when all epoxide reactants have been added to the 

reactor. This reactor epoxide partial pressure shall be 

determined in accordance with the procedures in paragraph (g) of 

this section.

(i) No epoxide is emitted before the end of the ECO;

(ii) Extended cookout is the only control technique to 

reduce epoxide emissions; and

(iii) The owner or operator elects to determine the percent 

epoxide emission reduction for the ECO using reactor epoxide 

partial pressure in accordance with paragraph (e)(2) of this 

section.

(c) Define the onset of the ECO. The owner or operator 

shall calculate the uncontrolled emissions for the batch cycle 

by calculating the epoxide emissions, if any, prior to the onset 

of the ECO, plus the epoxide emissions at the onset of the ECO. 

The onset of the ECO is defined as the point in time when the 

combined unreacted epoxide concentration in the reactor liquid 

is equal to 25 percent of the concentration of epoxides at the 

end of the epoxide feed, which was determined in accordance with 

paragraph (b) of this section.
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(1) The uncontrolled epoxide emissions for the batch cycle 

shall be determined using Equation 8.

Where:

Ee,u = Uncontrolled epoxide emissions at the onset of the 

ECO, kilograms per (kg/)batch.

Cliq,i = Concentration of epoxide in the reactor liquid at 

the onset of the ECO, which is equal to 25 percent of the 

concentration of epoxide at the end of the epoxide feed, 

determined in accordance with paragraph (b)(1) of this section, 

weight percent.

Vliq,i = Volume of reactor liquid at the onset of the ECO, 

liters.

Dliq,i = Density of reactor liquid, kg/liter.

Cvap,i = Concentration of epoxide in the reactor vapor space 

at the onset of the ECO, determined in accordance with paragraph 

(f)(2) of this section, weight percent.

Vvap,i = Volume of the reactor vapor space at the onset of 

the ECO, liters.

Dvap,i = Vapor density of reactor vapor space at the onset of 

the ECO, kg/liter.

Eepox,bef = Epoxide emissions that occur prior to the onset of 

the ECO, determined in accordance with the provisions of 

§63.1426(d), kilograms.
Page 104 of 262

(2) If the conditions in paragraphs (b)(2)(i), (ii), and 

(iii) of this section are met, the owner or operator may define 

the onset of the ECO as the point in time when the reactor 

epoxide partial pressure equals 25 percent of the reactor 

epoxide partial pressure at the end of the epoxide feed, and is 

not required to determine the uncontrolled epoxide emissions in 

accordance with paragraph (c)(1) of this section.

(d) Determine emissions at the end of the ECO. The owner or 

operator shall calculate the epoxide emissions at the end of the 

ECO, where the end of the ECO is defined as the point 

immediately before the time when the reactor contents are 

emptied and/or the reactor vapor space purged to the atmosphere 

or to a combustion, recovery, or recapture device.

(1) The epoxide emissions at the end of the ECO shall be 

determined using Equation 9.

Where:

Ee,E = Epoxide emissions at the end of the ECO, kg.

Cliq,f = Concentration of epoxide in the reactor liquid at 

the end of the ECO, determined in accordance with paragraph 

(f)(1) of this section, weight percent.

Vliq,f = Volume of reactor liquid at the end of the ECO, 

liters.

Dliq,f = Density of reactor liquid, kg/liter.
Page 105 of 262

Cvap,f = Concentration of epoxide in the reactor vapor space 

as it exits the reactor at the end of the ECO, determined in 

accordance with paragraph (f)(2) of this section, weight 

percent.

Vvap,f = Volume of the reactor vapor space as it exits the 

reactor at the end of the ECO, liters.

Dvap,f = Vapor density of reactor vapor space at the end of 

the ECO, kg/liter.

(2) If the conditions in paragraphs (b)(2)(i), (ii), and 

(iii) of this section are met, the owner or operator may 

determine the reactor epoxide partial pressure at the end of the 

ECO instead of determining the uncontrolled epoxide emissions at 

the end of the ECO in accordance with paragraph (d)(1) of this 

section.

(e) Determine percent epoxide emission reduction. (1) The 

owner or operator shall determine the percent epoxide emission 

reduction for the batch cycle using Equation 10.

Where:

Rbatchcycle = Epoxide emission reduction for the batch cycle, 

percent.
Page 106 of 262

Ee,E = Epoxide emissions at the end of the ECO determined in 

accordance with paragraph (d)(1) of this section, kilograms.

Raddon,i = Control efficiency of combustion, recovery, or 

recapture device that is used to control epoxide emissions after 

the ECO, determined in accordance with the provisions of 

§63.1426(c), percent.

Ee,o = Epoxide emissions that occur before the end of the 

ECO, determined in accordance with the provisions of 

§63.1426(d), kilograms.

Raddon,j = Control efficiency of combustion, recovery, or 

recapture device that is used to control epoxide emissions that 

occur before the end of the ECO, determined in accordance with 

provisions of §63.1426(c), percent.

Ee,u = Uncontrolled epoxide emissions determined in 

accordance with paragraph (c)(1) of this section, kilograms.

(2) If the conditions in paragraphs (b)(2)(i), (ii), and 

(iii) of this section are met, the owner or operator may 

determine the percent epoxide emission reduction for the batch 

cycle using reactor epoxide partial pressure and Equation 11, 

instead of using the procedures in paragraph (e)(1) of this 

section.

Where:
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Rbatchcycle = Epoxide emission reduction for the batch cycle, 

percent.

Pepox,i = Reactor epoxide partial pressure at the onset of 

the ECO, determined in accordance with paragraph (c)(2) of this 

section, mm Hg.

Pepox,f = Reactor epoxide partial pressure at the end of the 

ECO, determined in accordance with paragraph (c)(2) of this 

section, mm Hg.

(f) Determination of epoxide concentrations. The owner or 

operator shall determine the epoxide concentrations in 

accordance with the procedures in this paragraph.

(1) The owner or operator shall determine the concentration 

of epoxide in the reactor liquid using either direct measurement 

in accordance with paragraph (f)(1)(i) of this section, or 

reaction kinetics in accordance with paragraph (f)(1)(ii) of 

this section. An owner or operator may also request to use an 

alternative methodology in accordance with paragraph (f)(1)(iii) 

of this section.

(i) The owner or operator shall submit a standard operating 

procedure for obtaining the liquid sample, along with the test 

method used to determine the epoxide concentration. This 

information shall be submitted in the Precompliance Report.

(ii) Determine the epoxide concentration in the reactor 

liquid using Equation 12.
Page 108 of 262

Cliq,f = Concentration of epoxide in the reactor liquid at 

the end of the time period, weight percent.

Cliq,i = Concentration of epoxide in the reactor liquid at 

the beginning of the time period, weight percent.

k = Reaction rate constant, 1/hr.

t = Time, hours.

Note: This equation assumes a first order reaction with 

respect to epoxide concentration. where:

(iii) If the owner/operator deems that the methods listed 

in paragraphs (f)(1)(i) and (ii) of this section are not 

appropriate for the reaction system for a PMPU, then the 

owner/operator may submit a request for the use of an 

alternative method.

(2) The owner or operator shall determine the concentration 

of epoxide in the reactor vapor space using either direct 

measurement in accordance with paragraph (f)(2)(i) of this 

section, or by engineering estimation in accordance with 

paragraph (f)(2)(ii) of this section. An owner or operator may 

also request to use an alternative methodology in accordance 

with paragraph (f)(2)(iii) of this section.

(i) The owner or operator shall take two representative 

samples from a bleed valve off the reactor's process vent. The 
Page 109 of 262

owner or operator shall determine the total epoxide 

concentration using 40 CFR part 60, appendix A, Method 18.

(ii) Determine the epoxide concentration in the vapor space 

using Raoult's Law or another appropriate phase equilibrium 

equation and the liquid epoxide concentration, determined in 

accordance with paragraph (f)(1) of this section.

(iii) If the owner/operator deems that the methods listed 

in paragraphs (f)(1)(i) and (ii) of this section are not 

appropriate for the reaction system for a PMPU, then the 

owner/operator may submit a request for the use of an 

alternative method.

(g) Determination of pressure. The owner or operator shall 

determine the total pressure of the system using standard 

pressure measurement devices calibrated according to the 

manufacturer's specifications or other written procedures that 

provide adequate assurance that the equipment would reasonably 

be expected to monitor accurately.

(h) Determination if pressure decay curves are similar. The 

owner or operator shall determine the pressure decay curve as 

defined in §63.1423. Products with similar pressure decay curves 

constitute a product class. To determine if two pressure decay 

curves are similar when the pressure decay curves for products 

have different starting and finishing pressures, the owner or 
Page 110 of 262

operator shall determine the time when the pressure has fallen 

to half its total pressure by using Equation 13:

Where:

Phalf1 = Half the total pressure of the epoxide for product 

1.

Time (Phalf1) = Time when the pressure has fallen to half its 

total pressure for product 1.

Phalf2 = Half the total pressure of the epoxide for product 

2.

Time (Phalf2) = Time when the pressure has fallen to half its 

total pressure for product 2.

TAVG = The average time to cookout to the point where the 

epoxide pressure is 25 percent of the epoxide pressure at the 

end of the feed step for products 1 and 2.

(i) ECO monitoring requirements. The owner or operator 

using ECO shall comply with the monitoring requirements of this 

paragraph to demonstrate continuous compliance with this 

subpart. Paragraphs (i)(1) through (3) of this section address 

monitoring of the extended cookout.

(1) To comply with the provisions of this section, the 

owner or operator shall monitor one of the parameters listed in 

paragraphs (i)(1)(i) through (iii) of this section, or may 

utilize the provision in paragraph (i)(1)(iv) of this section.
Page 111 of 262

(i) Time from the end of the epoxide feed;

(ii) The epoxide partial pressure in the closed reactor;

(iii) Direct measurement of epoxide concentration in the

reactor liquid at the end of the ECO, when the reactor liquid is 

still in the reactor, or after the reactor liquid has been 

transferred to another vessel; or

(iv) An owner or operator may submit a request to the 

Administrator to monitor a parameter other than the parameters 

listed in paragraphs (i)(1)(i) through (iii) of this section, as 

described in §63.1439(f).

(2) During the determination of the percent epoxide 

emission reduction in paragraphs (b) through (e) of this 

section, the owner or operator shall establish, as a level that 

shall be maintained during periods of operation, one of the 

parameters in paragraphs (i)(2)(i) through (iii) of this 

section, or may utilize the procedure in paragraph (i)(2)(iv) of 

this section, for each product class.

(i) The time from the end of the epoxide feed to the end of 

the ECO;

(ii) The reactor epoxide partial pressure at the end of the 

ECO;

(iii) The epoxide concentration in the reactor liquid at 

the end of the ECO, when the reactor liquid is still in the 
Page 112 of 262

reactor, or after the reactor liquid has been transferred to 

another vessel; or

(iv) An owner or operator may submit a request to the 

Administrator to monitor a parameter other than the parameters 

listed in paragraphs (i)(2)(i) through (iii) of this section, as 

described in §63.1439(f).

(3) For each batch cycle where ECO is used to reduce 

epoxide emissions, the owner or operator shall record the value 

of the monitored parameter at the end of the ECO. This parameter 

is then compared with the level established in accordance with 

paragraph (i)(2) of this section to determine if an excursion 

has occurred. An ECO excursion is defined as one of the 

situations described in paragraphs (i)(3)(i) through (v) of this 

section.

(i) When the time from the end of the epoxide feed to the 

end of the ECO is less than the time established in paragraph 

(i)(2)(i) of this section;

(ii) When the reactor epoxide partial pressure at the end 

of the ECO is greater than the partial pressure established in 

paragraph (i)(2)(ii) of this section;

(iii) When the epoxide concentration in the reactor liquid 

at the end of the ECO is greater than the epoxide concentration 

established in paragraph (i)(2)(iii) of this section;
Page 113 of 262

(iv) When the parameter is not measured and recorded at the 

end of the ECO; or

(v) When the alternative monitoring parameter is outside 

the range established under §63.1439(f) for proper operation of 

the ECO as a control technique.

(j) Recordkeeping requirements. (1) The owner or operator 

shall maintain the records specified in paragraphs (j)(1)(i) and 

(ii) of this section, for each product class. The owner or 

operator shall also maintain the records related to the initial 

determination of the percent epoxide emission reduction 

specified in paragraphs (j)(1)(iii) through (x) of this section, 

as applicable, for each product class.

(i) Operating conditions of the product class, including:

(A) Pressure decay curve;

(B) Minimum reaction temperature;

(C) Number of reactive hydrogens in the raw material;

(D) Minimum catalyst concentration;

(E) Ratio of EO/PO at the end of the epoxide feed; and

(F) Reaction conditions, including the size of the reactor 

or batch.

(ii) A listing of all products in the product class, along 

with the information specified in paragraphs (j)(1)(i)(A) 

through (F) of this section, for each product.
Page 114 of 262

(iii) The concentration of epoxide at the end of the 

epoxide feed, determined in accordance with paragraph (b)(1) of 

this section.

(iv) The concentration of epoxide at the onset of the ECO, 

determined in accordance with paragraph (c) of this section.

(v) The uncontrolled epoxide emissions at the onset of the 

ECO, determined in accordance with paragraph (c)(1) of this 

section. The records shall also include all the background data, 

measurements, and assumptions used to calculate the uncontrolled 

epoxide emissions.

(vi) The epoxide emissions at the end of the ECO, 

determined in accordance with paragraph (d)(1) of this section. 

The records shall also include all the background data, 

measurements, and assumptions used to calculate the epoxide 

emissions.

(vii) The percent epoxide reduction for the batch cycle, 

determined in accordance with paragraph (e)(1) of this section. 

The records shall also include all the background data, 

measurements, and assumptions used to calculate the percent

reduction.

(viii) The parameter level, established in accordance with 

paragraph (i)(3) of this section.

(ix) If epoxide emissions occur before the end of the ECO, 

the owner or operator shall maintain records of the time and 
Page 115 of 262

duration of all such emission episodes that occur during the 

initial demonstration of batch cycle efficiency.

(x) If the conditions in paragraphs (b)(2)(i), (ii), and 

(iii) of this section are met, the owner or operator is not 

required to maintain the records specified in paragraphs 

(j)(1)(iii) through (iv) of this section, but shall maintain the 

records specified in paragraphs (j)(1)(x)(A), (B), and (C) of 

this section.

(A) The reactor epoxide partial pressure at the following 

times:

(1) At end of the epoxide feed, determined in accordance 

with paragraph (b)(2) of this section;

(2) At the onset of the ECO, established in accordance with 

paragraph (c)(2) of this section; or

(3) At the end of the ECO, determined in accordance with 

paragraph (d)(2) of this section.

(B) The percent epoxide reduction for the batch cycle, 

determined in accordance with paragraph (e)(2) of this section. 

The records shall also include all the measurements and 

assumptions used to calculate the percent reduction.

(C) The reactor epoxide partial pressure at the end of the 

ECO.

(2) The owner or operator shall maintain the records 

specified in paragraphs (j)(2)(i) through (iv) of this section.
Page 116 of 262

(i) For each batch cycle, the product being produced and 

the product class to which it belongs.

(ii) For each batch cycle, the owner or operator shall 

record the value of the parameter monitored in accordance with 

paragraph (i)(3) of this section.

(iii) If a combustion, recovery, or recapture device is 

used to reduce emission in conjunction with ECO, the owner or 

operator shall record the information specified in §63.1430(d) 

and comply with the monitoring provisions in §63.1429.

(iv) [Reserved]

(v) If epoxide emissions occur before the end of the ECO, 

the owner or operator shall maintain records of the time and 

duration of all such emission episodes.

(k) Reporting requirements. The owner or operator shall 

comply with the reporting requirements in this paragraph.

(1) The information specified in paragraphs (k)(1)(i) 

through (ii) of this section shall be provided in the 

Precompliance Report, as specified in §63.1439(e)(4).

(i) A standard operating procedure for obtaining the 

reactor liquid sample and a method that will be used to 

determine the epoxide concentration in the liquid, in accordance 

with paragraph (f)(1)(i) of this section.

(ii) A request to monitor a parameter other than those 

specified in paragraph (i)(1)(i), (ii), or (iii) of this 
Page 117 of 262

section, as provided for in paragraph (i)(1)(iv) of this 

section.

(2) The information specified in paragraphs (k)(2)(i) 

through (iv) of this section shall be provided in the 

Notification of Compliance Status, as specified in 

§63.1439(e)(5).

(i) For each product class, the information specified in 

paragraphs (k)(2)(i)(A) through (C) of this section.

(A) The operating conditions of this product class, as 

specified in paragraph (j)(1)(i) of this section.

(B) A list of all products in the product class.

(C) The percent epoxide emission reduction, determined in 

accordance with paragraph (e) of this section.

(ii) The parameter for each product class, as determined in 

accordance with paragraph (i)(2) of this section.

(iii) If a combustion, recovery, or recapture device is 

used in addition to ECO to reduce emissions, the information 

specified in §63.1430(g)(1).

(iv) If epoxide emissions occur before the end of the ECO, 

a listing of the time and duration of all such emission episodes 

that occur during the initial demonstration of batch cycle 

efficiency.
Page 118 of 262

(3) The information specified in paragraphs (k)(3)(i) 

through (iii) of this section shall be provided in the Periodic 

Report, as specified in §63.1439(e)(6).

(i) Reports of each batch cycle for which an ECO excursion 

occurred, as defined in paragraph (i)(3) of this section.

(ii) Notification of each batch cycle when the time and 

duration of epoxide emissions before the end of the ECO, 

recorded in accordance with paragraph (j)(2)(iv) of this 

section, exceed the time and duration of the emission episodes 

during the initial epoxide emission percentage reduction 

determination, as recorded in paragraph (j)(1)(viii) of this 

section.

(iii) If a combustion, recovery, or recapture device is 

used to reduce emissions, the information specified in 

§63.1430(h).

(l) New polyether polyol products. If an owner or operator 

wishes to utilize ECO as a control option for a polyether polyol 

not previously assigned to a product class and reported to the 

Agency in accordance with either paragraph (k)(2)(i)(B), 

(l)(1)(ii), or (l)(2)(iii) of this section, the owner or 

operator shall comply with the provisions of paragraph (l)(1) or 

(2) of this section.

(1) If the operating conditions of the new polyether polyol 

are consistent with the operating conditions for an existing 
Page 119 of 262

product class, the owner or operator shall comply with the 

requirements in paragraphs (l)(1)(i) and (ii) of this section.

(i) The owner or operator shall update the list of products 

for the product class required by paragraph (j)(1)(ii) of this 

section, and shall record the information in paragraphs 

(j)(1)(i)(A) through (F) of this section for the new product.

(ii) Within 180 days after the production of the new 

polyether polyol, the owner or operator shall submit a report 

updating the product list previously submitted for the product 

class. This information may be submitted along with the next 

Periodic Report.

(2) If the operating conditions of the new polyether polyol 

do not conform with the operating characteristics of an existing 

product class, the owner or operator shall establish a new 

product class and shall comply with provisions of paragraphs 

(l)(2)(i) through (iii) of this section.

(i) The owner or operator shall establish the batch cycle 

percent epoxide emission reduction in accordance with paragraphs 

(b) through (g) of this section for the product class.

(ii) The owner or operator shall establish the records 

specified in paragraph (j)(1) of this section for the product 

class.

(iii) Within 180 days of the production of the new 

polyether polyol, the owner or operator shall submit a report 
Page 120 of 262

containing the information specified in paragraphs (k)(2)(i) and 

(ii) of this section.

(m) Polyether polyol product changes. If a change in 

operation, as defined in paragraph (m)(1) of this section, 

occurs for a polyether polyol that has been assigned to a 

product class and reported to the Agency in accordance with 

paragraph (k)(2)(i)(B), (l)(1)(ii), or (l)(2)(iii) of this 

section, the owner or operator shall comply with the provisions 

of paragraphs (m)(2) through (3) of this section.

(1) A change in operation for a polyether polyol is defined 

as a change in any one of the parameters listed in paragraphs 

(m)(1)(i) through (ix) of this section.

(i) A significant change in reaction kinetics;

(ii) Use of a different oxide reactant;

(iii) Use of a different EO/PO ratio;

(iv) A lower reaction temperature;

(v) A lower catalyst feed on a mole/mole fraction OH basis;

(vi) A shorter cookout;

(vii) A lower reactor pressure;

(viii) A different type of reaction, (e.g., a selfcatalyzed vs. catalyzed reaction); or

(ix) A marked change in reaction conditions (e.g., a 

markedly different liquid level).
Page 121 of 262

(2) If the operating conditions of the product after the 

change in operation remain within the operation conditions of 

the product class to which the product was assigned, the owner 

or operator shall update the records specified in paragraphs 

(j)(1)(i)(A) through (F) of this section for the product.

(3) If the operating conditions of the product after the 

change in operation are outside of the operating conditions of 

the product class to which the product was assigned, the owner 

or operator shall comply with the requirements in paragraph 

(m)(3)(i) or (ii) of this section, as appropriate.

(i) If the new operating conditions of the polyether polyol 

are consistent with the operating conditions for another 

existing product class, the owner or operator shall comply with 

the requirements in paragraphs (m)(3)(i)(A) and (B) of this 

section.

(A) The owner or operator shall update the list of products 

for the product class that the product is leaving, and for the 

product class that the product is entering, and shall record the 

new information in paragraphs (j)(1)(i)(A) through (F) of this 

section for the product.

(B) Within 180 days after the change in operating 

conditions for the polyether polyol product, the owner or 

operator shall submit a report updating the product lists 
Page 122 of 262

previously submitted for the product class. This information may 

be submitted along with the next Periodic Report.

(ii) If the new operating conditions of the polyether 

polyol product do not conform with the operating characteristics 

of an existing product class, the owner or operator shall 

establish a new product class and shall comply with provisions 

of paragraphs (m)(3)(ii)(A) through (C) of this section.

(A) The owner or operator shall establish the batch cycle 

percent epoxide emission reduction in accordance with paragraphs 

(b) through (g) of this section for the product class.

(B) The owner or operator shall establish the records 

specified in paragraph (j)(1) of this section for the product 

class.

(C) Within 180 days of the change in operating conditions 

for the polyether polyol, the owner or operator shall submit a 

report containing the information specified in paragraphs 

(k)(2)(i) and (ii) of this section.

§63.1428 Process vent requirements for group determination of 

PMPUs using a nonepoxide organic HAP to make or modify the 

product.

(a) Process vents from batch unit operations. The owner or 

operator shall determine, for each PMPU located at an affected 

source, if the combination of all process vents from batch unit 

operations that are associated with the use of nonepoxide 
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organic HAP to make or modify the product is a Group 1 

combination of batch process vents, as defined in §63.1423. The 

annual uncontrolled nonepoxide organic HAP emissions, determined 

in accordance with paragraph (b) of this section, and annual 

average flow rate, determined in accordance with paragraph (c) 

of this section, shall be determined for all process vents from 

batch unit operations associated with the use of a nonepoxide 

organic HAP to make or modify the product, with the exception of 

those vents specified in paragraph (i) of this section, at the 

location after all applicable control techniques have been 

applied to reduce epoxide emissions in accordance with paragraph 

(a)(1) or (2) of this section.

(1) If the owner or operator is using a combustion, 

recovery, or recapture device to reduce epoxide emissions, this 

location shall be at the exit of the combustion, recovery, or 

recapture device.

(2) If the owner or operator is using ECO to reduce epoxide 

emissions, this location shall be at the exit from the batch 

unit operation. For the purpose of these determinations, the 

primary condenser operating as a reflux condenser on a reactor 

or distillation column shall be considered part of the unit 

operation.

(b) Determination of annual nonepoxide organic HAP 

emissions. The owner or operator shall determine, for each PMPU, 
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the total annual nonepoxide organic HAP emissions from the 

combination of all process vents from batch unit operations that 

are associated with the use of a nonepoxide organic HAP to make 

or modify the product in accordance with paragraphs (b)(1) and 

(2) of this section.

(1) The annual nonepoxide organic HAP emissions for each 

process vent from a batch unit operation associated with the use 

of a nonepoxide organic HAP to make or modify the product shall 

be determined using the batch process vent procedures in the 

NESHAP for Group I Polymers and Resins (40 CFR part 63, subpart 

U), §63.488(b).

(2) The owner or operator shall sum the annual nonepoxide 

organic HAP emissions from all individual process vents from 

batch unit operations in a PMPU, determined in accordance with 

paragraph (b)(1) of this section, to obtain the total nonepoxide 

organic HAP emissions from the combination of process vents 

associated with the use of a nonepoxide organic HAP to make or 

modify the product, for the PMPU.

(c) Minimum emission level exemption. If the annual 

emissions of TOC or nonepoxide organic HAP from the combination 

of process vents from batch unit operations that are associated 

with the use of nonepoxide organic HAP to make or modify a 

polyether polyol for a PMPU are less than 11,800 kg/yr, the 
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owner or operator of that PMPU is not required to comply with 

the provisions in paragraphs (d) and (e) of this section.

(d) Determination of average flow rate and annual average 

flow rate. The owner or operator shall determine, for each PMPU, 

the total annual average flow rate for the combination of all 

process vents from batch unit operations that are associated 

with the use of a nonepoxide organic HAP to make or modify a 

product in accordance with paragraphs (d)(1) and (2) of this 

section.

(1) The annual average flow rate for each process vent from 

batch unit operations that is associated with the use of 

nonepoxide organic HAP to make or modify the product shall be 

determined using the batch process vent procedures in the NESHAP 

for Group I Polymers and Resins (40 CFR part 63, subpart U), 

§63.488(e).

(2) The owner or operator shall sum the annual average flow 

rates from the individual process vents from batch unit 

operations in a PMPU, determined in accordance with paragraph 

(d)(1) of this section, to obtain the total annual average flow 

rate for the combination of process vents associated with the 

use of a nonepoxide organic HAP to make or modify the product, 

for the PMPU.

(e) Determination of cutoff flow rate. For each PMPU at an 

affected source that uses nonepoxide organic HAP to make or 
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modify the product, the owner or operator shall calculate the 

cutoff flow rate using Equation 14.

Where:

CFR = Cutoff flow rate, standard cubic meters per minute 

(scmm).

AE = Annual TOC or nonepoxide organic HAP emissions from 

the combination of process vents from batch unit operations that 

are associated with the use of nonepoxide organic HAP to make or 

modify the product, as determined in paragraph (b)(2) of this 

section, kg/yr.

(f) [Reserved]

(g) Process changes affecting Group 2 combinations of 

process vents in a PMPU that are from batch unit operations. 

Whenever process changes, as described in paragraph (g)(1) of 

this section, are made that affect a Group 2 combination of 

batch process vents and that could reasonably be expected to 

change the group status from Group 2 to Group 1, the owner or 

operator shall comply with paragraphs (g)(2) and (3) of this 

section.

(1) Examples of process changes include, but are not 

limited to, increases in production capacity or production rate, 

changes in feedstock type or catalyst type; or whenever there is 

replacement, removal, or modification of recovery equipment 
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considered part of the batch unit operation. Any change that 

results in an increase in the annual nonepoxide organic HAP 

emissions from the estimate used in the previous group 

determination constitutes a process change for the purpose of 

these provisions. Process changes do not include: process 

upsets; unintentional, temporary process changes; and changes 

that are within the margin of variation on which the original 

group determination was based.

(2) For each process affected by a process change, the 

owner or operator shall redetermine the group status by 

repeating the procedures specified in paragraphs (b) through (e) 

of this section, as applicable, and determining if the 

combination of process vents is a Group 1 combination of batch 

process vents, as defined in §63.1423. Alternatively, 

engineering assessment, as described in §63.488(b)(6)(i), may be 

used to determine the effects of the process change.

(3) Based on the results of paragraph (g)(2) of this 

section, the owner or operator shall comply with either 

paragraph (g)(3)(i) or (ii) of this section.

(i) If the redetermination described in paragraph (g)(2) of 

this section indicates that the group status of the combination 

of process vents from batch unit operations in a PMPU that are 

associated with the use of nonepoxide organic HAP to make or 

modify the product changes from Group 2 to Group 1 as a result 
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of the process change, the owner or operator shall submit a 

report as specified in §63.1439(e)(6)(iii)(D)(1) and shall 

comply with Group 1 combination of batch process vents 

provisions in this subpart, as specified in §63.1425(c)(1).

(ii) If the redetermination described in paragraph (g)(2) 

of this section indicates no change in group status, the owner 

or operator is not required to submit a report.

(h) Process vents from continuous unit operations. (1) The 

owner or operator shall determine the total resource 

effectiveness (TRE) index value for each process vent from a 

continuous unit operation that is associated with the use of 

nonepoxide organic HAP to make or modify the product. To 

determine the TRE index value, the owner or operator shall 

conduct a TRE determination and calculate the TRE index value 

according to the HON process vent group determination procedures 

in §63.115(d)(1) or (2) and the TRE equation in §63.115(d)(3). 

The TRE index value shall be determined at the location after 

all applicable control techniques have been applied to reduce 

epoxide emissions in accordance with paragraph (h)(1)(i), (ii), 

or (iii) of this section.

(i) If the owner or operator uses one or more nonepoxide 

recovery devices after all control techniques to reduce epoxide 

emissions, this location shall be after the last nonepoxide 

recovery device.
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(ii) If the owner or operator does not use a nonepoxide 

recovery device after a combustion, recovery, or recapture 

device to reduce epoxide emissions, this location shall be at 

the exit of the combustion, recovery, or recapture device.

(iii) If the owner or operator does not use a nonepoxide 

recovery device after extended cookout to reduce epoxide 

emissions, this location shall be at the exit from the 

continuous unit operation. For the purpose of these 

determinations, the primary condenser operating as a reflux 

condenser on a reactor or distillation column shall be 

considered part of the unit operation.

(2) The owner or operator of a Group 2 continuous process 

vent shall recalculate the TRE index value as necessary to 

determine whether the process vent is Group 1 or Group 2, 

whenever process changes are made that could reasonably be 

expected to change the process vent to Group 1. Examples of 

process changes include, but are not limited to, increases in 

production capacity or production rate, changes in feedstock 

type or catalyst type, or whenever there is replacement, 

removal, or addition of recovery equipment. For purposes of this 

paragraph, process changes do not include: process upsets; 

unintentional, temporary process changes; and changes that are 

within the range on which the original TRE calculation was 

based.
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(i) The TRE index value shall be recalculated based on 

measurements of process vent stream flow rate, TOC, and 

nonepoxide organic HAP concentrations, and heating values as 

specified in the HON process vent group determination procedures 

in §63.115(a), (b), (c), and (d), as applicable, or on best 

engineering assessment of the effects of the change. Engineering 

assessments shall meet the specifications in §63.115(d)(1).

(ii) Where the recalculated TRE index value is less than or 

equal to 1.0, or, where the TRE index value before the process 

change was greater than 4.0 and the recalculated TRE index value 

is less than or equal to 4.0 but greater than 1.0, the owner or 

operator shall submit a report as specified in the process vent 

reporting and recordkeeping provisions in §63.1430(ji) or 

(kj),and shall comply with the appropriate provisions in the 

process vent control requirements in §63.1425 by the dates 

specified in §63.1422 (the section describing compliance dates 

for sources subject to this subpart).

(iii) Where the recalculated TRE index value is greater 

than 4.0, the owner or operator is not required to submit a 

report.

(i) Combination of process vents from batch unit operations 

and process vents from continuous unit operations. If an owner 

or operator combines a process vent from a batch unit operation 

that is associated with the use of a nonepoxide organic HAP to 
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make or modify the product with a process vent from a continuous 

unit operation that is associated with the use of a nonepoxide 

prior to the epoxide control technique, or prior to a nonepoxide 

recovery device that is after the epoxide control technique, 

then the provisions in paragraphs (i)(1) and (2) of this section 

shall apply.

(1) The process vent from the batch unit operation is not 

required to be included in the group determination required by 

paragraphs (a) through (e) of this section.

(2) The TRE index value of the combined stream shall be 

determined in accordance with paragraph (h) of this section, and 

the TRE index value shall be calculated during a period when 

nonepoxide organic HAP emissions are being generated by the 

batch unit operation.

§63.1429 Process vent monitoring requirements.

(a) Monitoring equipment requirements. The owner or 

operator of a process vent that uses a combustion, recovery, or 

recapture device to comply with the process vent control 

requirements in §63.1425(b)(1), (b)(2), (c)(1), (c)(3), or (d) 

shall install monitoring equipment specified in paragraph 

(a)(1), (2), (3), (4), (5), (6), or (7) of this section, 

depending on the type of device used. Also, the owner or 

operator that uses a recovery or recapture device to comply with 

§63.1425(c)(4) shall install monitoring equipment as specified 
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in paragraph (a)(4), (5), (6), or (7) of this section. All 

monitoring equipment shall be installed, calibrated, maintained, 

and operated according to manufacturers' specifications or other 

written procedures that provide adequate assurance that the 

equipment would reasonably be expected to monitor accurately.

(1) Where an incinerator is used, a temperature monitoring 

device equipped with a continuous recorder is required.

(i) Where an incinerator other than a catalytic incinerator 

is used, a temperature monitoring device shall be installed in 

the firebox or in the ductwork immediately downstream of the 

firebox in a position before any substantial heat exchange 

occurs.

(ii) Where a catalytic incinerator is used, temperature 

monitoring devices shall be installed in the gas stream 

immediately before and after the catalyst bed.

(2) Where a flare is used, the following monitoring 

equipment is required: a device (including but not limited to a 

thermocouple, ultra-violet beam sensor, or infrared sensor) 

capable of continuously detecting the presence of a pilot flame.

(3) Where a boiler or process heater of less than 44 

megawatts design heat input capacity is used, the following 

monitoring equipment is required: a temperature monitoring 

device in the firebox equipped with a continuous recorder. Any 

boiler or process heater in which all process vent streams are
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introduced with primary fuel or are used as the primary fuel is 

exempt from this requirement.

(4) Where an absorber is used, a scrubbing liquid flow rate 

meter or a pressure monitoring device is required and should be 

equipped with a continuous recorder. If an acid or base 

absorbent is used, a pH monitoring device to monitor scrubber 

effluent is also required. If two or more absorbers in series 

are used, a scrubbing liquid flow rate meter, or a pressure 

monitoring device, equipped with a continuous recorder, is 

required for each absorber in the series. An owner or operator 

may submit a request to instead install the scrubbing liquid 

flow rate meter, or a pressure monitoring device, equipped with 

a continuous recorder, on only the final absorber in a series,

in accordance with the alternative parameter monitoring 

reporting requirements in §63.1439(f).

(5) Where a condenser is used, a condenser exit temperature 

(product side) monitoring device equipped with a continuous 

recorder is required.

(6) Where a carbon adsorber is used, an integrating 

regeneration stream flow monitoring device having an accuracy of 

+10 percent or better, capable of recording the total 

regeneration stream mass or volumetric flow for each 

regeneration cycle, and a carbon bed temperature monitoring 

device, capable of recording the carbon bed temperature after 
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each regeneration and within 15 minutes of completing any 

cooling cycle are required.

(7) As an alternative to paragraphs (a)(4) through (6) of 

this section, the owner or operator may install an organic 

monitoring device equipped with a continuous recorder.

(b) Alternative parameters. An owner or operator of a 

process vent may request approval to monitor parameters other 

than those listed in paragraph (a) of this section. The request 

shall be submitted according to the procedures specified in the 

process vent reporting and recordkeeping requirements in 

§63.1430(j) and the alternative parameter monitoring reporting 

requirements in §63.1439(f). Approval shall be requested if the 

owner or operator:

(1) Uses a combustion device other than an incinerator, 

boiler, process heater, or flare; or

(2) For a Group 2 continuous process vent, maintains a TRE 

greater than 1.0 but less than or equal to 4.0 without a 

recovery device or with a recovery device other than the 

recovery devices listed in paragraph (a) of this section; or

(3) Uses one of the combustion, recovery, or recapture 

devices listed in paragraph (a) of this section, but seeks to 

monitor a parameter other than those specified in paragraph (a) 

of this section.
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(c) Monitoring of bypass lines. The owner or operator of a 

process vent using a process vent system that contains bypass 

lines that could divert a process vent stream away from the 

combustion, recovery, or recapture device used to comply with 

the process vent control requirements in §63.1425(b), (c), or 

(d) shall comply with paragraph (c)(1) or (2) of this section. 

Equipment such as low leg drains, high point bleeds, analyzer 

vents, open-ended valves or lines, and pressure relief 

devicesvalves needed for safety purposes are not subject to 

paragraphs (c)(1) or (2) of this section.

(1) Properly install, maintain, and operate a flow 

indicator that takes a reading at least once at approximately 

equal intervals of about 15 minutes. Records shall be generated 

as specified in the process vent reporting and recordkeeping 

provisions in §63.1430(d)(3). The flow indicator shall be 

installed at the entrance to any bypass line that could divert 

emissions away from the combustion, recovery, or recapture 

device and to the atmosphere; or

(2) Secure the bypass line valve in the non-diverting 

position with a car-seal or a lock-and-key type configuration. A 

visual inspection of the seal or closure mechanism shall be 

performed at least once every month to ensure that the valve is 

maintained in the non-diverting position and emissions are not 

diverted through the bypass line. Records shall be generated as 
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specified in the process vent reporting and recordkeeping 

provisions in §63.1430(d)(4)(i).

(d) Establishment of parameter monitoring levels. Parameter 

monitoring levels for process vents from continuous or batch 

unit operations using a combustion, recovery, or recapture 

device to comply with the process vent control requirements in 

§63.1425(b), (c), or (d) shall be established as specified in 

paragraphs (d)(1) through (3) of this section.

(1) For each parameter monitored under paragraph (a) or (b) 

of this section, the owner or operator shall establish a level, 

defined as either a maximum or minimum operating parameter as 

denoted in Table 57 of this subpart (the table listing the 

operating parameters for which monitoring levels are required to 

be established , recordkeeping, and reporting requirements for 

process vent streams from batch unit operations), that indicates 

that the combustion, recovery, or recapture device is operated 

in a manner to ensure compliance with the provisions of this 

subpart. The level shall be established in accordance with the 

procedures specified in the process vent control requirements in 

§63.1438(a) through 0(d), as applicable. The level may be based 

upon a prior performance test conducted for determining 

compliance with a regulation promulgated by the EPA, and the 

owner or operator is not required to conduct a performance test 

under the process vent requirements for determining organic HAP 
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concentration, control efficiency, and aggregated organic HAP 

emission reductions in §63.1426, provided that the prior 

performance test meets the conditions of §63.1426(b)(3).

(2) The established level, along with supporting 

documentation, shall be submitted in the Notification of 

Compliance Status or the operating permit application as 

required in the Notification of Compliance Status requirements 

in §63.1439(e)(5) or in the operating permit application 

requirements in §63.1439(e)(8), respectively.

(3) The operating day shall be defined as part of 

establishing the parameter monitoring level and shall be 

submitted with the information in paragraph (d)(2) of this 

section. The definition of operating day shall specify the 

time(s) at which an operating day begins and ends.

§63.1430 Process vent reporting and recordkeeping requirements.

(a) [Reserved]

(b) Records to demonstrate compliance. The owner or 

operator complying with the process vent control requirements in 

§63.1425(b), (c), or (d) shall keep the following records, as 

applicable, readily accessible:

(1) When using a flare to comply with the process vent 

control requirements in §63.1425(b)(2)(i), (c)(1)(i), (c)(3)(i), 

or (d)(1):
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(i) The flare design (i.e., steam-assisted, air-assisted, 

or non-assisted);

(ii) All visible emission readings, heat content 

determinations, flow rate determinations, and exit velocity 

determinations made during the flare specification determination 

required by §63.1437(c); and

(iii) All periods during the flare specification 

determination required by §63.1437(c) when all pilot flames are 

absent.

(2) The following information when using a combustion, 

recovery, or recapture device (other than a flare) to achieve 

compliance with the process vent control requirements in 

§63.1425(b), (c), or (d):

(i) For a combustion, recovery, or recapture device being 

used to comply with a percent reduction requirement of 

§63.1425(b)(1)(i), (b)(2)(ii), (c)(1)(ii), (c)(3)(ii), or 

(d)(2), or the annual epoxide emission limitation in 

§63.1425(b)(1)(iii) or (b)(2)(iv), the percent reduction of 

organic HAP or TOC achieved, as determined using the procedures 

specified in the process vent requirements in §63.1426;

(ii) For a combustion device being used to comply with an 

outlet concentration limitation of §63.1425(b)(1)(ii) or 

(b)(2)(iii), the concentration of organic HAP or TOC outlet of 
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the combustion device, as determined using the procedures 

specified in the process vent requirements in §63.1426;

(iii) For a boiler or process heater, a description of the 

location at which the process vent stream is introduced into the 

boiler or process heater;

(iv) For a boiler or process heater with a design heat 

input capacity of less than 44 megawatts and where the process 

vent stream is introduced with combustion air or is used as a 

secondary fuel and is not mixed with the primary fuel, the 

percent reduction of organic HAP or TOC achieved, as determined 

using the procedures specified in §63.1426.

(c) Records related to the establishment of parameter 

monitoring levels. For each parameter monitored according to the 

process vent monitoring requirements in §63.1429(a) and Table 5 

of this subpart, or for alternate parameters and/or parameters 

for alternate control techniques monitored according to the 

alternative parameter monitoring reporting requirements in 

§63.1439(f) as allowed under §63.1429(b), maintain documentation 

showing the establishment of the level that indicates that the 

combustion, recovery, or recapture device is operated in a 

manner to ensure compliance with the provisions of this subpart, 

as required by the process vent monitoring requirements in 

§63.1429(d).
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(d) Records to demonstrate continuous compliance. The owner 

or operator that uses a combustion, recovery, or recapture 

device to comply with the process vent control requirements in 

§63.1425(b), (c), or (d) shall keep the following records 

readily accessible:

(1) Continuous records of the equipment operating 

parameters specified to be monitored under the process vent 

monitoring requirements in §63.1429(a) as applicable, and listed 

in Table 5 of this subpart, or specified by the Administrator in 

accordance with the alternative parameter monitoring reporting 

requirements in §63.1439(f), as allowed under §63.1429(b). These 

records shall be kept as specified under §63.1439(d), except as 

specified in paragraphs (d)(1)(i) and (ii) of this section.

(i) For flares, the records specified in Table 5 of this 

subpart shall be maintained in place of continuous records.

(ii) For carbon adsorbers used for process vents from batch 

unit operations, the records specified in Table 5 of this 

subpart shall be maintained in place of daily averages.

(2) Records of the daily average value for process vents 

from continuous unit operations or batch unit operations of each 

continuously monitored parameter, except as provided in 

paragraphs (d)(2)(i) and (ii) of this section.

(i) Monitoring data recorded during periods of monitoring 

system breakdowns, repairs, calibration checks, and zero (low-
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level) and high-level adjustments shall not be included in 

computing the daily averages. In addition, monitoring data 

recorded during periods of non-operation of the process (or 

specific portion thereof) resulting in cessation of organic HAP 

emissions, (or periods of start-up, shutdown, or malfunction)

shall not be included in computing the daily averages.

(ii) If all recorded values for a monitored parameter 

during an operating day are above the minimum or below the 

maximum parameter monitoring level established in accordance 

with the process vent monitoring requirements in §63.1429(d), 

the owner or operator may record that all values were above the 

minimum or below the maximum level established, rather than 

calculating and recording a daily average for that operating 

day.

(3) Hourly records of whether the flow indicator for bypass 

lines specified under §63.1429(c)(1) was operating and whether a 

diversion was detected at any time during the hour. Also, 

records of the time(s) of all periods when the process vent was 

diverted from the combustion, recovery, or recapture device, or 

the flow indicator specified in §63.1429(c)(1) was not 

operating.

(4) Where a seal or closure mechanism is used to comply 

with the process vent monitoring requirements for bypass lines 

in §63.1429(c)(2), hourly records of flow are not required. For 
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compliance with §63.1429(c)(2), the owner or operator shall 

record whether the monthly visual inspection of the seals or 

closure mechanism has been done, and shall record the occurrence 

of all periods when the seal mechanism is broken, the bypass 

line valve position has changed, or the key for a lock-and-key 

type configuration has been checked out, and records of any carseal that has been broken.

(5) Records specifying the times and duration of periods of 

monitoring system breakdowns, repairs, calibration checks, and 

zero (low-level) and high level adjustments. In addition, 

records specifying any other periods of process or combustion, 

recovery, or recapture device operation when monitors are not 

operating.

(e) Records related to the group determination for process 

vents that are associated with the use of nonepoxide organic HAP 

to make or modify the product — (1) Process vents from batch 

unit operations. Except as provided in paragraphs (e)(1)(vi) and 

(vii) of this section, the owner or operator of an affected 

source shall maintain the records specified in paragraphs 

(e)(1)(i) through (v) of this section for each PMPU that uses a 

nonepoxide organic HAP to make or modify the product in batch 

unit operations. The records required to be maintained by this 

paragraph are limited to the information developed and used to 

make the group determination under the process vent requirements 
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for processes using a nonepoxide organic HAP to make or modify 

the product in §63.1428(a) through (e), as appropriate. If an 

owner or operator did not need to develop certain information 

(e.g., annual average flow rate) to determine the group status, 

the owner or operator is not required to develop additional 

information. The owner or operator may elect Group 1 status for 

process vents without making a Group 1/Group 2 determination. In 

such event, none of the records specified in paragraphs 

(e)(1)(i) through (v) are required.

(i) A description of, and an emission estimate for, each 

batch emission episode, and the total emissions associated with 

one batch cycle for each unique product class made in the PMPU.

(ii) Total annual uncontrolled TOC or nonepoxide organic 

HAP emissions from the combination of process vents from batch 

unit operations associated with the use of nonepoxide organic 

HAP to make or modify the product, as determined in accordance 

with the process vent requirements for group determinations in 

§63.1428(b).

(iii) The annual average flow rate for the combination of 

process vents from batch unit operations associated with the use 

of organic HAP to make or modify the product, as determined in 

accordance with the process vent requirements for group 

determinations in §63.1428(d).
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(iv) The cutoff flow rate, determined in accordance with 

the process vent requirements for group determinations in 

§63.1428(e).

(v) The results of the PMPU group determination (i.e., 

whether the combination of process vents is Group 1 or Group 2).

(vi) If the combination of all process vents from batch 

unit operations associated with the use of an organic HAP to 

make or modify the product is subject to the Group 1 batch 

process vent control requirements for nonepoxide HAP emissions 

from making or modifying the product in §63.1425((c)(1), none of 

the records in paragraphs (e)(1)(i) through (v) of this section 

are required.

(vii) If the total annual emissions from the combination of 

process vents from batch unit operations associated with the use 

of an organic HAP to make or modify the product are less than 

11,800 kg per year, only the records in paragraphs (e)(1)(i) and 

(ii) of this section are required.

(2) Process vents from continuous unit operations. The 

owner or operator of an affected source that uses nonepoxide 

organic HAP to make or modify the product in continuous unit 

operations shall keep records regarding the measurements and 

calculations performed to determine the TRE index value of each 

process vent stream. The owner or operator of Group 1 continuous 
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process vents that are subject to the control requirements of 

§63.1425(c)(3) is not required to keep these records.

(f) Records for Group 2 process vents that are associated 

with the use of nonepoxide organic HAP to make or modify the 

product. The following records shall be maintained for PMPUs 

with a Group 2 combination of batch process vents and/or one or 

more Group 2 continuous process vents.

(1) Process vents from batch unit operations—emission 

records. The owner or operator shall maintain records of the 

combined total annual nonepoxide organic HAP emissions from 

process vents associated with the use of nonepoxide organic HAP 

to make or modify the product for each PMPU where the 

combination of these process vents is classified as Group 2.

(2) Process vents from continuous unit operations—

monitoring records for vents with TRE between 1.0 and 4.0. The 

owner or operator using a recovery device or other means to 

achieve and maintain a TRE index value greater than 1.0 but less 

than 4.0 as specified in the HON process vent requirements in 

§63.113(a)(3) or §63.113(d) shall keep the following records 

readily accessible:

(i) Continuous records of the equipment operating 

parameters specified to be monitored under §63.114(b) and listed 

in Table 5 of this subpart or specified by the Administrator in 

accordance with §63.114(c) and §63.117(e); and
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(ii) Records of the daily average value of each 

continuously monitored parameter for each operating day 

determined according to the procedures specified in §63.152(f). 

If carbon adsorber regeneration stream flow and carbon bed 

regeneration temperature are monitored, the records specified in 

Table 5 of this subpart shall be kept instead of the daily 

averages.

(3) Process vents from continuous unit operations—records 

related to process changes. The owner or operator subject to the 

provisions of this subpart who has elected to demonstrate 

compliance with the TRE index value greater than 4.0 under 

§63.113(e) or greater than 1.0 under §63.113(a)(3) or §63.113(d) 

shall keep readily accessible records of:

(i) Any process changes as defined in §63.115(e); and

(ii) Any recalculation of the TRE index value pursuant to 

§63.115(e).

(4) Process vents from continuous unit operations—records 

for vents with a flow rate less than 0.005 standard cubic meter 

per minute. The owner or operator who elects to comply by 

maintaining a flow rate less than 0.005 standard cubic meter per 

minute under §63.113(f), shall keep readily accessible records 

of:

(i) Any process changes as defined in §63.115(e) that 

increase the process vent stream flow rate;
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(ii) Any recalculation or measurement of the flow rate 

pursuant to §63.115(e); and

(iii) If the flow rate increases to 0.005 standard cubic 

meter per minute or greater as a result of the process change, 

the TRE determination performed according to the procedures of 

§63.115(d).

(5) Process vents from continuous unit operations—records 

for vents with an organic HAP concentration less than 50 parts 

per million. The owner or operator who elects to comply by 

maintaining an organic HAP concentration less than 50 parts per 

million by volume organic HAP concentration under §63.113(g) 

shall keep readily accessible records of:

(i) Any process changes as defined in §63.115(e) that 

increase the organic HAP concentration of the process vent 

stream;

(ii) Any recalculation or measurement of the concentration 

pursuant to §63.115(e); and

(iii) If the organic HAP concentration increases to 50 

parts per million by volume or greater as a result of the 

process change, the TRE determination performed according to the 

procedures of §63.115(d).

(g) Notification of Compliance Status. The owner or 

operator of an affected source shall submit the information 

specified in paragraphs (g)(1) through (3) of this section, as 
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appropriate, as part of the Notification of Compliance Status 

specified in §63.1439(e)(5).

(1) For the owner or operator complying with the process 

vent control requirements in §63.1425(b), (c)(1), (c)(3), or 

(d), the information specified in paragraph (b) of this section 

related to the compliance demonstration, and the information 

specified in paragraph (c) of this section related to the 

establishment of parameter monitoring levels,

(2) For each PMPU where the combination of process vents 

from batch unit operations that are associated with the use of 

nonepoxide organic HAP to make or modify the product is Group 2, 

the information related to the group determination specified in 

paragraph (e)(1) of this section.

(3) For each process vent from a continuous unit operation 

that is associated with the use of nonepoxide organic HAP to 

make or modify the product that is Group 2, the information 

related to the group determination specified in paragraph (e)(2) 

of this section.

(h) Periodic Reports. The owner or operator of an affected 

source shall submit Periodic Reports of the recorded information 

specified in paragraphs (h)(1) through (6) of this section, as 

appropriate, according to the schedule for submitting Periodic 

Reports in §63.1439(e)(6)(i).
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(1) Reports of daily average values of monitored parameters 

for all operating days when the daily average values recorded 

under paragraph (d)(2) of this section were above the maximum, 

or below the minimum, level established in the Notification of 

Compliance Status or operating permit.

(2) Reports of the duration of periods when monitoring data 

are not collected for each excursion caused by insufficient 

monitoring data as defined in §63.1438(f)(1)(iv), (f)(2)(i)(B), 

or (f)(3)(ii).

(3) Reports of the times and durations of all periods 

recorded under paragraph (d)(3) of this section when the process 

vent stream is diverted from the combustion, recovery, or 

recapture device through a bypass line.

(4) Reports of all periods recorded under paragraph (d)(4) 

of this section in which the seal mechanism is broken, the 

bypass line valve position has changed, or the key to unlock the 

bypass line valve was checked out.

(5) Reports of the times and durations of all periods 

recorded under paragraph (d)(1)(i) of this section in which all 

pilot flames of a flare were absent.

(6) Reports of all carbon bed regeneration cycles during

which the parameters recorded under paragraph (d)(1)(ii) of this 

section were above the maximum, or below the minimum, levels 
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established in the Notification of Compliance Status or 

operating permit.

(i) Reports of process changes. Whenever a process change, 

as defined in §63.1420(g)(3), is made that causes a Group 2 

combination of batch process vents at a PMPU that are associated 

with the use of nonepoxide organic HAP to make or modify the 

product to become Group 1, the owner or operator shall submit a 

report within 180 days after the process change is made or the 

information regarding the process change is known to the owner 

or operator. This report may be included in the next Periodic 

Report or in a separate submittal to the Administrator, as 

specified in §63.1439(e)(6)(iii)(D)(1). A description of the 

process change shall be submitted with the report.

(j) Reporting requirements for Group 2 continuous process 

vents. (1) Whenever a process change, as defined in 

§63.1420(g)(3), is made that causes a Group 2 continuous process 

vent with a TRE greater than 4.0 to become a Group 2 continuous 

process vent with a TRE less than 4.0, the owner or operator 

shall submit a report within 180 calendar days after the process 

change is made or the information regarding the process change 

is known, unless the flow rate is less than 0.005 standard cubic 

meters per minute. The report may be submitted as part of the 

next periodic report. The report shall include:

(i) A description of the process change;
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(ii) The results of the recalculation of the TRE index 

value required under §63.1428(h)(2), and recorded under 

paragraph (f)(3) of this section; and

(iii) A statement that the owner or operator will comply 

with the process vent monitoring requirements specified in 

§63.1429, as appropriate.

(2) Whenever a process change, as defined in 

§63.1420(g)(3), is made that causes a Group 2 continuous process 

vent with a flow rate less than 0.005 standard cubic meters per 

minute to become a Group 2 continuous process vent with a flow 

rate of 0.005 standard cubic meters per minute or greater, the 

owner or operator shall submit a report within 180 calendar days 

after the process change is made or the information regarding 

the process change is known, unless the organic HAP 

concentration is less than 50 ppmv. The report may be submitted 

as part of the next periodic report. The report shall include:

(i) A description of the process change;

(ii) The results of the calculation of the TRE index value 

required under §63.1428(h)(2), and recorded under paragraph 

(f)(3) of this section; and

(iii) A statement that the owner or operator will comply 

with the process vent monitoring requirements specified in 

§63.1429, as appropriate.
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(3) Whenever a process change, as defined in 

§63.1420(g)(3), is made that causes a Group 2 continuous process 

vent with an organic HAP concentration less than 50 ppmv to 

become a Group 2 continuous process vent with an organic HAP 

concentration of 50 ppmv or greater and a TRE index value less 

than 4.0, the owner or operator shall submit a report within 180 

calendar days after the process change is made or the 

information regarding the process change is known, unless the 

flow rate is less than 0.005 standard cubic meters per minute. 

The report may be submitted as part of the next periodic report. 

The report shall include:

(i) A description of the process change;

(ii) The results of the calculation of the TRE index value 

required under §63.1428(h)(2), and recorded under paragraph 

(f)(3) of this section; and

(iii) A statement that the owner or operator will comply 

with the process vent monitoring requirements specified in 

§63.1429, as appropriate.

(k) Alternative requests. If an owner or operator uses a 

combustion, recovery, or recapture device other than those 

specified in the process vent monitoring requirements in 

§63.1429(a)(1) through (7) and listed in Table 5 of this 

subpart; requests approval to monitor a parameter other than 

those specified in §63.1429(a)(1) through (7) and listed in 
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Table 5 of this subpart; or uses ECO and requests to monitor a 

parameter other than those listed in §63.1427(i)(1)(i) through 

(iii), as allowed under §63.1427(i)(1)(iv), the owner or 

operator shall submit a description of planned reporting and 

recordkeeping procedures, as specified in §63.1439(f)(3), as 

part of the Precompliance Report as required under 

§63.1439(e)(4), or to the Administrator as a separate submittal. 

The Administrator will specify appropriate reporting and 

recordkeeping requirements as part of the review of the 

Precompliance Report.

§63.1431 Process vent annual epoxides emission factor plan 

requirements.

(a) Applicability of emission factor plan requirements. An 

owner or operator electing to comply with an annual epoxide 

emission factor limitation in §63.1425(b)(1)(iii) or (b)(2)(iv) 

shall develop and implement an epoxides emission factor plan in 

accordance with the provisions of this section.

(b) Emission factor plan requirements. The owner or 

operator shall develop an epoxides emission factor plan.

(1) If epoxide emissions are maintained below the epoxide 

emission factor limitation through the use of a combustion, 

recovery, or recapture device (without extended cookout), the 

owner or operator shall develop and implement the plan in 

accordance with paragraph (c) of this section.
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(2) If epoxide emissions are maintained below the epoxide 

emission factor limitation through the use of extended cookout 

(without a combustion, recovery, or recapture device), the owner 

or operator shall develop and implement the plan in accordance 

with paragraph (d) of this section.

(3) If epoxide emissions are maintained below the epoxide 

emission factor limitation through the use of extended cookout 

in conjunction with a combustion, recovery, or recapture device, 

the owner or operator shall develop and implement the plan in 

accordance with paragraph (e) of this section.

(c) Compliance with epoxide emission factor limitation 

using a combustion, recovery, or recapture device. (1) The owner 

or operator shall notify the Agency of the intent to use a 

combustion, recovery, or recapture device to comply with the 

epoxide emission factor limitation in §63.1425(b)(1)(iii) or 

(b)(2)(iv). The owner or operator shall prepare an estimate of 

the annual epoxide emissions and the actual production rate in 

accordance with paragraphs (c)(1)(i) through (iv) of this 

section. This notification and emission estimate shall be 

submitted in the Precompliance Report as specified in 

§63.1439(e)(4), or in the operating permit application, as 

allowed in §63.1439(e)(8).

(i) Annual uncontrolled epoxide emissions. These emission 

estimates shall be determined in accordance with the batch 
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process vent group determination procedures in the NESHAP for 

Group I Polymers and Resins (40 CFR part 63, subpart U, 

§63.488(b)) and shall be based on anticipated production.

(ii) A description of the combustion, recovery, or 

recapture device, along with the expected percent efficiency.

(iii) Annual emissions after the combustion, recovery, or 

recapture device. The expected annual emissions after control 

shall be determined using Equation 15.

Where:

AEcontrol = Annual epoxide emissions after control, kg/yr.

AEuncontrolled = Annual uncontrolled epoxide emissions, 

determined in accordance with paragraph (c)(1)(i) of this 

section, kg/yr.

R = Expected control efficiency of the combustion, 

recovery, or recapture device, percent, as determined in 

§63.1426(c).

(iv) The actual annual production rate means the annual 

mass of polyether polyol product produced from the applicable 

PMPU. This production rate shall be for the same annual time 

period as the annual emission estimate as calculated in 

accordance with paragraph (c)(1)(iii) of this section.
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(2) The owner or operator shall conduct a performance test 

in accordance with §63.1426(c) to determine the epoxide control 

efficiency of the combustion, recovery, or recapture device. The 

owner or operator shall then recalculate the annual epoxide 

emissions after control using Equation 15, except that the 

control efficiency, R, shall be the measured control efficiency. 

This information shall be submitted as part of the Notification 

of Compliance Status, as provided in §63.1439(e)(5).

(3) The owner or operator shall comply with the process 

vent monitoring provisions in §63.1429.

(4) The owner or operator shall comply with the process 

vent recordkeeping requirements in paragraphs §63.1430(b) 

through (d), and the process vent reporting requirements in 

§63.1430(g)(1) and (h).

(d) Compliance with epoxide emission factor limitation 

using extended cookout. (1) The owner or operator shall notify 

the Agency of the intent to use extended cookout to comply with 

the epoxide emission factor limitation in §63.1425(b)(1)(iii) or 

(b)(2)(iv). The owner or operator shall prepare an estimate of 

the annual epoxide emissions after the extended cookout. This 

notification and emission estimate shall be submitted in the 

Precompliance Report as specified in §63.1439(e)(4), or in the 

operating permit application, as allowed in §63.1439(e)(8).
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(2) The owner or operator shall determine the annual 

epoxide emissions in accordance with §63.1427(d), based on 

anticipated production. This information shall be submitted as 

part of the Notification of Compliance Status, as provided in 

§63.1439(e)(5).

(3) The owner or operator shall comply with the ECO 

monitoring provisions in §63.1427(i).

(4) The owner or operator shall comply with the process 

vent recordkeeping and reporting requirements in §63.1430.

(e) Compliance with the epoxide emission factor limitation 

through the use of extended cookout in conjunction with one or 

more combustion, recovery, and/or recapture device. (1) The 

owner or operator shall notify the Agency of the intent to use 

extended cookout in conjunction with one or more combustion, 

recovery, and/or recapture device to comply with the annual 

epoxide emission factor limitation in §63.1425(b)(1)(iii) or 

(b)(2)(iv). The owner or operator shall prepare an estimate of 

the annual epoxide emissions after control. This notification 

and emission estimate shall be submitted in the Precompliance 

Report as specified in §63.1439(e)(4), or in the operating 

permit application, as allowed under §63.1439(e)(8).

(2) The owner or operator shall determine the annual 

epoxide emissions after control. This information shall be 
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submitted as part of the Notification of Compliance Status, as 

provided in §63.1439(e)(5).

(3) The owner or operator shall comply with the ECO 

monitoring provisions in §63.1427(i).

(4) The owner or operator shall comply with the ECO 

recordkeeping and reporting requirements in §63.1427(j) and (k).

(f) Compliance with epoxide emission factor limitation 

without using extended cookout or a combustion, recovery, or 

recapture device. (1) The owner or operator shall notify the 

Agency of the intent to comply with the epoxide emission factor 

limitation in §63.1425(b)(1)(iii) or (b)(2)(iv) without the use 

of ECO or a combustion, recovery, or recapture device. The owner 

or operator shall prepare an estimate of the annual epoxide 

emissions. This notification and emission estimate shall be 

submitted in the Precompliance Report as specified in 

§63.1439(e)(4), or in the operating permit application, as 

allowed in §63.1439(e)(8).

(2) Each year after the compliance date, the owner or 

operator shall calculate the epoxides emission factor for the 

previous year. This information shall be submitted in the second 

Periodic Report submitted each year, as specified in 

§63.1439(e)(6).

§63.1432 Storage vessel provisions.
Page 159 of 262

(a) For each storage vessel located at an affected source, 

the owner or operator shall comply with the HON storage vessel 

requirements of §§63.119 through 63.123 and the HON leak 

inspection provisions in §63.148, with the differences noted in 

paragraphs (b) through (p) of this section, for the purposes of 

this subpart.

(b) When the term “storage vessel” is used in the HON

storage vessel requirements in §§63.119 through 63.123, the 

definition of this term in §63.1423 shall apply for the purposes 

of this subpart.

(c) When the term “Group 1 storage vessel” is used in the 

HON storage vessel requirements in §§63.119 through 63.123, the 

definition of this term in §63.1423 shall apply for the purposes 

of this subpart.

(d) When the term “Group 2 storage vessel” is used in the 

HON storage vessel requirements in §§63.119 through 63.123, the 

definition of this term in §63.1423 shall apply for the purposes 

of this subpart.

(e) When the HON storage vessel requirements in §63.119 

refer to “December 31, 1992,” the phrase “September 4, 1997” 

shall apply instead, for the purposes of this subpart.

(f) When the HON storage vessel requirements in §63.119 

refer to “April 22, 1994,” the phrase “June 1, 1999,” shall 

apply instead, for the purposes of this subpart.
Page 160 of 262

(g) The owner or operator of an affected source shall 

comply with this paragraph instead of §63.120(d)(1)(ii) for the 

purposes of this subpart. If the combustion, recovery, or 

recapture device used to comply with §63.119(e) is also used to 

comply with any of the requirements found in §§63.1425 through 

63.1431 and/or §63.1433, the performance test required in or 

accepted by §§63.1425 through 63.1431 and/or §63.1433 is 

acceptable for demonstrating compliance with the HON storage 

vessel requirements in §63.119(e), for the purposes of this 

subpart. The owner or operator will not be required to prepare a 

design evaluation for the combustion, recovery, or recapture 

device as described in §63.120(d)(1)(i), if the performance test 

meets the criteria specified in paragraphs (g)(1) and (2) of 

this section.

(1) The performance test demonstrates that the combustion, 

recovery, or recapture device achieves greater than or equal to 

the required control efficiency specified in the HON storage 

vessel requirements in §63.119(e)(1) or (2), as applicable; and

(2) The performance test is submitted as part of the 

Notification of Compliance Status required by §63.1439(e)(5).

(h) When the HON storage vessel requirements in 

§§63.120(d)(3)(i), 63.120(d)(5), and 63.122(g)(2) use the term 

“range,” the term “level” shall apply instead for the purposes 

of this subpart.
Page 161 of 262

(i) For purposes of this subpart, the monitoring plan 

required by the HON storage vessel requirements in §63.120(d)(2) 

shall specify for which combustion, recovery, or recapture 

device the owner or operator has selected to follow the 

procedures for continuous monitoring specified in §63.1438. For 

the combustion, recovery, or recapture device(s) for which the 

owner or operator has selected not to follow the procedures for 

continuous monitoring specified in §63.1438, the monitoring plan 

shall include a description of the parameter(s) to be monitored 

to ensure that the combustion, recovery, or recapture device is 

being properly operated and maintained, an explanation of the 

criteria used for selection of that parameter(s), and the 

frequency with which monitoring will be performed (e.g., when 

the liquid level in the storage vessel is being raised), as 

specified in §63.120(d)(2)(i).

(j) For purposes of this subpart, the monitoring plan 

required by §63.122(b) shall be included in the Notification of 

Compliance Status required by §63.1439(e)(5).

(k) When the HON Notification of Compliance Status 

requirements contained in §63.152(b) are referred to in 

§§63.120, 63.122, and 63.123, the Notification of Compliance 

Status requirements contained in §63.1439(e)(5) shall apply for 

the purposes of this subpart.
Page 162 of 262

(l) When the HON Periodic Report requirements contained in 

§63.152(c) are referred to in §§63.120 and 63.122, the Periodic 

Report requirements contained in §63.1439(e)(6) shall apply for 

the purposes of this subpart.

(m) When other reports as required in §63.152(d) are 

referred to in §63.122, the reporting requirements contained in 

§63.1439(e)(7) shall apply for the purposes of this subpart.

(n) When the HON Initial Notification requirements 

contained in §63.151(b) are referred to in §63.119 through 

§63.123, the owner or operator shall comply with the Initial 

Notification requirements contained in §63.1439(e)(3), for the 

purposes of this subpart.

(o) When the determination of equivalence criteria in 

§63.102(b) are referred to in the HON storage vessel 

requirements in §63.121(a), the General Provisions' alternative 

nonopacity emission provisions in §63.6(g) shall apply for the 

purposes of this subpart.

(p) The compliance date for storage vessels at affected 

sources subject to the provisions of this section is specified 

in §63.1422.

(q) In addition to the records required by §63.123, the 

owner or operator of each storage vessel that is complying with 

§63.119(e) and that has an applicable monitoring plan in 

accordance with §63.120(d)(2) that does not specify continuous 
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monitoring, shall maintain records of all times when the storage 

tank is being filled (i.e., when the liquid level in the storage 

vessel is being raised). These records shall consist of 

documentation of the time when each filling period begins and 

ends.

§63.1433 Wastewater provisions.

(a) Process wastewater. Except as specified in paragraph 

(c) of this section, the owner or operator of each affected 

source shall comply with the HON wastewater requirements in 

§§63.132 through 63.147 for each process wastewater stream 

originating at an affected source, with the HON leak inspection 

requirements in §63.148, and with the HON requirements in 

§63.149 for equipment that is subject to §63.149, with the 

differences noted in paragraphs (a)(1) through (20) of this 

section. Further, the owner or operator of each affected source 

shall comply with the requirements of §63.105(a) for maintenance 

wastewater, as specified in paragraph (b) of this section.

(1) Owners and operators of affected sources are not 

required to comply with the HON new source wastewater 

requirements in §63.132(b)(1) and §63.132(d) for the purposes of 

this subpart. Owners or operators of all new affected sources, 

as defined in this subpart, shall comply with the HON 

requirements for existing sources in §§63.132 through 63.149, 
Page 164 of 262

with the exceptions noted in paragraphs (a)(2) through (20) of 

this section.

(2) The provisions of paragraphs (a)(2)(i), (ii), and 

(a)(10)(iii) of this section clarify the organic HAP that an 

owner or operator shall consider when complying with the 

requirements of §§63.132 through 63.149.

(i) Owners and operators are exempt from all requirements 

in §§63.132 through 63.149 that pertain solely and exclusively 

to organic HAP listed on Table 8 of 40 CFR part 63, subpart G.

(ii) When the HON requirements in §§63.132 through 63.149 

refer to Table 9 compounds, the owner or operator is only 

required to consider compounds that meet the definition of 

organic HAP in §63.1423 and that are listed in Table 9 of 40 CFR 

part 63, subpart G, for the purposes of this subpart.

(iii) When §§63.132 through 63.149 refer to compounds in 

Table 36 of 40 CFR part 63, subpart G, or compounds in List 1 or 

List 2 of Table 36 of 40 CFR part 63, subpart G, the owner or 

operator is only required to consider compounds that meet the 

definition of organic HAP in §63.1423 and that are listed on 

Table 36 of 40 CFR part 63, subpart G, for the purposes of this 

subpart.

(3) When the determination of equivalence criteria in 

§63.102(b) is referred to in §§63.132, 63.133, and 63.137, the 

General Provisions' alternative nonopacity emission standard 
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provisions in §63.6(g) shall apply for the purposes of this 

subpart.

(4) When the HON storage vessel requirements contained in 

§§63.119 through 63.123 are referred to in §§63.132 through 

63.148, the HON storage vessel requirements in §§63.119 through 

63.123 are applicable, with the exception of the differences 

referred to in the storage vessel requirements in §63.1432, for 

the purposes of this subpart.

(5) When the HON process wastewater reporting requirements 

in §63.146(a) require the submission of a request for approval 

to monitor alternative parameters according to the procedures 

specified in §63.151(f) or (g), the owner or operator requesting 

to monitor alternative parameters shall follow the procedures 

specified in §63.1439(f) for the purposes of this subpart.

(6) When the HON process wastewater recordkeeping 

requirements in §63.147(d) require the owner or operator to keep 

records of the daily average value of each continuously 

monitored parameter for each operating day as specified in the 

HON recordkeeping provisions in §63.152(f), the owner or 

operator shall instead keep records of the daily average value 

of each continuously monitored parameter as specified in 

§63.1439(d), for the purposes of this subpart.
Page 166 of 262

(7) When §§63.132 through 63.149 refer to an “existing 

source,” the term existing affected source, as defined in 

§63.1420(a)(2), shall apply for the purposes of this subpart.

(8) When the HON requirements in §§63.132 through 63.149 

refer to a “new source,” the term new affected source, as 

defined in §63.1420(a)(3), shall apply for the purposes of this 

subpart.

(9) When the HON process wastewater provisions in §63.132 

(a) and (b) refer to the “applicable dates specified in §63.100 

of subpart F of this part,” the applicable compliance dates 

specified in §63.1422 shall apply, for the purposes of this 

subpart.

(10) Whenever the HON process wastewater provisions in 

§§63.132 through 63.147 refer to a Group 1 wastewater stream or 

a Group 2 wastewater stream, the definitions of these terms 

contained in §63.1423 shall apply, for the purposes of this 

subpart.

(11) When the HON control requirements for certain liquid 

streams in open systems, in §63.149(d), refer to “§63.100(f) of 

subpart F,” the phrase “§63.1420(c),” shall apply for the 

purposes of this subpart. In addition, where §63.149(d) states 

“and the item of equipment is not otherwise exempt from controls 

by the provisions of subparts A, F, G, or H of this part,” the 

phrase “and the item of equipment is not otherwise exempt from 
Page 167 of 262

controls by the provisions of subparts A, F, G, H, or PPP of 

this part,” shall apply for the purposes of this subpart.

(12) When the HON control requirements for certain liquid 

streams in open systems, in §63.149(e) (1) and (2), refer to “a 

chemical manufacturing process unit subject to the new source 

requirements of 40 CFR 63.100(l) (1) or (2),” the phrase “a new 

affected source as described in §63.1420(a)(4),” shall apply for 

the purposes of this subpart.

(13) When the HON Notification of Compliance Status 

requirements contained in §63.152(b) are referred to in the HON 

process wastewater provisions in §63.138 or §63.146, the 

Notification of Compliance Status requirements contained in 

§63.1439(e)(5) shall apply for the purposes of this subpart. In 

addition, when the HON process wastewater provisions in §63.138 

or §63.146 require that information be reported according to 

§63.152(b) in the HON Notification of Compliance Status, owners 

or operators of affected sources shall report the specified 

information in the Notification of Compliance Status required by 

§63.1439(e)(5), for the purposes of this subpart.

(14) When the HON Periodic Report requirements contained in 

§63.152(c) are referred to in the HON process wastewater 

provisions in §63.146, the Periodic Report requirements 

contained in §63.1439(e)(6) shall apply for the purposes of this 

subpart. In addition, when §63.146 requires that information be 
Page 168 of 262

reported in the HON Periodic Reports required in §63.152(c), 

owners or operators of affected sources shall report the 

specified information in the Periodic Reports required in 

§63.1439(e)(6), for the purposes of this subpart.

(15) When the term “range” is used in the HON requirements 

in §§63.132 through 63.149, the term “level” shall be used 

instead, for the purposes of this subpart. This level shall be 

determined using the procedures specified in parameter 

monitoring procedures in §63.1438.

(16) When the HON process wastewater monitoring and 

inspection provisions in §63.143(f) specify that the owner or 

operator shall establish the range that indicates proper 

operation of the treatment process or control technique, the 

owner or operator shall instead comply with the requirements 

§63.1438 (c) or (d) for establishing parameter level 

maximums/minimums, for the purposes of this subpart.

(17) When the HON process wastewater provisions in 

§63.146(b) (7) and (8) require that “the information on 

parameter ranges specified in §63.152(b)(2)” be reported in the 

HON Notification of Compliance Status, owners and operators of 

affected sources are instead required to report the information 

on parameter levels in the Notification of Compliance Status as 

specified in §63.1439(e)(5)(ii), for the purposes of this 

subpart.
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(18) For the purposes of this subpart, the owner or 

operator is not required to comply with the HON process 

wastewater emission reduction provisions in §63.138(g).

(19) When the provisions of HON process wastewater 

provisions in §63.139(c)(1)(ii), §63.145(d)(4), or §63.145(i)(2) 

specify that Method 18, 40 CFR part 60, appendix A shall be 

used, Method 18 or Method 25A, 40 CFR part 60, appendix A may be 

used for the purposes of this subpart. The use of Method 25A, 40 

CFR part 60, appendix A shall comply with paragraphs (a)(19) (i) 

and (ii) of this section.

(i) The organic HAP used as the calibration gas for Method 

25A, 40 CFR part 60, appendix A shall be the single organic HAP 

representing the largest percent by volume of the emissions.

(ii) The use of Method 25A, 40 CFR part 60, appendix A is 

acceptable if the response from the high-level calibration gas 

is at least 20 times the standard deviation of the response from 

the zero calibration gas when the instrument is zeroed on the 

most sensitive scale.

(20) The owner or operator of a facility which receives a 

Group 1 wastewater stream, or a residual removed from a Group 1 

wastewater stream, for treatment pursuant to the HON provisions 

in §63.132(g) is subject to the requirements of §63.132(g), with 

the differences identified in this section, and is not subject 
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to the NESHAP from off-site waste and recovery operations in 40 

CFR part 63, subpart DD, with respect to the received material.

(b) Maintenance wastewater. The owner or operator of each 

affected source shall comply with the HON maintenance wastewater 

requirements in §63.105, with the exceptions noted in paragraphs 

(b) (1), (2), and (3) of this section.

(1) When the HON maintenance wastewater provisions in 

§63.105(a) refer to “organic HAPs listed in Table 9 of subpart G 

of this part,” the owner or operator is only required to 

consider compounds that meet the definition of organic HAP in 

§63.1423 and that are listed in Table 9 of 40 CFR part 63, 

subpart G, for the purposes of this subpart.

(2) When the term “maintenance wastewater” is used in the 

HON maintenance wastewater provisions in §63.105, the definition 

of “maintenance wastewater” in §63.1423 shall apply, for the 

purposes of this subpart.

(3) When the term “wastewater” is used in the HON 

maintenance wastewater provisions in §63.105, the definition of 

“wastewater” in §63.1423 shall apply, for the purposes of this 

subpart.

(c) Compliance date. The compliance date for the affected 

source subject to the provisions of this section is specified in 

§63.1422.

§63.1434 Equipment leak provisions.
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(a) The owner or operator of each affected source shall 

comply with the HON equipment leak requirements in 40 CFR part 

63, subpart H for all equipment in organic HAP service, except 

§63.165 and as specified in paragraphs (b) through (gh) of this 

section.

(b) The compliance date for the equipment leak provisions 

in this section is provided in §63.1422(d).

(c) Requirements for pressure relief devices. Except as 

specified in paragraph (c)(4) of this section, the owner or 

operator must comply with the operating and pressure release 

requirements specified in paragraphs (c)(1) and (2) of this 

section for pressure relief devices in organic HAP gas or vapor 

service. Except as specified in paragraph (c)(4) of this 

section, the owner or operator must also comply with the 

pressure release management requirements specified in paragraph 

(c)(3) of this section for all pressure relief devices in 

organic HAP service.

(1) Operating requirements. Except during a pressure 

release event, operate each pressure relief device in organic 

HAP gas or vapor service with an instrument reading of less than 

500 ppm above background as detected by Method 21 of 40 CFR part 

60, appendix A.
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(2) Pressure release requirements. For pressure relief 

devices in organic HAP gas or vapor service, comply with 

paragraph (c)(2)(i) or (ii) of this section, as applicable.

(i) If the pressure relief device does not consist of or 

include a rupture disk, conduct instrument monitoring, as 

detected by Method 21 of 40 CFR part 60, appendix A, no later 

than 5 calendar days after the pressure release to verify that 

the pressure relief device is operating with an instrument 

reading of less than 500 ppm above background, except as 

provided in §63.171.

(ii) If the pressure relief device consists of or includes 

a rupture disk, install a replacement disk as soon as 

practicable after a pressure release, but no later than 5 

calendar days after the pressure release, except as provided in 

§63.171.

(3) Pressure release management. Except as specified in 

paragraph (c)(4) of this section, pressure releases to the 

atmosphere from pressure relief devices in organic HAP service 

are prohibited, and the owner or operator must comply with the 

requirements specified in paragraphs (c)(3)(i) and (ii) of this 

section for all pressure relief devices in organic HAP service.

(i) For each pressure relief device in organic HAP service, 

the owner or operator must equip each pressure relief device 

with a device(s) or use a monitoring system that is capable of: 
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1) identifying the pressure release; 2) recording the time and 

duration of each pressure release; and 3) notifying operators 

immediately that a pressure release is occurring. The device or 

monitoring system may be either specific to the pressure relief 

device itself or may be associated with the process system or 

piping, sufficient to indicate a pressure release to the 

atmosphere. Examples of these types of devices and systems 

include, but are not limited to, a rupture disk indicator, 

magnetic sensor, motion detector on the pressure relief valve 

stem, flow monitor, or pressure monitor.

(ii) If any pressure relief device in organic HAP service 

releases to atmosphere as a result of a pressure release event, 

the owner or operator must calculate the quantity of organic HAP 

released during each pressure release event and report this 

quantity as required in §63.1439(e)(6)(ix). Calculations may be 

based on data from the pressure relief device monitoring alone 

or in combination with process parameter monitoring data and 

process knowledge.

(4) Pressure relief devices routed to a control device,

process, or drain system. If a pressure relief device in organic 

HAP service is designed and operated to route all pressure 

releases through a closed vent system to a control device, 

process, or drain system, the owner or operator is not required 

to comply with paragraphs (c)(1), (2), or (3) (if applicable) of 
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this section. Both the closed vent system and control device (if 

applicable) must meet the requirements of §63.172. The drain 

system (if applicable) must meet the requirements of 

§63.136.[Reserved]

(d) When the HON equipment leak Initial Notification 

requirements contained in §63.182(a)(1) and §63.182(b) are 

referred to in 40 CFR part 63, subpart H, the owner or operator 

shall comply with the Initial Notification requirements 

contained in §63.1439(e)(3), for the purposes of this subpart. 

The Initial Notification shall be submitted no later than June 

1, 2000 for existing sources, as stated in 

§63.1439(e)(3)(ii)(A).

(e) The HON equipment leak Notification of Compliance 

Status required by §63.182(a)(2) and §63.182(c) shall be 

submitted within 150 days (rather than 90 days) of the 

applicable compliance date specified in §63.1422 for the 

equipment leak provisions. The notification may be submitted as 

part of the Notification of Compliance Status required by 

§63.1439(e)(5).

(f) The Periodic Reports required by §63.182(a)(3) and 

§63.182(d) may be submitted as part of the Periodic Reports 

required by §63.1439(e)(6).

(g) If specific items of equipment, comprising part of a 

process unit subject to this subpart, are managed by different 
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administrative organizations (e.g., different companies, 

affiliates, departments, divisions, etc.), those items of 

equipment may be aggregated with any PMPU within the affected 

source for all purposes under subpart H, providing there is no 

delay in achieving the applicable compliance date.

(h) The phrase “the provisions of subparts F, I, or PPP of 

this part” shall apply instead of the phrase “the provisions of 

subparts F or I of this part,” and instead of the phrase “the 

provisions of subpart F or I of this part” throughout §§63.163 

and 63.168, for the purposes of this subpart. In addition, the 

phrase “subparts F, I, and PPP” shall apply instead of the 

phrase “subparts F and I” in §63.174(c)(2)(iii), for the 

purposes of this subpart.

§63.1435 Heat exchanger provisions.

(a) The owner or operator of each affected source shall 

comply with the requirements of §63.104 for heat exchange 

systems, with the exceptions noted in paragraphs (b) through (e) 

of this section.

(b) When the term “chemical manufacturing process unit” is 

used in §63.104, the term “polyether polyols manufacturing 

process unit” shall apply for the purposes of this subpart. 

Further, when the phrase “a chemical manufacturing process unit 

meeting the conditions of §63.100(b)(1) through (3) of this 

subpart, except for chemical manufacturing process units meeting 
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the condition specified in §63.100(c) of this subpart” is used 

in §63.104(a), the term “PMPU, except for PMPU meeting the 

conditions specified in §63.1420(b)” shall apply for the 

purposes of this subpart.

(c) When the HON heat exchange system requirements in 

§63.104(c)(3) specify the monitoring plan retention 

requirements, and when §63.104(f)(1) refers to the record 

retention requirements in §63.103(c)(1), the provisions of the 

general recordkeeping and reporting requirements in §63.1439(a) 

and the applicable provisions of the General Provisions in 40 

CFR part 63, subpart A, as specified in Table 1 of this subpart, 

shall apply for the purposes of this subpart.

(d) When the HON heat exchange system requirements in 

§63.104(f)(2) require information to be reported in the Periodic 

Reports required by the HON general reporting provisions in 

§63.152(c), the owner or operator shall instead report the 

information specified in §63.104(f)(2) in the Periodic Reports 

required by the general reporting requirements in 

§63.1439(e)(6), for the purposes of this subpart.

(e) When the HON heat exchange system requirements in 

§63.104 refer to Table 4 of 40 CFR part 63, subpart F or Table 9 

of 40 CFR part 63, subpart G, the owner or operator is only 

required to consider organic HAP listed in Table 4 of 40 CFR 

part 63, subpart F or 40 CFR part 63, Table 9 of subpart G that 
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are also listed on Table 4 of this subpart, for the purposes of 

this subpart.

§63.1436 [Reserved]

§63.1437 Additional requirements for performance testing.

(a) Performance testing shall be conducted in accordance 

with §63.7(a)(1), (a)(3), (d), (e)(1), (e)(2), (e)(4), (g), and 

(h), with the exceptions specified in paragraphs (a)(1) through 

(4) of this section and the additions specified in paragraph (b) 

of this section. Performance tests shall be conducted under such 

conditions as the Administrator specifies to the owner or 

operator based on representative performance of the affected 

source for the period being tested. Representative conditions 

exclude periods of startup and shutdown unless specified by the 

Administrator or an applicable subpart. The owner or operator 

may not conduct performance tests during periods of malfunction. 

The owner or operator must record the process information that 

is necessary to document operating conditions during the test 

and include in such record an explanation to support that such 

conditions represent normal operation. Upon request, the owner 

or operator shall make available to the Administrator such 

records as may be necessary to determine the conditions of 

performance tests.

(1) Performance tests shall be conducted according to the 

general provisions' performance testing requirements in 
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§63.7(e)(1) and (2), except that for all emission sources except 

process vents from batch unit operations, performance tests 

shall be conducted during maximum representative operating 

conditions for the process achievable during one of the time 

periods described in paragraph (a)(1)(i) of this section, 

without causing any of the situations described in paragraph 

(a)(1)(ii) or (iii) of this section to occur. For process vents 

from batch unit operations, performance tests shall be conducted 

either at absolute worst-case conditions or hypothetical worstcase conditions, as defined in §63.1426(c)(3)(i)(B), that are 

achievable during one of the time periods described in paragraph 

(a)(1)(i) of this section, without causing any of the situations 

described in paragraph (a)(1)(ii) or (iii) of this section to 

occur.

(i) The 6-month period that ends 2 months before the 

Notification of Compliance Status is due, according to 

§63.1439(e)(5); or the 6-month period that begins 3 months 

before the performance test and ends 3 months after the 

performance test.

(ii) Causing damage to equipment; necessitating that the 

owner or operator make a product that does not meet an existing 

specification for sale to a customer; or necessitating that the 

owner or operator make a product in excess of demand.
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(iii) Causing plant or testing personnel to be subject to 

unsafe conditions. Owners or operators that limit testing based 

on this paragraph shall maintain documentation that demonstrates 

the nature of the unsafe conditions and explains measures 

considered by the owner or operator to overcome these 

conditions. If requested, this documentation shall be provided 

to the Administrator.

(2) When the General Provisions' data analysis, 

recordkeeping, and reporting requirements in §63.7(g) refer to 

the Notification of Compliance Status requirements in §63.9(h), 

the Notification of Compliance Status requirements in 

§63.1439(e)(5) shall instead apply, for the purposes of this 

subpart.

(3) Because the General Provisions' site-specific test plan 

in §63.7(c)(3) is not required, the General Provisions' 

requirement for the Administrator to approve or deny sitespecific test plans, in §63.7(h)(4)(ii), is not applicable for 

the purposes of this subpart.

(4) The owner or operator of an affected source shall 

provide the Administrator at least 30 days prior notice of any 

performance test, except as specified under other subparts, to 

afford the Administrator the opportunity to have an observer 

present. If after 30 days notice for an initially scheduled 

performance test, there is a delay (due to operational problems, 
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etc.) in conducting the scheduled performance test, the owner or 

operator of an affected source shall notify the Administrator 

(or delegated State or local agency) as soon as possible of any 

delay in the original test date, either by providing at least 7 

days prior notice of the rescheduled test date of the 

performance test, or by arranging a rescheduled date with the 

Administrator (or delegated State or local agency) by mutual 

agreement.

(b) Data shall be reduced in accordance with the EPA 

approved methods specified in the applicable subpart or, if 

other test methods are used, the data and methods shall be 

validated according to the protocol in Method 301, 40 CFR part 

63, appendix A.

(c) Notwithstanding any other provision of this subpart, if 

an owner or operator of an affected source uses a flare to 

comply with any of the requirements of this subpart, the owner 

or operator shall comply with paragraphs (c)(1) through (3) of 

this section. The owner or operator is not required to conduct a 

performance test to determine percent emission reduction or 

outlet organic HAP or TOC concentration. If a compliance 

demonstration has been conducted previously for a flare, using 

the techniques specified in paragraphs (c)(1) through (3) of 

this section, that compliance demonstration may be used to 

satisfy the requirements of this paragraph if either no 
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deliberate process changes have been made since the compliance 

demonstration, or the results of the compliance demonstration 

reliably demonstrate compliance despite process changes.

(1) Conduct a visible emission test using the techniques 

specified in §63.11(b)(4) of the General Provisions;

(2) Determine the net heating value of the gas being 

combusted, using the techniques specified in §63.11(b)(6) of the 

General Provisions; and

(3) Determine the exit velocity using the techniques 

specified in either §63.11(b)(7)(i) (and §63.11(b)(7)(iii), 

where applicable) or §63.11(b)(8) of the General Provisions, as 

appropriate.

§63.1438 Parameter monitoring levels and excursions.

(a) Establishment of parameter monitoring levels. The owner 

or operator of a combustion, recovery, or recapture device that 

has one or more parameter monitoring level requirements 

specified under this subpart shall establish a maximum or 

minimum level for each measured parameter. If a performance test 

is required by this subpart for a combustion, recovery, or 

recapture device, the owner or operator shall use the procedures 

in either paragraph (b) or (c) of this section to establish the 

parameter monitoring level(s). If a performance test is not 

required by this subpart for a combustion, recovery, or 

recapture device, the owner or operator may use the procedures 
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in paragraph (b), (c), or (d) of this section to establish the 

parameter monitoring levels. When using the procedures specified 

in paragraph (c) or (d) of this section, the owner or operator 

shall submit the information specified in §63.1439(e)(4)(viii) 

for review and approval, as part of the Precompliance Report.

(1) The owner or operator shall operate combustion, 

recovery, and recapture devices such that the daily average 

value of monitored parameters remains at or above the minimum 

established level, or remains at or below the maximum 

established level, except as otherwise provided in this subpart.

(2) As specified in §63.1439(e)(5)(ii), all established 

levels, along with their supporting documentation and the 

definition of an operating day, shall be submitted as part of 

the Notification of Compliance Status.

(3) Nothing in this section shall be construed to allow a 

monitoring parameter excursion caused by an activity that 

violates other applicable provisions of 40 CFR part 63, subparts 

A, F, G, or H.

(b) Establishment of parameter monitoring levels based 

exclusively on performance tests. In cases where a performance 

test is required by this subpart, or the owner or operator of 

the affected source elects to do a performance test in 

accordance with the provisions of this subpart, and an owner or 

operator elects to establish a parameter monitoring level for a 
Page 183 of 262

combustion, recovery, or recapture device based exclusively on 

parameter values measured during the performance test, the owner 

or operator of the affected source shall comply with the 

procedures in paragraph (b)(1) or (2) of this section, as 

applicable.

(1) Process vents from continuous unit operations. During 

initial compliance testing, the appropriate parameter shall be 

continuously monitored during the required 1-hour runs for 

process vents from continuous unit operations. The monitoring 

level(s) shall then be established as the average of the maximum 

(or minimum) point values from the three 1-hour test runs. The 

average of the maximum values shall be used when establishing a 

maximum level, and the average of the minimum values shall be 

used when establishing a minimum level.

(2) Process vents from batch unit operations. For process 

vents from batch unit operations, during initial compliance 

testing, the appropriate parameter shall be monitored 

continuously during the entire test period. The monitoring 

level(s) shall be those established during from the compliance 

test.

(c) Establishment of parameter monitoring levels based on 

performance tests, supplemented by engineering assessments 

and/or manufacturer's recommendations. Parameter monitoring 

levels established under this paragraph shall be based on the 
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parameter values measured during the performance test 

supplemented by engineering assessments and/or manufacturer's 

recommendations. Performance testing is not required to be 

conducted over the entire range of expected parameter values. 

The information specified in paragraphs (c)(1) and (2) of this 

section shall be provided in the Notification of Compliance 

Status.

(1) The specific level of the monitored parameter(s) for 

each emission point.

(2) The rationale for the specific level for each parameter 

for each emission point, including any data and calculations 

used to develop the level and a description of why the level 

indicates proper operation of the combustion, recovery, or 

recapture device.

(d) Establishment of parameter monitoring based on 

engineering assessments and/or manufacturer's recommendations. 

If a performance test is not required by this subpart for a 

combustion, recovery, or recapture device, the maximum or 

minimum level may be based solely on engineering assessments 

and/or manufacturers' recommendations. As required in paragraph 

(a)(2) of this section, the determined level and all supporting 

documentation shall be provided in the Notification of 

Compliance Status.
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(e) Monitoring violations. (1) With the exception of 

excursions excused in accordance with paragraph (g) of this 

section, eEach excursion, as defined in paragraphs (f)(1)(i), 

(f)(2)(i)(A), (f)(2)(ii), (f)(3)(i), and (f)(4) of this section, 

constitutes a violation of the provisions of this subpart in 

accordance with paragraph (e)(1)(i), (ii), or (iii) of this 

section.

(i) For each condenser, each excursion constitutes a 

violation of the emission limit.

(ii) For each recovery or recapture device other than a 

condenser, where an organic monitoring device is used to monitor 

concentration, each excursion constitutes a violation of the 

emission limit.

(iii) For each combustion, recovery, or recapture device 

other than a condenser, each excursion constitutes a violation 

of the operating limit.

(2) With the exception of excursions excused in accordance 

with paragraph (g) of this section, eEach excursion, as defined 

in paragraphs (f)(1)(ii), (f)(1)(iii), (f)(2)(i)(B), and 

(f)(3)(ii) of this section constitutes a violation of the 

operating limit.

(f) Parameter monitoring excursion definitions. Parameter 

monitoring excursions are defined in paragraphs (f)(1) through 

(3) of this section.
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(1) With respect to storage vessels (where the applicable 

monitoring plan specifies continuous monitoring), process vents 

from continuous unit operations using combustion, recovery, or 

recapture devices for purposes of compliance, and for process 

wastewater streams, an excursion means any of the three cases 

listed in paragraphs (f)(1)(i) through (iii) of this section.

(i) The daily average value of one or more monitored 

parameters is above the maximum level or below the minimum level 

established for the given parameters.

(ii) The period of combustion, recovery, or recapture 

device operation, with the exception noted in paragraph 

(f)(1)(v) of this section, is 4 hours or greater in an operating 

day and monitoring data are insufficient, as defined in 

paragraph (f)(1)(iv) of this section, to constitute a valid hour 

of data for at least 75 percent of the operating hours.

(iii) The period of combustion, recovery, or recapture 

device operation, with the exception noted in paragraph 

(f)(1)(v) of this section, is less than 4 hours in an operating 

day and more than 2 of the hours during the period of operation 

do not constitute a valid hour of data due to insufficient 

monitoring data, as defined in paragraph (f)(1)(iv) of this 

section.

(iv) Monitoring data are insufficient to constitute a valid 

hour of data, as used in paragraphs (f)(1)(ii) and (iii) of this 
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section, if measured values are unavailable due to monitoring 

system breakdowns, repairs, calibrated checks, or zero (lowlevel) and high level adjustments, for any of the 15-minute 

periods within the hour. For data compression systems approved 

under §63.1439(g)(3), monitoring data are insufficient to 

calculate a valid hour of data if there are less than four data 

measurements made during the hour.

(v) The periods listed in paragraphs (f)(1)(v)(A) through 

(D) of this section Periods of non-operation of the affected 

source (or portion thereof), resulting in cessation of the 

emissions to which the monitoring applies, are not considered to 

be part of the period of combustion, recovery, or recapture 

device operation, for the purposes of paragraphs (f)(1)(ii) and 

(iii) of this section.

(A) Start-ups;

(B) Shutdowns;

(C) Malfunctions; or

(D) Periods of non-operation of the affected source (or 

portion thereof), resulting in cessation of the emissions to 

which the monitoring applies.

(2) For storage vessels where the applicable monitoring 

plan does not specify continuous monitoring, an excursion is 

defined in paragraph (f)(2)(i) or (ii) of this section, as 

applicable.
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(i) If the monitoring plan specifies monitoring a parameter 

and recording its value at specific intervals (such as every 15 

minutes or every hour), either of the cases listed in paragraph 

(f)(2)(i)(A) or (B) of this section is considered a single 

excursion for the combustion device.

(A) When the average value of one or more parameters, 

averaged over the time during which the storage vessel is being 

filled (i.e., when the liquid level in the storage vessel is 

being raised), is above the maximum level or below the minimum 

level established for the given parameters.

(B) When monitoring data are insufficient. Monitoring data 

shall be considered insufficient when measured values are not 

available, due to monitoring system breakdowns, repairs, 

calibration checks, or zero (low-level) and high-level 

adjustments, for at least 75 percent of the specific intervals 

at which parameters are to be monitored and recorded, according 

to the storage vessel's monitoring plan, during which the 

storage vessel is being filled.

(ii) If the monitoring plan does not specify monitoring a 

parameter and recording its value at specific intervals (for 

example, if the relevant operating requirement is to exchange a 

disposable carbon canister before expiration of its rated 

service life), the monitoring plan shall define an excursion in 

terms of the relevant operating requirement.
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(3) With respect to process vents from batch unit 

operations, an excursion means one of the two cases listed in 

paragraphs (f)(3)(i) and (ii) of this section.

(i) When the daily average value of one or more monitored 

parameters is above the maximum or below the minimum established 

level for the given parameters.

(ii) When monitoring data are insufficient for an operating 

day. Monitoring data shall be considered insufficient when 

measured values are not available, due to monitoring system 

breakdowns, repairs, calibration checks, or zero (low-level) and 

high-level adjustments, for at least 75 percent of the 15-minute 

periods when batch emission episodes selected to be controlled 

are being vented to the control device during the operating day, 

using the procedures specified in paragraphs (f)(3)(ii)(A) 

through (D) of this section.

(A) Determine the total amount of time during the operating

day when batch emission episodes selected to be controlled are 

being vented to the control device.

(B) Subtract the time during the periods of non-operation 

of the affected source (or portion thereof), resulting in 

cessation of the emissions to which the monitoring applies, 

listed in paragraphs (f)(3)(ii)(B)(1) through (4) of this 

section from the total amount of time determined above in 
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paragraph (f)(3)(ii)(A) of this section, to obtain the operating 

time used to determine if monitoring data are insufficient.

(1) Start-ups;

(2) Shutdowns;

(3) Malfunctions; or

(4) Periods of non-operation of the affected source (or 

portion thereof), resulting in cessation of the emissions to 

which the monitoring applies.

(C) Determine the total number of 15-minute periods in the 

operating time used to determine if monitoring data are 

insufficient, as was determined in accordance with paragraph 

(f)(3)(ii)(B) of this section.

(D) If measured values are not available for at least 75 

percent of the total number of 15-minute periods determined in 

paragraph (f)(3)(ii)(C) of this section, the monitoring data are 

insufficient for the operating day.

(4) With respect to process vents using ECO to reduce 

epoxide emissions, an excursion means any of the situations 

described in §63.1427(i)(3)(i) through (v). For each excursion, 

the owner or operator shall be deemed out of compliance with the 

provisions of this subpart, in accordance with paragraph (e) of 

this section, except as provided in paragraph (g) of this 

section.
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(g) Excused excursions. A number of excused excursions 

shall be allowed for each combustion, recovery, or recapture 

device for each semiannual period. The number of excused 

excursions for each semiannual period is specified in paragraphs 

(g)(1) through (6) of this section. This paragraph applies to 

affected sources required to submit Periodic Reports 

semiannually or quarterly. The first semiannual period is the 6-

month period starting the date the Notification of Compliance 

Status is due.

(1) For the first semiannual period—six excused excursions.

(2) For the second semiannual period—five excused 

excursions.

(3) For the third semiannual period—four excused 

excursions.

(4) For the fourth semiannual period—three excused 

excursions.

(5) For the fifth semiannual period—two excused excursions.

(6) For the sixth and all subsequent semiannual periods—one 

excused excursion.

§63.1439 General recordkeeping and reporting provisions.

(a) Data retention. Unless otherwise specified in this 

subpart, the owner or operator of an affected source shall keep 

copies of all applicable records and reports required by this 

subpart for at least 5 years. All applicable records shall be 
Page 192 of 262

maintained in such a manner that they can be readily accessed. 

The most recent 6 months of records shall be retained on site or 

shall be accessible from a central location by computer or other 

means that provide access within 2 hours after a request. The 

remaining 4 and one-half years of records may be retained 

offsite. Records may be maintained in hard copy or computerreadable form including, but not limited to, on microfilm, 

computer, floppy disk, magnetic tape, or microfiche. If an owner 

or operator submits copies of reports to the applicable EPA 

Regional Office, the owner or operator is not required to

maintain copies of reports. If the EPA Regional Office has 

waived the requirement of §63.10(a)(4)(ii) for submittal of 

copies of reports, the owner or operator is not required to 

maintain copies of reports.

(b) Subpart A requirements. The owner or operator of an 

affected source shall comply with the applicable recordkeeping 

and reporting requirements in 40 CFR part 63, subpart A (the 

General Provisions) as specified in Table 1 of this subpart. 

These requirements include, but are not limited to, the 

requirements specified in paragraphs (b)(1) and (2) of this 

section.

(1) Start-up, shutdown, and mMalfunction recordkeeping and 

reporting plan. The owner or operator of an affected source 

shall develop a written startup, shutdown, and malfunction plan 
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as specified in §63.6(e)(3). This plan shall describe, in 

detail, procedures for operating and maintaining the affected 

source during periods of start-up, shutdown, and malfunction and 

a program for corrective action for malfunctioning process and 

air pollution control equipment used to comply with this 

subpart. A provision for ceasing to collect, during a start-up, 

shutdown, or malfunction, monitoring data that would otherwise 

be required by the provisions of this subpart may be included in 

the start-up, shutdown, and malfunction plan only if the owner 

or operator has demonstrated to the Administrator, through the 

Precompliance Report or a supplement to the Precompliance 

Report, that the monitoring system would be damaged or destroyed 

if it were not shut down during the start-up, shutdown, or 

malfunction. The owner or operator of the affected source shall 

keep the start-up, shutdown, and malfunction plan on site. In 

addition, if the start-up, shutdown, and malfunction plan is 

revised, the owner or operator shall keep previous (i.e., 

superseded) versions of the start-up, shutdown, and malfunction 

plan for a period of 5 years after each revision to the plan. If 

the new version of the start-up, shutdown, and malfunction plan 

includes a provision for ceasing to collect, during a start-up, 

shutdown, or malfunction, monitoring data that would otherwise 

be required, the owner or operator shall submit a supplement to 

the Precompliance Report to the Administrator for the 
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Administrator's approval, documenting that the monitoring system 

would be damaged or destroyed if it were not shut down during 

the start-up, shutdown, or malfunction. Records associated with 

the plan shall be kept as specified in paragraphs (b)(1)(i)(A) 

and (B) of this section. Reports related to the plan shall be 

submitted as specified in paragraph (b)(1)(ii) of this section.

(i) Records of malfunctions. The owner or operator shall 

keep the records specified in paragraphs (b)(1)(i)(A) and 

through (BC) of this section.

(A) In the event that an affected unit fails to meet an 

applicable standard, record the number of failures. For each 

failure record the date, time, and duration of each 

failure.Records of the occurrence and duration of each start-up, 

shutdown, and malfunction of operation of process equipment or 

combustion, recovery, or recapture devices or continuous 

monitoring systems used to comply with this subpart during which 

excess emissions (as defined in §63.1420(h)(4)) occur.

(B) For each failure to meet an applicable standard, record 

and retain a list of the affected sources or equipment, an 

estimate of the quantity of each regulated pollutant emitted 

over any emission limit, and a description of the method used to 

estimate the emissions.For each start-up, shutdown, or 

malfunction during which excess emissions (as defined in 

§63.1420(h)(4)) occur, records reflecting whether the procedures 
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specified in the affected source's start-up, shutdown, and 

malfunction plan were followed, and documentation of actions 

taken that are not consistent with the plan. For example, if a 

start-up, shutdown, and malfunction plan includes procedures for 

routing a combustion, recovery, or recapture device to a backup 

combustion, recovery, or recapture device, records shall be kept 

of whether the plan was followed. These records may take the 

form of a “checklist,” or other form of recordkeeping that 

confirms conformance with the start-up, shutdown, and 

malfunction plan for the event.

(C) Record actions taken to minimize emissions in 

accordance with §63.1420(h)(4), and any corrective actions taken 

to return the affected unit to its normal or usual manner of 

operation.

(ii) Reports of start-up, shutdown, and malfunctions. If a 

source fails to meet an applicable standard, report such events 

in the Periodic Report. Report the number of failures to meet an 

applicable standard. For each instance, report the date, time,

and duration of each failure. For each failure the report must 

include a list of the affected sources or equipment, an estimate 

of the quantity of each regulated pollutant emitted over any 

emission limit, and a description of the method used to estimate 

the emissions.For the purposes of this subpart, the semiannual 

start-up, shutdown, and malfunction reports shall be submitted 
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on the same schedule as the Periodic Reports required under 

paragraph (e)(6) of this section instead of according to the 

general provisions' Periodic Reporting schedule specified in 

§63.10(d)(5)(i). The reports shall include the information 

specified in §63.10(d)(5)(i).

(2) Application for approval of construction or 

reconstruction. For new affected sources, the owner or operator 

shall comply with the General Provisions' requirements for the 

application for approval of construction or reconstruction, as 

specified in §63.5, excluding the provisions specified in 

§63.5(d)(1)(ii)(H), (d)(1)(iii), (d)(2), and (d)(3)(ii).

(c) Subpart H requirements. The owner or operator of an 

affected source shall comply with the HON equipment leak 

reporting and recordkeeping requirements in 40 CFR part 63,

subpart H, except as specified in §63.1434(b) through (gh).

(d) Recordkeeping and documentation. The owner or operator 

required to keep continuous records shall keep records as 

specified in paragraphs (d)(1) through (710) of this section, 

unless an alternative recordkeeping system has been requested 

and approved as specified in paragraph (g) of this section, and 

except as provided in paragraph (h) of this section. If a 

monitoring plan for storage vessels pursuant to §63.1432(i) 

requires continuous records, the monitoring plan shall specify 

which provisions, if any, of paragraphs (d)(1) through (710) of 
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this section apply. As described in §63.1432(i), certain storage 

vessels are not required to keep continuous records as specified 

in this paragraph. The owner or operator of such storage vessels 

shall keep records as specified in the monitoring plan required 

by §63.1432(i).

(1) The monitoring system shall measure data values at 

least once during approximately equal 15-minute intervals.

(2) The owner or operator shall record either each measured 

data value or block average values for 1 hour or shorter periods 

calculated from all measured data values during each period. If 

values are measured more frequently than once per minute, a 

single value for each minute may be used to calculate the hourly 

(or shorter period) block average instead of all measured 

values. The owner or operator of process vents from batch unit 

operations shall record each measured data value.

(3) Daily average values of each continuously monitored 

parameter shall be calculated for each operating day as 

specified in paragraphs (d)(3)(i) through (ii) of this section, 

except as specified in paragraphs (d)(6) and (7) of this 

section.

(i) The daily average value shall be calculated as the 

average of all parameter values recorded during the operating 

day, except as specified in paragraph (d)(7) of this section. 

The calculated average shall cover a 24-hour period if operation 
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is continuous. If intermittent emissions episodes occur 

resulting in emissions being vented to a combustion, recapture, 

or recovery device for a period of less than 24 hours in the 

operating day, the daily average shall be calculated based only 

on the period when emissions are being vented to the combustion, 

recapture, or recovery device. For example, if a batch unit 

operation operates such that emissions are vented to a 

combustion device for 6 hours, then the daily average is the 

average of the temperature measurements taken during those 6 

hours.

(ii) The operating day shall be the 24-hour period that the 

owner or operator specifies in the operating permit or the 

Notification of Compliance Status, for purposes of determining 

daily average values.

(4)–(5) [Reserved]

(6) If all recorded values for a monitored parameter during 

an operating day are above the minimum level or below the 

maximum level established in the Notification of Compliance 

Status or operating permit, the owner or operator may record 

that all values were above the minimum level or below the 

maximum level rather than calculating and recording a daily 

average for that operating day.

(7) Monitoring data recorded during periods identified in 

paragraphs (d)(7)(i) through and (vii) of this section shall not 
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be included in any average computed under this subpart. Records 

shall be kept of the times and durations of all such periods and 

any other periods during process or combustion, recovery, or 

recapture device operation when monitors are not operating.

(i) Monitoring system breakdowns, repairs, calibration 

checks, and zero (low-level) and high-level adjustments; or

(ii) Start-ups;

(iii) Shutdowns;

(iv) Malfunctions; or

(v) Periods of non-operation of the affected source (or 

portion thereof), resulting in cessation of the emissions to 

which the monitoring applies.

(8) For continuous monitoring systems used to comply with 

this subpart, records documenting the completion of calibration 

checks, and records documenting the maintenance of continuous 

monitoring systems that are specified in the manufacturer's 

instructions or that are specified in other written procedures 

that provide adequate assurance that the equipment would 

reasonably be expected to monitor accurately.

(9) The owner or operator of an affected source granted a 

waiver of recordkeeping or reporting requirements under the 

General Provisions' recordkeeping and reporting requirements in 

§63.10(f) shall maintain the information, if any, specified by 
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the Administrator as a condition of the waiver of recordkeeping 

or reporting requirements.

(10) For pressure relief devices in organic HAP service, 

keep records of the information specified in paragraphs 

(d)(10)(i) through (v) of this section, as applicable.

(i) A list of identification numbers for pressure relief 

devices that the owner or operator elects to equip with a 

closed-vent system and control device, subject to the provisions 

in §63.1434(c)(4).

(ii) A list of identification numbers for pressure relief 

devices subject to the provisions in §63.1434(c)(1).

(iii) A list of identification numbers for pressure relief 

devices equipped with rupture disks, subject to the provisions 

in §63.1434(c)(2)(ii).

(iv) The dates and results of the Method 21 of 40 CFR part 

60, appendix A, monitoring following a pressure release for each 

pressure relief device subject to the provisions in

§63.1434(c)(1) and (2). The results shall include:

(A) The background level measured during each compliance 

test.

(B) The maximum instrument reading measured at each piece 

of equipment during each compliance test.
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(v) For pressure relief devices in organic HAP service 

subject to §63.1434(c)(3), keep records of each pressure release 

to the atmosphere, including the following information:

(A) The source, nature, and cause of the pressure release.

(B) The date, time, and duration of the pressure release.

(C) The quantity of total HAP emitted during the pressure 

release and the calculations used for determining this quantity.

(D) The actions taken to prevent this pressure release.

(E) The measures adopted to prevent future such pressure 

releases.

(e) Reporting and notification. In addition to the reports 

and notifications required by 40 CFR part 63, subpart A, as 

specified in this subpart, the owner or operator of an affected 

source shall prepare and submit the reports listed in paragraphs 

(e)(3) through (89) of this section, as applicable. All reports 

required by this subpart, and the schedule for their submittal, 

are listed in Table 8 of this subpart.

(1) Violation of reporting requirements. Owners and 

operators shall not be in violation of the reporting 

requirements of this paragraph (e) for failing to submit 

information required to be included in a specified report if the 

owner or operator meets the requirements in paragraphs (e)(1)(i) 

through (iii) of this section. Examples of circumstances where 

this paragraph may apply include information related to newly-
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added equipment or emission points, changes in the process, 

changes in equipment required or utilized for compliance with 

the requirements of this subpart, or changes in methods or 

equipment for monitoring, recordkeeping, or reporting.

(i) The information was not known in time for inclusion in 

the report specified by this subpart.

(ii) The owner or operator has been diligent in obtaining 

the information.

(iii) The owner or operator submits a report according to 

the provisions of paragraphs (e)(1)(iii)(A) through (C) of this 

section.

(A) If this subpart expressly provides for supplements to 

the report in which the information is required, the owner or 

operator shall submit the information as a supplement to that 

report. The information shall be submitted no later than 60 days 

after it is obtained, unless otherwise specified in this 

subpart.

(B) If this subpart does not expressly provide for 

supplements, but the owner or operator must submit a request for 

revision of an operating permit pursuant to the State operating 

permit programs in part 70 or the Federal operating permit 

programs in part 71, due to circumstances to which the 

information pertains, the owner or operator shall submit the 
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information with the request for revision to the operating 

permit.

(C) In any case not addressed by paragraph (e)(1)(iii)(A) 

or (B) of this section, the owner or operator shall submit the 

information with the first Periodic Report, as required by this 

subpart, which has a submission deadline at least 60 days after 

the information is obtained.

(2) Submittal of reports. All reports required under this 

subpart shall be sent to the Administrator at the applicable 

address listed in the General Provisions' list of addresses of 

State air pollution control agencies and EPA Regional Offices, 

in §63.13. If acceptable to both the Administrator and the owner 

or operator of a source, reports may be submitted on electronic 

media.

(3) Initial Notification. The owner or operator of a new 

affected source shall submit a written Initial Notification to 

the Administrator containing the information described in 

paragraph (e)(3)(i) of this section according to the schedule in 

paragraph (e)(3)(ii) of this section. The General Provisions' 

Initial Notification requirements in §63.9(b)(2), ) and (3), and 

(6) shall not apply for the purposes of this subpart.

(i) The Initial Notification shall include the following 

information:

(A) The name and address of the owner or operator;
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(B) The address (physical location) of the affected source;

(C) An identification of the kinds of emission points 

within the affected source;

(D) An identification of the relevant standard, or other 

requirement, that is the basis of the notification and the 

source's compliance date; and

(E) A statement of whether or not the affected source is a 

major source.

(ii) The Initial Notification shall be submitted according 

to the schedule in paragraph (e)(3)(ii)(A), (B), or (C) of this 

section, as applicable.

(A) [Reserved]

(B) For a new source that has an initial start-up on or 

after August 30, 1999, the application for approval of 

construction or reconstruction required by the General 

Provisions in §63.5(d) shall be submitted in lieu of the Initial 

Notification. The application shall be submitted as soon as 

practical before construction or reconstruction is planned to 

commence (but it need not be sooner than August 30, 1999).

(C) For a new source that has an initial start-up prior to 

August 30, 1999, the Initial Notification shall be submitted no 

later than August 30, 1999. The application for approval of 

construction or reconstruction described in the General 
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Provisions' requirements in §63.5(d) is not required for these 

sources.

(4) Precompliance Report. The owner or operator of an 

affected source requesting an extension for compliance; 

requesting approval to use alternative monitoring parameters, 

alternative continuous monitoring and recordkeeping, or 

alternative controls; requesting approval to incorporate a 

provision for ceasing to collect monitoring data, during a 

start-up, shutdown, or malfunction, into the start-up, shutdown, 

and malfunction plan, when that monitoring equipment would be 

damaged if it did not cease to collect monitoring data, as 

permitted under §63.1420(h)(3); or requesting approval to 

establish parameter monitoring levels according to the 

procedures contained in §63.1438(c) or (d) shall submit a 

Precompliance Report according to the schedule described in 

paragraph (e)(4)(i) of this section. The Precompliance Report

shall contain the information specified in paragraphs (e)(4)(ii) 

through (viii) of this section, as appropriate.

(i) The Precompliance Report shall be submitted to the 

Administrator no later than 12 months prior to the compliance 

date. Unless the Administrator objects to a request submitted in 

the Precompliance Report within 45 days after its receipt, the 

request shall be deemed approved. For new affected sources, the 

Precompliance Report shall be submitted to the Administrator 
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with the application for approval of construction or 

reconstruction required in paragraph (b)(2) of this section. 

Supplements to the Precompliance Report may be submitted as 

specified in paragraph (e)(4)(vii) of this section. To submit a 

Precompliance Report for the first time after the compliance 

date to request an extension for compliance; request approval to 

use alternative monitoring parameters, alternative continuous 

monitoring and recordkeeping, or alternative controls; or 

request approval to establish parameter monitoring levels 

according to the procedures contained in §63.1438(c) or (d), the 

owner or operator shall notify the Administrator at least 90 

days before the planned change is to be implemented; the change 

shall be considered approved if the Administrator either 

approves the change in writing, or fails to disapprove the 

change in writing within 45 days of receipt.

(ii) A request for an extension for compliance, as 

specified in §63.1422(e), may be submitted in the Precompliance 

Report. The request for a compliance extension shall include the 

data outlined in the General Provisions' compliance requirements 

in §63.6(i)(6)(i)(A), and (B), and (D), as required in 

§63.1422(e)(1).

(iii) The alternative monitoring parameter information 

required in paragraph (f) of this section shall be submitted in 

the Precompliance Report if, for any emission point, the owner 
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or operator of an affected source seeks to comply through the 

use of a control technique other than those for which monitoring 

parameters are specified in this subpart or in 40 CFR part 63, 

subpart G, or seeks to comply by monitoring a different 

parameter than those specified in this subpart or in 40 CFR part 

63, subpart G.

(iv) If the affected source seeks to comply using 

alternative continuous monitoring and recordkeeping as specified 

in paragraph (g) of this section, the owner or operator shall 

submit a request for approval in the Precompliance Report.

(v) The owner or operator shall report the intent to use an 

alternative controls emission standard to comply with the 

provisions of this subpart in the Precompliance Report. The 

Administrator may deem an alternative controls emission standard 

to be equivalent to the controls standard required by the 

standardsubpart, under the procedures outlined in the General 

Provisions' requirements for use of an alternative nonopacity 

emission standard, in §63.6(g).

(vi) If the owner or operator is requesting approval to 

incorporate a provision for ceasing to collect monitoring data, 

during a start-up, shutdown, or malfunction, into the start-up, 

shutdown, and malfunction plan, when that monitoring equipment 

would be damaged if it did not cease to collect monitoring data, 

the information specified in paragraphs (e)(4)(vi)(A) and (B) of 
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this section shall be supplied in the Precompliance Report or in 

a supplement to the Precompliance Report. The Administrator 

shall evaluate the supporting documentation and shall approve 

the request only if, in the Administrator's judgment, the 

specific monitoring equipment would be damaged by the 

contemporaneous start-up, shutdown, or malfunction.

(A) Documentation supporting a claim that the monitoring 

equipment would be damaged by the contemporaneous start-up, 

shutdown, or malfunction; and

(B) A request to incorporate such a provision for ceasing 

to collect monitoring data during a start-up, shutdown, or 

malfunction, into the start-up, shutdown, and malfunction 

plan.[Reserved]

(vii) Supplements to the Precompliance Report may be 

submitted as specified in paragraph (e)(4)(vii)(A) of this 

section, or as specified in paragraph (e)(4)(vii)(B) of this 

section. Unless the Administrator objects to a request submitted 

in a supplement to the Precompliance Report within 45 days after 

its receipt, the request shall be deemed approved.

(A) Supplements to the Precompliance Report may be 

submitted to clarify or modify information previously submitted.

(B) Supplements to the Precompliance Report may be 

submitted to request approval to use alternative monitoring 

parameters, as specified in paragraph (e)(4)(iii) of this 
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section; to use alternative continuous monitoring and 

recordkeeping, as specified in paragraph (e)(4)(iv) of this 

section; or to use alternative controls, as specified in 

paragraph (e)(4)(v) of this section; or to include a provision 

for ceasing to collect monitoring data during a start-up, 

shutdown, or malfunction, in the start-up, shutdown, and 

malfunction plan, when that monitoring equipment would be 

damaged if it did not cease to collect monitoring data, as 

specified in paragraph (e)(4)(vi) of this section.

(viii) If an owner or operator establishes parameter 

monitoring levels according to the procedures contained in the 

parameter monitoring provisions in §63.1438(c) or (d), the 

following information shall be submitted in the Precompliance

Report:

(A) Identification of which procedures (i.e., §63.1438(c) 

or (d)) are to be used; and

(B) A description of how the parameter monitoring level is 

to be established. If the procedures in §63.1438(c) are to be 

used, a description of how performance test data will be used 

shall be included.

(5) Notification of Compliance Status. For existing and new 

affected sources, a Notification of Compliance Status shall be 

submitted within 150 days after the compliance dates specified 

in §63.1422. For equipment leaks subject to §63.1434, the owner 
Page 210 of 262

or operator shall submit the information specified in the HON 

equipment leak Notification of Compliance Status requirements in 

§63.182(c), in the Notification of Compliance Status required by 

this paragraph. For all other emission points, including heat 

exchange systems, the Notification of Compliance Status shall 

contain the information listed in paragraphs (e)(5)(i) through 

(vii) of this section. For pressure relief devices subject to 

the requirements of §63.1434(c)(3), the owner or operator shall 

submit the information listed in paragraph (e)(5)(viii) of this 

section in the Notification of Compliance Status within 150 days 

after the first applicable compliance date for pressure relief 

device monitoring.

(i) The results of any emission point group determinations, 

process section applicability determinations, performance tests, 

inspections, continuous monitoring system performance 

evaluations, any other information required by the test method 

to be in the test report used to demonstrate compliance, values 

of monitored parameters established during performance tests, 

and any other information required to be included in a 

Notification of Compliance Status under the requirements for 

overlapping regulations in §63.1422(j), the HON storage vessel 

reporting provisions in §63.122 and the storage vessel 

provisions in §63.1432, and the HON process wastewater reporting 
Page 211 of 262

provisions in §63.146. In addition, the owner or operator shall 

comply with paragraphs (e)(5)(i)(A) and (B) of this section.

(A) For performance tests, group determinations, or 

determination that controls are needed, the Notification of 

Compliance Status shall include one complete test report, as 

described in paragraph (e)(5)(i)(B) of this section, for each 

test method used for a particular kind of emission point. For 

additional tests performed for the same kind of emission point 

using the same method, the results and any other information 

required by the test method to be in the test report shall be 

submitted, but a complete test report is not required.

(B) A complete test report shall include a brief process 

description, sampling site description, description of sampling 

and analysis procedures and any modifications to standard 

procedures, quality assurance procedures, record of operating 

conditions during the test, record of preparation of standards 

(if the owner or operator prepares the standards), record of 

calibrations, raw data sheets for field sampling, raw data 

sheets for field and laboratory analyses, documentation of 

calculations, and any other information required by the test 

method to be in the test report.

(ii) For each monitored parameter for which a maximum or 

minimum level is required to be established under the HON 

process vent monitoring requirements in §63.114(e) and the 
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process vent monitoring requirements in §63.1429(d), the HON 

process wastewater parameter monitoring requirements in 

§63.143(f), paragraph (e)(8) of this section, or paragraph (f) 

of this section, the information specified in paragraphs 

(e)(5)(ii)(A) through (C) of this section shall be submitted. 

Further, as described in the storage vessel provisions in 

§63.1432(k), for those storage vessels for which the parameter 

monitoring plan (required to be submitted under the HON 

Notification of Compliance Status requirements for storage 

vessels in §63.120(d)(3)) specifies compliance with the 

parameter monitoring provisions of §63.1438, the owner or 

operator shall provide the information specified in paragraphs 

(e)(5)(ii)(A) through (C) of this section for each monitoring 

parameter. For those storage vessels for which the parameter 

monitoring plan required to be submitted under the HON 

Notification of Compliance Status requirements for storage 

vessels in §63.120(d)(2) does not require compliance with the 

provisions of §63.1438, the owner or operator shall provide the 

information specified in §63.120(d)(3) as part of the 

Notification of Compliance Status.

(A) The required information shall include the specific 

maximum or minimum level of the monitored parameter(s) for each 

emission point.
Page 213 of 262

(B) The required information shall include the rationale 

for the specific maximum or minimum level for each parameter for 

each emission point, including any data and calculations used to 

develop the level and a description of why the level indicates 

that the combustion, recovery, or recapture device is operated 

in a manner to ensure compliance with the provisions of this 

subpart.

(C) The required information shall include a definition of 

the affected source's operating day, as specified in paragraph 

(d)(3)(ii) of this section, for purposes of determining daily 

average values of monitored parameters.

(iii) The determination of applicability for flexible 

operation units as specified in §63.1420(e)(1)(iii).

(iv) The parameter monitoring levels for flexible operation 

units, and the basis on which these levels were selected, or a 

demonstration that these levels are appropriate at all times, as 

specified in §63.1420(e)(5)(ii)(A).

(v) The results for each predominant use determination made 

under §63.1420(f)(1) through (7), for storage vessels assigned 

to an affected source subject to this subpart.

(vi) If any emission point is subject to this subpart and 

to other standards as specified in §63.1422(j), and if the 

provisions of §63.1422(j) allow the owner or operator to choose 

which testing, monitoring, reporting, and recordkeeping 
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provisions will be followed, then the Notification of Compliance 

Status shall indicate which rule's requirements will be followed 

for testing, monitoring, reporting, and recordkeeping.

(vii) An owner or operator who transfers a Group 1 

wastewater stream or residual removed from a Group 1 wastewater 

stream for treatment pursuant to §63.132(g) shall include in the 

Notification of Compliance Status the name and location of the 

transferee and a description of the Group 1 wastewater stream or 

residual sent to the treatment facility. An owner or operator 

who transfers a Group 1 process vent for disposal pursuant to 

§63.113(i) shall include in the Notification of Compliance 

Status the name and location of the transferee and the 

identification of the Group 1 process vent.

(viii) For pressure relief devices in organic HAP service, 

a description of the device or monitoring system to be 

implemented, including the pressure relief devices and process 

parameters to be monitored (if applicable), a description of the 

alarms or other methods by which operators will be notified of a 

pressure release, and a description of how the owner or operator 

will determine the information to be recorded under paragraph 

(d)(10)(v)(B)-(C) of this section (i.e., the duration of the 

pressure release and the methodology and calculations for 

determining of the quantity of total HAP emitted during the 

pressure release).
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(6) Periodic Reports. For existing and new affected 

sources, the owner or operator shall submit Periodic Reports as 

specified in paragraphs (e)(6)(i) through (viiix) of this 

section. In addition, for equipment leaks subject to §63.1434, 

the owner or operator shall submit the information specified in 

the HON periodic reporting requirements in §63.182(d), and for 

heat exchange systems subject to §63.1434, the owner or operator 

shall submit the information specified in the HON heat exchange 

system reporting requirements in §63.104(f)(2), as part of the 

Periodic Report required by this paragraph (e)(6).

(i) Except as specified in paragraphs (e)(6)(viii) of this 

section, a report containing the information in paragraph 

(e)(6)(ii) of this section or paragraphs (e)(6)(iii) through 

(vii) of this section, as appropriate, shall be submitted 

semiannually no later than 60 days after the end of each 180-day 

period. The first report shall be submitted no later than 240 

days after the date the Notification of Compliance Status is due 

and shall cover the 6-month period beginning on the date the 

Notification of Compliance Status is due. Subsequent reports 

shall cover each preceding 6-month period.

(ii) If none of the compliance exceptions in paragraphs 

(e)(6)(iii) through (vii) of this section occurred during the 6-

month period, the Periodic Report required by paragraph 

(e)(6)(i) of this section shall be a statement that there were 
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no compliance exceptions, as described in this paragraph, for 

the 6-month period covered by that report and that none of the 

activities specified in paragraphs (e)(6)(iii) through (vii) of 

this section occurred during the period covered by that report.

(iii) For an owner or operator of an affected source 

complying with the provisions of §§63.1432 through 63.1433 for 

any emission point, Periodic Reports shall include:

(A) All information specified in the HON periodic reporting 

requirements in §63.122(a)(4) for storage vessels and in 

§63.146(c) through §63.146(f) for process wastewater.

(B) The daily average values of monitored parameters for 

all excursions, as defined in §63.1438(f).

(C) The periods when monitoring data were not collected 

shall be specified; and

(D) The information in paragraphs (e)(6)(iii)(D)(1) through 

(3) of this section, as applicable:

(1) Notification if a process change is made such that the 

group status of any emission point changes from Group 2 to Group 

1. The owner or operator is not required to submit a 

notification of a process change if that process change caused 

the group status of an emission point to change from Group 1 to 

Group 2. However, until the owner or operator notifies the 

Administrator that the group status of an emission point has 

changed from Group 1 to Group 2, the owner or operator is 
Page 217 of 262

required to continue to comply with the Group 1 requirements for 

that emission point. This notification may be submitted at any 

time.

(2) Notification if one or more emission points (other than 

equipment leak components subject to §63.1434), or one or more 

PMPU is added to an affected source. The owner or operator shall 

submit the information contained in paragraphs 

(e)(6)(iii)(D)(2)(i) and (ii) of this section.

(i) A description of the addition to the affected source.

(ii) Notification of the group status or control 

requirement for the additional emission point or all emission 

points in the PMPU.

(3) For gas streams sent for disposal pursuant to 

§63.113(i) or for process wastewater streams sent for treatment 

pursuant to §63.132(g), reports of changes in the identity of 

the treatment facility or transferee.

(E) The information in paragraph (b)(1)(ii) of this section 

for reports of start-up, shutdown, and malfunctions.

(iv) If any performance tests are reported in a Periodic 

Report, the following information shall be included:

(A) One complete test report shall be submitted for each 

test method used for a particular kind of emission point tested. 

A complete test report shall contain the information specified 

in paragraph (e)(5)(i)(B) of this section.
Page 218 of 262

(B) For additional tests performed for the same kind of 

emission point using the same method, results and any other 

information required by the test method to be in the test report 

shall be submitted, but a complete test report is not required.

(v) The results for each change made to a primary product 

determination for a PMPU made under §63.1420(e)(3) or (10).

(vi) The results for each reevaluation of the applicability 

of this subpart to a storage vessel that begins receiving 

material from (or sending material to) a process unit that was 

not included in the initial determination, or a storage vessel 

that ceases to receive material from (or send material to) a 

process unit that was included in the initial determination, in 

accordance with §63.1420(f)(8).

(vii) The Periodic Report required by the equipment leak

provisions in §63.1434(f) shall be submitted as part of the 

Periodic Report required by paragraph (e)(6) of this section.

(viii) The owner or operator of an affected source shall 

submit quarterly reports for particular emission points and 

process sections as specified in paragraphs (e)(6)(viii)(A) 

through (D) of this section.

(A) The owner or operator of an affected source shall 

submit quarterly reports for a period of 1 year for an emission 

point or process section if the emission point or process 
Page 219 of 262

section meets the conditions in paragraph (e)(6)(viii)(A)(1) or 

(2) of this section.

(1) A combustion, recovery, or recapture device for a 

particular emission point or process section has one or more 

excursions, as defined in §63.1438(f), than the number of 

excused excursions allowed under §63.1438(g) for a in two 

consecutive semiannual reporting periods; or

(2) The Administrator requests the owner or operator to 

submit quarterly reports for that emission point or process 

section.

(B) The quarterly reports shall include all information 

specified in paragraphs (e)(6)(iii) through (vii) of this 

section, as applicable to the emission point or process section 

for which quarterly reporting is required under paragraph 

(e)(6)(viii)(A) of this section. Information applicable to other 

emission points within the affected source shall be submitted in 

the semiannual reports required under paragraph (e)(6)(i) of 

this section.

(C) Quarterly reports shall be submitted no later than 60 

days after the end of each quarter.

(D) After quarterly reports have been submitted for an 

emission point for 1 year without one or more excursions 

occurring (during that year) than the number of excused 

excursions allowed under §63.1438(g), the owner or operator may 
Page 220 of 262

return to semiannual reporting for the emission point or process 

section.

(ix) For pressure relief devices in organic HAP service, 

Periodic Reports must include the information specified in 

paragraphs (e)(6)(ix)(A) through (C) of this section.

(A) For pressure relief devices in organic HAP service 

subject to §63.1434(c), report confirmation that all monitoring 

to show compliance was conducted within the reporting period.

(B) For pressure relief devices in organic HAP gas or vapor 

service subject to §63.1434(c)(2), report any instrument reading 

of 500 ppm above background or greater, more than 5 calendar 

days after the pressure release.

(C) For pressure relief devices in organic HAP service 

subject to §63.1434(c)(3), report each pressure release to the 

atmosphere, including the following information:

(1) The source, nature, and cause of the pressure release.

(2) The date, time, and duration of the pressure release.

(3) The quantity of total HAP emitted during the pressure 

release and the method used for determining this quantity.

(4) The actions taken to prevent this pressure release.

(5) The measures adopted to prevent future such pressure 

releases.

(7) Other reports. Other reports shall be submitted as 

specified in paragraphs (e)(7)(i) through (iii) of this section.
Page 221 of 262

(i) For storage vessels, the notifications of inspections 

required by §63.1432 shall be submitted, as specified in the HON 

storage vessel provisions in §63.122(h)(1) and (2).

(ii) When the conditions at §63.1420(e)(3)(iii), (e)(9), or 

(e)(10) are met, reports of changes to the primary product for a 

PMPU or process unit, as required by §63.1420(e)(3)(iii), 

(e)(9), or (e)(10)(iii), respectively, shall be submitted.

(iii) Owners or operators of PMPU or emission points (other 

than equipment leak components subject to §63.1434) that are 

subject to provisions for changes or additions to plant sites in 

§63.1420(g)(1) or (2) shall submit a report as specified in 

paragraphs (e)(7)(iii)(A) and (B) of this section.

(A) Reports shall include:

(1) A description of the process change or addition, as 

appropriate;

(2) The planned start-up date and the appropriate 

compliance date, according to §63.1420(g)(1) or (2); and

(3) Identification of the group status of emission points 

(except equipment leak components subject to the requirements in 

§63.1434) specified in paragraphs (e)(7)(iii)(A)(3)(i) through 

(iii) of this section, as applicable.

(i) All the emission points in the added PMPU, as described 

in §63.1420(g)(1).
Page 222 of 262

(ii) All the emission points in an affected source 

designated as a new affected source under §63.1420(g)(2)(i).

(iii) All the added or created emission points as described 

in §63.1420(g)(2)(ii) or (iii).

(4) If the owner or operator wishes to request approval to 

use alternative monitoring parameters, alternative continuous 

monitoring or recordkeeping, alternative controls, or wishes to 

establish parameter monitoring levels according to the 

procedures contained in §63.1438(c) or (d), a Precompliance 

Report shall be submitted in accordance with paragraph 

(e)(7)(iii)(B) of this section.

(B) Reports shall be submitted as specified in paragraphs 

(e)(7)(iii)(B)(1) through (3) of this section, as appropriate.

(1) Owners or operators of an added PMPU subject to 

§63.1420(g)(1) shall submit a report no later than 180 days 

prior to the compliance date for the PMPU.

(2) Owners or operators of an affected source designated as 

a new affected source under §63.1420(g)(2)(i) shall submit a 

report no later than 180 days prior to the compliance date for 

the affected source.

(3) Owners and operators of any emission point (other than 

equipment leak components subject to §63.1434) subject to 

§63.1420(g)(2)(ii) or (iii) shall submit a report no later than 

180 days prior to the compliance date for those emission points.
Page 223 of 262

(8) Operating permit application. An owner or operator who 

submits an operating permit application instead of a 

Precompliance Report shall submit the information specified in 

paragraph (e)(4) of this section, as applicable, with the 

operating permit application.

(9) Electronic reporting. Within 60 days after the date of 

completing each performance test (as defined in §63.2), the 

owner or operator must submit the results of the performance 

tests, including any associated fuel analyses, required by this 

subpart according to the methods specified in paragraph 

(e)(9)(i) or (ii) of this section.

(i) For data collected using test methods supported by the 

EPA-provided software, the owner or operator shall submit the 

results of the performance test to the EPA by direct computerto-computer electronic transfer via EPA-provided software, 

unless otherwise approved by the Administrator. Owners or 

operators, who claim that some of the information being 

submitted for performance tests is confidential business 

information (CBI), must submit a complete file using EPAprovided software that includes information claimed to be CBI on 

a compact disk, flash drive, or other commonly used electronic 

storage media to the EPA. The electronic media must be clearly 

marked as CBI and mailed to U.S. EPA/OAPQS/CORE CBI Office, 

Attention: WebFIRE Administrator, MD C404-02, 4930 Old Page Rd., 
Page 224 of 262

Durham, NC 27703. The same file with the CBI omitted must be 

submitted to the EPA by direct computer-to-computer electronic 

transfer via EPA-provided software.

(ii) For any performance test conducted using test methods 

that are not compatible with the EPA-provided software, the 

owner or operator shall submit the results of the performance 

test to the Administrator at the appropriate address listed in 

§60.4.

(f) Alternative monitoring parameters. The owner or 

operator who has been directed by any section of this subpart, 

or any section of another subpart referenced by this subpart, 

that specifically references this paragraph to set unique 

monitoring parameters, or who requests approval to monitor a 

different parameter than those listed in §63.1432 for storage 

vessels, §63.1427 for ECO, §63.1429 for process vents, or 

§63.143 for process wastewater shall submit the information 

specified in paragraphs (f)(1) through (3) of this section in 

the Precompliance Report, as required by paragraph (e)(4) of 

this section. The owner or operator shall retain for a period of 

5 years each record required by paragraphs (f)(1) through (3) of 

this section.

(1) The required information shall include a description of 

the parameter(s) to be monitored to ensure the combustion, 

recovery, or recapture device; control technique; or pollution 
Page 225 of 262

prevention measure is operated in conformance with its design 

and achieves the specified emission limit, percent reduction, or 

nominal efficiency, and an explanation of the criteria used to 

select the parameter(s).

(2) The required information shall include a description of 

the methods and procedures that will be used to demonstrate that 

the parameter indicates proper operation, the schedule for this 

demonstration, and a statement that the owner or operator will 

establish a level for the monitored parameter as part of the 

Notification of Compliance Status report required in paragraph 

(e)(5) of this section, unless this information has already been 

included in the operating permit application.

(3) The required information shall include a description of 

the proposed monitoring, recordkeeping, and reporting system, to 

include the frequency and content of monitoring, recordkeeping, 

and reporting. Further, the rationale for the proposed 

monitoring, recordkeeping, and reporting system shall be 

included if either condition in paragraph (f)(3)(i) or (ii) of 

this section is met:

(i) If monitoring and recordkeeping is not continuous; or

(ii) If reports of daily average values will not be 

included in Periodic Reports when the monitored parameter value 

is above the maximum level or below the minimum level as 
Page 226 of 262

established in the operating permit or the Notification of 

Compliance Status.

(g) Alternative continuous monitoring and recordkeeping. An 

owner or operator choosing not to implement the continuous 

parameter operating and recordkeeping provisions listed in 

§63.1429 for process vents, and §63.1433 for wastewater, may 

instead request approval to use alternative continuous 

monitoring and recordkeeping provisions according to the 

procedures specified in paragraphs (g)(1) through (4) of this 

section. Requests shall be submitted in the Precompliance Report 

as specified in paragraph (e)(4)(iv) of this section, and shall 

contain the information specified in paragraphs (g)(2)(ii) and 

(g)(3)(ii) of this section, as applicable.

(1) The provisions in the General Provisions requirements 

for the use of an alternative monitoring method in 

§63.8(f)(5)(i) shall govern the review and approval of requests.

(2) An owner or operator of an affected source that does 

not have an automated monitoring and recording system capable of 

measuring parameter values at least once during approximately 

equal 15-minute intervals and that does not generate continuous 

records may request approval to use a nonautomated system with 

less frequent monitoring, in accordance with paragraphs 

(g)(2)(i) and (ii) of this section.
Page 227 of 262

(i) The requested system shall include visual reading and 

recording of the value of the relevant operating parameter no 

less frequently than once per hour. Daily averages shall be 

calculated from these hourly values and recorded.

(ii) The request shall contain:

(A) A description of the planned monitoring and 

recordkeeping system;

(B) Documentation that the affected source does not have an 

automated monitoring and recording system;

(C) Justification for requesting an alternative monitoring 

and recordkeeping system; and

(D) Demonstration that the proposed monitoring frequency is 

sufficient to represent combustion, recovery, or recapture 

device operating conditions, considering typical variability of 

the specific process and combustion, recovery, or recapture 

device operating parameter being monitored.

(3) An owner or operator may request approval to use an 

automated data compression recording system that does not record 

monitored operating parameter values at a set frequency (for 

example, once at approximately equal intervals of about 15 

minutes), but that records all values that meet set criteria for 

variation from previously recorded values, in accordance with 

paragraphs (g)(3)(i) and (ii) of this section.

(i) The requested system shall be designed to:
Page 228 of 262

(A) Measure the operating parameter value at least once

during approximately equal 15-minute intervals;

(B) Record at least four values each hour during periods of 

operation;

(C) Record the date and time when monitors are turned off 

or on;

(D) Recognize unchanging data that may indicate the monitor 

is not functioning properly, alert the operator, and record the 

incident;

(E) Calculate daily average values of the monitored 

operating parameter based on all measured data; and

(F) If the daily average is not an excursion, as defined in 

§63.1438(f), the data for that operating day may be converted to 

hourly average values and the four or more individual records 

for each hour in the operating day may be discarded.

(ii) The request shall contain:

(A) A description of the monitoring system and data 

compression recording system, including the criteria used to 

determine which monitored values are recorded and retained;

(B) The method for calculating daily averages; and

(C) A demonstration that the system meets all criteria in 

paragraph (g)(3)(i) of this section.

(4) An owner or operator may request approval to use other 

alternative monitoring systems according to the procedures 
Page 229 of 262

specified in the General Provisions' requirements for using an 

alternative monitoring method in §63.8(f)(4).

(h) Reduced recordkeeping program. For any parameter with 

respect to any item of equipment, the owner or operator may 

implement the recordkeeping requirements in paragraph (h)(1) or 

(2) of this section as alternatives to the continuous operating 

parameter monitoring and recordkeeping provisions that would 

otherwise apply under this subpart. The owner or operator shall 

retain for a period of 5 years each record required by paragraph 

(h)(1) or (2) of this section.

(1) The owner or operator may retain only the daily average 

value, and is not required to retain more frequent monitored 

operating parameter values, for a monitored parameter with 

respect to an item of equipment, if the requirements of 

paragraphs (h)(1)(i) through (iv) of this section are met. An 

owner or operator electing to comply with the requirements of 

paragraph (h)(1) of this section shall notify the Administrator 

in the Notification of Compliance Status or, if the Notification 

of Compliance Status has already been submitted, in the Periodic 

Report immediately preceding implementation of the requirements 

of paragraph (h)(1) of this section.

(i) The monitoring system is capable of detecting 

unrealistic or impossible data during periods of operation other 

than start-ups, shutdowns or malfunctions (e.g., a temperature 
Page 230 of 262

reading of −200 °C on a boiler), and will alert the operator by 

alarm or other means. The owner or operator shall record the 

occurrence. All instances of the alarm or other alert in an 

operating day constitute a single occurrence.

(ii) The monitoring system generates, updated at least 

hourly throughout each operating day, a running average of the 

monitoring values that have been obtained during that operating 

day, and the capability to observe this running average is 

readily available to the Administrator on-site during the 

operating day. The owner or operator shall record the occurrence 

of any period meeting the criteria in paragraphs (h)(1)(ii)(A) 

through and (CB) of this section. All instances in an operating 

day constitute a single occurrence.

(A) The running average is above the maximum or below the 

minimum established limits; and

(B) The running average is based on at least six 1-hour 

average values.; and

(C) The running average reflects a period of operation 

other than a start-up, shutdown, or malfunction.

(iii) The monitoring system is capable of detecting 

unchanging data during periods of operation other than startups, shutdowns or malfunctions, except in circumstances where 

the presence of unchanging data are the expected operating 

condition based on past experience (e.g., pH in some scrubbers), 
Page 231 of 262

and will alert the operator by alarm or other means. The owner 

or operator shall record the occurrence. All instances of the 

alarm or other alert in an operating day constitute a single 

occurrence.

(iv) The monitoring system will alert the owner or operator 

by an alarm or other means, if the running average parameter 

value calculated under paragraph (h)(1)(ii) of this section 

reaches a set point that is appropriately related to the 

established limit for the parameter that is being monitored.

(v) The owner or operator shall verify the proper 

functioning of the monitoring system, including its ability to 

comply with the requirements of paragraph (h)(1) of this 

section, at the times specified in paragraphs (h)(1)(v)(A) 

through (C) of this section. The owner or operator shall 

document that the required verifications occurred.

(A) Upon initial installation.

(B) Annually after initial installation.

(C) After any change to the programming or equipment 

constituting the monitoring system, which might reasonably be 

expected to alter the monitoring system's ability to comply with 

the requirements of this section.

(vi) The owner or operator shall retain the records 

identified in paragraphs (h)(1)(vi)(A) through (D) of this 

section.
Page 232 of 262

(A) Identification of each parameter, for each item of 

equipment, for which the owner or operator has elected to comply 

with the requirements of paragraph (h) of this section.

(B) A description of the applicable monitoring system(s), 

and how compliance will be achieved with each requirement of 

paragraphs (h)(1)(i) through (v) of this section. The 

description shall identify the location and format (e.g., online storage, log entries) for each required record. If the 

description changes, the owner or operator shall retain both the 

current and the most recent superseded description, as specified 

in paragraph (h)(1)(vi)(D) of this section.

(C) A description, and the date, of any change to the 

monitoring system that would reasonably be expected to affect 

its ability to comply with the requirements of paragraph (h)(1) 

of this section.

(D) The owner or operator subject to paragraph 

(h)(1)(vi)(B) of this section shall retain the current 

description of the monitoring system as long as the description 

is current. The current description shall, at all times, be 

retained on-site or be accessible from a central location by 

computer or other means that provides access within 2 hours 

after a request. The owner or operator shall retain all 

superseded descriptions for at least 5 years after the date of 

their creation. Superseded descriptions shall be retained on-
Page 233 of 262

site (or accessible from a central location by computer or other 

means that provides access within 2 hours after a request) for 

at least 6 months after their creation. Thereafter, superseded 

descriptions may be stored off-site.

(2) If an owner or operator has elected to implement the 

requirements of paragraph (h)(1) of this section for a monitored 

parameter with respect to an item of equipment and a period of 6 

consecutive months has passed without an excursion as defined in 

paragraph (h)(2)(iv) of this section, the owner or operator is 

no longer required to record the daily average value, for any 

operating day when the daily average is less than the maximum, 

or greater than the minimum established limit. With approval by 

the Administrator, monitoring data generated prior to the 

compliance date of this subpart shall be credited toward the 

period of 6 consecutive months, if the parameter limit and the 

monitoring accomplished during the period prior to the 

compliance date was required and/or approved by the 

Administrator.

(i) If the owner or operator elects not to retain the daily 

average values, the owner or operator shall notify the 

Administrator in the next Periodic Report. The notification 

shall identify the parameter and unit of equipment.

(ii) If, on any operating day after the owner or operator 

has ceased recording daily average values as provided in 
Page 234 of 262

paragraph (h)(2) of this section, there is an excursion as 

defined in paragraph (h)(2)(iv) of this section, the owner or 

operator shall immediately resume retaining the daily average 

value for each operating day and shall notify the Administrator 

in the next Periodic Report. The owner or operator shall 

continue to retain each daily average value until another period 

of 6 consecutive months has passed without an excursion as 

defined in paragraph (h)(2)(iv) of this section.

(iii) The owner or operator shall retain the records 

specified in paragraph (h)(1) of this section, for the duration 

specified in this paragraph (h) of this section. For any 

calendar week, if compliance with paragraphs (h)(1)(i) through 

(iv) of this section does not result in retention of a record of 

at least one occurrence or measured parameter value, the owner 

or operator shall record and retain at least one parameter value 

during a period of operation other than a start-up, shutdown, or 

malfunction.

(iv) For the purposes of this paragraph (h) of this 

section, an excursion means that the daily average of monitoring 

data for a parameter is greater than the maximum, or less than 

the minimum established value, except as provided in paragraphs 

(h)(2)(iv)(A) and (B) of this section.

(A) The daily average value during any startup, shutdown, 

or malfunction shall not be considered an excursion for purposes 
Page 235 of 262

of paragraph (h)(2) of this section, if the owner or operator 

operates the source during such periods in accordance with 

§63.6(e)(1).

(B) An excused excursion, as described in §63.1438(g), 

shall not be considered an excursion for the purposes of 

paragraph (h)(2) of this section.

Table 1 of Subpart PPP of Part 63—Applicability of General 

Provisions to Subpart PPP Affected Sources

Reference

Applies 

to

subpart 

PPP Explanation

63.1(a)(1) Yes §63.1423 specifies definitions in 

addition to or that supersede 

definitions in §63.2.

63.1(a)(2) Yes.

63.1(a)(3) Yes §63.1422(f) through (k) of this subpart 

and §63.160(b) identify those standards 

which overlap with the requirements of 

subparts PPP and H and specify how 

compliance shall be achieved.

63.1(a)(4) Yes Subpart PPP (this table) specifies the 

applicability of each paragraph in 

subpart A to subpart PPP.

63.1(a)(5) No Reserved.

63.1(a)(6)–(8) Yes.

63.1(a)(9) No. Reserved.

63.1(a)(6) Yes.

63.1(a)(7)-(9) No Reserved.

63.1(a)(10) Yes.

63.1(a)(11) Yes.

63.1(a)(12)–(14) Yes.
Page 236 of 262

63.1(b)(1) No §63.1420(a) contains specific 

applicability criteria.

63.1(b)(2) Yes.

63.1(b)(3) Yes.

63.1(c)(1) Yes Subpart PPP (this table) specifies the 

applicability of each paragraph in 

subpart A to subpart PPP.

63.1(c)(2) No Area sources are not subject to subpart 

PPP.

63.1(c)(3) No Reserved.

63.1(c)(4) YesNo. Reserved.

63.1(c)(5) Yes Except that affected sources are not 

required to submit notifications 

overridden by this table.

63.1(d) No Reserved.

63.1(e) Yes.

63.2 Yes §63.1423 specifies those subpart A 

definitions that apply to subpart PPP.

63.3 Yes.

63.4(a)(1)–(3) Yes.

63.4(a)(4) No Reserved.

63.4(a)(5) Yes.

63.4(b) Yes.

63.4(c) Yes.

63.5(a)(1) Yes Except the terms “source” and 

“stationary source” should be 

interpreted as having the same meaning 

as “affected source.”

63.5(a)(2) Yes.

63.5(b)(1) Yes Except §63.1420(g) defines when 

construction or reconstruction is 

subject to new source standards.

63.5(b)(2) No Reserved.

63.5(b)(3) Yes.
Page 237 of 262

63.5(b)(4) Yes Except that the initial notification 

requirements in §63.1439(e)(3) shall 

apply instead of the requirements in 

§63.9(b).

63.5(b)(5) Yes.

63.5(b)(6) Yes Except that §63.1420(g) defines when 

construction or reconstruction is 

subject to the new source standards.

63.5(c) No Reserved.

63.5(d)(1)(i) Yes.

63.5(d)(1)(ii) Yes Except that §63.5(d)(1)(ii)(H) does not 

apply.

63.5(d)(1)(iii) No §63.1439(e)(5) and §63.1434(e) specify 

notification of compliance status 

requirements.

63.5(d)(2) No.

63.5(d)(3) Yes Except §63.5(d)(3)(ii) does not apply, 

and equipment leaks subject to §63.1434 

are exempt.

63.5(d)(4) Yes.

63.5(e) Yes.

63.5(f)(1) Yes.

63.5(f)(2) Yes Except that where §63.9(b)(2) is 

referred to, the owner or operator need 

not comply.

63.6(a) Yes.

63.6(b)(1) Yes.

63.6(b)(2) Yes.

63.6(b)(3) Yes.

63.6(b)(4) Yes.

63.6(b)(5) Yes.

63.6(b)(6) No Reserved.

63.6(b)(7) No.

63.6(c)(1) Yes §63.1422 specifies the compliance date.
Page 238 of 262

63.6(c)(2) No.

63.6(c)(3) No Reserved.

63.6(c)(4) No Reserved.

63.6(c)(5) Yes.

63.6(d) No Reserved.

63.6(e) Yes Except as otherwise specified for 

individual paragraphs (below), and 

§63.6(e) does not apply to Group 2 

emission points.

63.6(e)(1)(i) No This is addressed bySee §63.1420(h)(4)

for general duty requirement.

63.6(e)(1)(ii) YesNo.

63.6(e)(1)(iii) Yes.

63.6(e)(2) Yes.

63.6(e)(3) No.

63.6(e)(3)(i) Yes For equipment leaks (subject to 

§63.1434), the start-up, shutdown, and 

malfunction plan requirement of 

§63.6(e)(3)(i) is limited to combustion, 

recovery, or recapture devices and is 

optional for other equipment. The startup, shutdown, and malfunction plan may 

include written procedures that identify 

conditions that justify a delay of 

repair.a

63.6(e)(3)(i)(A) Yes This is also addressed by 

§63.1420(h)(4).

63.6(e)(3)(i)(B) Yes.

63.6(e)(3)(i)(C) Yes.

63.6(e)(3)(ii) Yes.

63.6(e)(3)(iii) No Recordkeeping and reporting are 

specified in §63.1439(b)(1).

63.6(e)(3)(iv) No Recordkeeping and reporting are 

specified in §63.1439(b)(1).

63.6(e)(3)(v) No Requirement is specified in 

§63.1439(b)(1).
Page 239 of 262

63.6(e)(3)(vi) Yes.

63.6(e)(3)(vii) Yes.

63.6(e)(3)(vii) 

(A)

Yes.

63.6(e)(3)(vii) 

(B)

Yes Except the plan shall provide for 

operation in compliance with 

§63.1420(i)(4).

63.6(e)(3)(vii) 

(C)

Yes.

63.6(e)(3)(viii) Yes.

63.6(e)(3)(ix) Yes.

63.6(f)(1) YesNo.

63.6(f)(2) Yes Except 63.7(c), as referred to in 

§63.6(f)(2)(iii)(D) does not apply, and 

except that §63.6(f)(2)(ii) does not 

apply to equipment leaks subject to 

§63.1434.

63.6(f)(3) Yes.

63.6(g) Yes.

63.6(h) No Subpart PPP does not require opacity and 

visible emission standards.

63.6(i)(1) Yes.

63.6(i)(2) Yes.

63.6(i)(3) Yes.

63.6(i)(4)(i)(A) Yes.

63.6(i)(4)(i)(B) No Dates are specified in §63.1422(e) and 

§63.1439(e)(4)(i) for all emission 

points except equipment leaks, which are 

covered under §63.182(a)(6)(i).

63.6(i)(4)(ii) No.

63.6(i)(5)–(14) Yes.

63.6(i)(15) No Reserved.

63.6(i)(16) Yes.

63.6(j) Yes.
Page 240 of 262

63.7(a)(1) Yes.

63.7(a)(2) No §63.1439(e) (5) and (6) specify the 

submittal dates of performance test 

results for all emission points except 

equipment leaks; for equipment leaks, 

compliance demonstration results are 

reported in the Periodic Reports.

63.7(a)(3) Yes.

63.7(b) No §63.1437(a)(4) specifies notification 

requirements.

63.7(c) No Except if the owner or operator chooses 

to submit an alternative nonopacity 

emission standard for approval under 

§63.6(g).

63.7(d) Yes.

63.7(e)(1) YesNo Except that all performance tests shall 

be conducted during worst case operating 

conditions.See §63.1437(a).

63.7(e)(2) Yes.

63.7(e)(3) No Subpart PPP specifies requirements.

63.7(e)(4) Yes.

63.7(f) Yes Since a site-specific test plan is not 

required, the notification deadline in 

§63.7(f)(2)(i) shall be 60 days prior to 

the performance test, and in §63.7(f)(3) 

approval or disapproval of the 

alternative test method shall not be 

tied to the site-specific test plan.

63.7(g) Yes Except the notification of compliance 

status report requirements in 

§63.1439(e)(5) shall apply instead of 

those in §63.9(h). In addition, 

equipment leaks subject to §63.1434 are 

not required to conduct performance 

tests.

63.7(h) Yes Except §63.7(h)(4)(ii) is not 

applicable, since the site-specific test 

plans in §63.7(c)(2) are not required.

63.8(a)(1) Yes.
Page 241 of 262

63.8(a)(2) No.

63.8(a)(3) No Reserved.

63.8(a)(4) Yes.

63.8(b)(1) Yes.

63.8(b)(2) No Subpart PPP specifies locations to 

conduct monitoring.

63.8(b)(3) Yes.

63.8(c)(1) Yes.

63.8(c)(1)(i) YesNo.

63.8(c)(1)(ii) No For all emission points except equipment 

leaks, comply with §63.1439(b)(1)(i)(B); 

for equipment leaks, comply with 

§63.181(g)(2)(ii).

63.8(c)(1)(iii) YesNo.

63.8(c)(2) Yes.

63.8(c)(3) Yes.

63.8(c)(4) No §63.1438 specifies monitoring 

requirements; not applicable to 

equipment leaks, because §63.1434 does 

not require continuous monitoring 

systems.

63.8(c)(5)–(8) No.

63.8(d) No.

63.8(e) No.

63.8(f)(1)–(3) Yes.

63.8(f)(4)(i) Yes Except the timeframe for submitting 

request is specified in §63.1439(f) or 

(g); not applicable to equipment leaks, 

because §63.1434 (through subpart H of 

this part) specifies acceptable 

alternative methods.

63.8(f)(4)(ii) Yes.

63.8(f)(4)(iii) Yes.

63.8(f)(5)(i) Yes.

63.8(f)(5)(ii) No.
Page 242 of 262

63.8(f)(5)(iii) Yes.

63.8(f)(6) No Subpart PPP does not require CEMs.

63.8(g) No Data reduction procedures specified in 

§63.1439(d) and (h); not applicable to 

equipment leaks.

63.9(a) Yes.

63.9(b) No The initial notification requirements 

are specified in §63.1439(e)(3).

63.9(c) Yes.

63.9(d) Yes.

63.9(e) No §63.1437(a)(4) specifies notification 

deadline.

63.9(f) No Subpart PPP does not require opacity and 

visible emission standards.

63.9(g) No.

63.9(h) No §63.1439(e)(5) specifies notification of 

compliance status requirements.

63.9(i) Yes.

63.9(j) No.

63.10(a) Yes.

63.10(b)(1) No §63.1439(a) specifies record retention 

requirements.

63.10(b)(2) No Subpart PPP specifies recordkeeping 

requirements.

63.10(b)(3) Yes.

63.10(c) No §63.1439 specifies recordkeeping 

requirements.

63.10(d)(1) Yes.

63.10(d)(2) No §63.1439(e)(5) and (6) specify 

performance test reporting requirements; 

not applicable to equipment leaks.

63.10(d)(3) No Subpart PPP does not require opacity and 

visible emission standards.

63.10(d)(4) Yes.
Page 243 of 262

63.10(d)(5) No See §63.1439(b)(1)(ii) for malfunction 

reporting requirements.

63.10(d)(5)(i) Yes Except that reports required by 

§63.10(d)(5)(i) shall be submitted at 

the same time as Periodic Reports 

specified in §63.1439(e)(6). The startup, shutdown, and malfunction plan, and 

any records or reports of start-up, 

shutdown, and malfunction do not apply 

to Group 2 emission points.

63.10(d)(5)(ii) No.

63.10(e) No §63.1439 specifies reporting 

requirements.

63.10(f) Yes.

63.11 Yes.

63.12 Yes Except that the authority of §63.177 

(for equipment leaks) will not be 

delegated to States.

63.13–63.15 Yes.

aThe plan, and any records or reports of start-up, shutdown, and 

malfunction do not apply to Group 2 emission points.

Table 2 of Subpart PPP of Part 63—Applicability of General HON 

Provisions to Subpart PPP Affected Sources

Reference

Applies 

to 

subpart 

PPP Explanation

Applicable 

section of 

subpart PPP

Subpart F:

63.100 No

63.101 Yes Several definitions from 

63.101 are referenced at 

63.1423

63.1423.

63.102–

63.103

No

63.104 Yes With the differences noted in 

63.1435(b) through (d)

63.1435.
Page 244 of 262

63.105 Yes With the differences noted in 

63.1433(b)

63.1433.

63.106 No

63.107 No

Subpart G:

63.110 No

63.111 Yes Several definitions from 

63.111 are incorporated by 

reference into 63.1423

63.1423.

63.112 No

63.113–

63.118

Yes For THF facilities, with the 

differences noted in 

63.1425(f)(1) through (f)(10)

63.1425.

No For epoxide facilities, 

except that 63.115(d) is used 

for TRE determinations

63.1428.

63.119–

63.123

Yes With the differences noted in 

63.1432(b) through 63.1432(p)

63.1432.

63.124–

63.125

No Reserved

63.126–

63.130

No

63.131 No Reserved

63.132–

63.147

Yes With the differences noted in 

63.1433(a)(1) through 

63.1433(a)(19)

63.1433.

63.148–

63.149

Yes With the differences noted in 

63.1432(b) through 63.1432(p) 

and 63.1433(a)(1) through 

63.1433(a)(19)

63.1432 and 

63.1433.

63.150 No

63.151–

63.152

No

63.153 No 63.1421.

Subpart H:

63.160– Yes Subpart PPP affected sources 63.1434.
Page 245 of 262

63.182 shall comply with all 

requirements of subpart H, 

with the differences noted in 

63.1422(d), 63.1422(h), and 

63.1434(b) through (g)

Subpart U:

63.480–

63.487

No

63.488 Yes Portions of 63.488(b) and (e) 

are cross-referenced in 

subpart PPP.

63.489–

63.506

No

Table 3 to Subpart PPP of Part 63—Group 1 Storage Vessels at 

Existing and New Affected Sources

Vessel capacity

(cubic meters)

Vapor Pressurea

(kilopascals)

75 ≤ capacity < 151 ≥ 13.1

capacity ≥ 151 ≥ 5.2

aMaximum true vapor pressure of total organic HAP at storage 

temperature.

Table 4 to Subpart PPP of Part 63—Known Organic HAP From 

Polyether Polyol Products

Organic HAP/chemical name

[CAS No.]

1,3 Butadiene

(106990)

Epichlorohydrin

(106898)

Ethylene Oxide

(75218)

n-Hexane

(110543)
Page 246 of 262

Methanol

(67561)

Propylene Oxide

(75569)

Toluene

(108883)

CAS No. = Chemical Abstracts Service Registry Number.

Table 5 to Subpart PPP of Part 63—Process Vents From Batch Unit 

Operations—Monitoring, Recordkeeping, and Reporting Requirements

Control technique

Parameter to be 

monitored

Recordkeeping and 

reporting requirements 

for monitored parameters

Thermal 

Incinerator

Firebox temperaturea 1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average firebox 

temperature measured 

during the performance 

test—NCS.c

3. Record the daily 

average firebox 

temperature as specified 

in §63.1429.

4. Report all daily 

average temperatures 

that are below the 

minimum operating 

temperature established 

in the NCS or operating 

permit and all instances 

when monitoring data are 

not collected—PR.d,e

Catalytic 

Incinerator

Temperature upstream 

and downstream of the 

catalyst bed

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average upstream and 

downstream temperatures 

and the average 
Page 247 of 262

temperature difference 

across the catalyst bed 

measured during the 

performance test—NCS.c

3. Record the daily 

average upstream 

temperature and 

temperature difference 

across catalyst bed as 

specified in §63.1429.

4. Report all daily 

average upstream 

temperatures that are 

below the minimum 

upstream temperature 

established in the NCS 

or operating permit—

PR.d,e

5. Report all daily 

average temperature 

differences across the 

catalyst bed that are 

below the minimum 

difference established 

in the NCS or operating 

permit—PR.d,e

6. Report all instances 

when monitoring data are 

not collected.e

Boiler or Process 

Heater with a 

design heat input 

capacity less than 

44 megawatts and 

where the process 

vents are not

introduced with or 

used as the 

primary fuel

Firebox temperaturea 1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average firebox 

temperature measured 

during the performance 

test—NCSc

3. Record the daily 

average firebox 

temperature as specified 

in §63.1429.d

4. Report all daily 

average temperatures 

that are below the 

minimum operating 
Page 248 of 262

temperature established 

in the NCS or operating 

permit and all instances 

when monitoring data are 

not collected—PR.d,e

Flare Presence of a flame 

at the pilot light

1. Hourly records of 

whether the monitor was 

continuously operating 

during batch emission 

episodes selected for 

control and whether a 

flame was continuously 

present at the pilot 

light during each hour.

2. Record and report the 

presence of a flame at 

the pilot light over the 

full period of the 

compliance 

determination—NCS.c

3. Record the times and 

durations of all periods 

during batch emission 

episodes when all flames 

at the pilot light of a 

flare are absent or the 

monitor is not 

operating.

4. Report the times and 

durations of all periods 

during batch emission 

episodes selected for 

control when all flames 

at the pilot light of a 

flare are absent—Pr.d

Absorberf Liquid flow rate into 

or out of the 

scrubber, or the 

pressure drop across 

the scrubber

1. Records every 15 

minutes, as specified in 

§63.1429.b

2. Record and report the 

average liquid flow rate 

into or out of the 

scrubber, or the 

pressure drop across the 

scrubber, measured 
Page 249 of 262

during the performance 

test—NCS.

3. Record the liquid 

flow rate into or out of 

the scrubber, or the 

pressure drop across the 

scrubber, every 15 

minutes, as specified in 

§63.1429.

4. Report all scrubber 

flow rates or pressure 

drop values that are 

below the minimum 

operating value 

established in the NCS 

or operating permit and 

all instances when 

monitoring data are not 

collected—PR.d,e

pH of the scrubber 1. Once daily records as 

specified in §63.1429.b

2. Record and report the 

average pH of the 

scrubber effluent 

measured during the 

performance test—NCS.c

3. Record at least once 

daily the pH of the 

scrubber effluent.

4. Report all pH 

scrubber effluent 

readings out of the 

range established in the 

NCS or operating permit 

and all instances when 

monitoring data are not 

collected—PR.d,e If a 

base absorbent is used, 

report all pH values 

that are below the 

minimum operating 

values. If an acid 

absorbent is used, 
Page 250 of 262

report all pH values 

that are above the 

maximum operating 

values.

Condenserf Exit (product side) 

temperature

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average exit temperature 

measured during the 

performance test—NCS.

3. Record the daily 

average exit temperature 

as specified in 

§63.1429.

4. Report all daily 

average exit 

temperatures that are 

above the maximum 

operating temperature 

established in the NCS 

or operating permit and 

all instances when 

monitoring data are not 

collected—PR.d,e

Carbon Adsorberf Total regeneration 

stream mass or 

volumetric flow 

during carbon bed 

regeneration 

cycle(s), and

1. Record of total 

regeneration stream mass 

or volumetric flow for 

each carbon bed 

regeneration cycle.

2. Record and report the 

total regeneration 

stream mass or

volumetric flow during 

each carbon bed 

regeneration cycle 

during the performance 

test—NCS.c

3. Report all carbon bed 

regeneration cycles when 

the total regeneration 

stream mass or 

volumetric flow is above 

the maximum flow rate 
Page 251 of 262

established in the NCS 

or operating permit—

PR.d,e

Temperature of the 

carbon bed after 

regeneration and 

within 15 minutes of 

completing any 

cooling cycle(s)

1. Record the 

temperature of the 

carbon bed after each 

regeneration and within 

15 minutes of completing 

any cooling cycle(s).

2. Record and report the 

temperature of the 

carbon bed after each 

regeneration and within 

15 minutes of completing 

any cooling cycle(s) 

measured during the 

performance test—NCS.c

3. Report all carbon bed 

regeneration cycles when 

the temperature of the 

carbon bed after 

regeneration, or within 

15 minutes of completing 

any cooling cycle(s), is 

above the maximum 

temperature established 

in the NCS or operating 

permit—PR.d,e

Absorber, 

Condenser, and 

Carbon Adsorber 

(as an alternative 

to the above)

Concentration level 

or reading indicated 

by an organic 

monitoring device at 

the outlet of the 

recovery device

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average concentration 

level or reading 

measured during the 

performance test—NCS.

3. Record the daily 

average concentration 

level or reading as 

specified in §63.1429.

4. Report all daily 

average concentration 

levels or readings that 

are above the maximum 

concentration or reading 
Page 252 of 262

established in the NCS 

or operating permit and 

all instances when 

monitoring data are not 

collected—PR.d,e

All Combustion, 

recovery, or 

recapture devices

Diversion to the 

atmosphere from the 

combustion, recovery, 

or recapture device 

or

1. Hourly records of 

whether the flow 

indicator was operating 

during batch emission 

episodes selected for 

control and whether a 

diversion was detected 

at any time during the 

hour, as specified in 

§63.1429.

2. Record and report the 

times of all periods 

during batch emission 

episodes selected for 

control when emissions 

are diverted through a 

bypass line, or the flow 

indicator is not 

operating—PR.d

Monthly inspections 

of sealed valves

1. Records that monthly 

inspections were 

performed as specified 

in §63.1429.

2. Record and report all 

monthly inspections that 

show that valves are in 

the diverting position 

or that a seal has been 

broken—PR.d

ECO Time from the end of 

the epoxide feed, or 

the epoxide partial 

pressure in the 

reactor or direct 

measurement of 

epoxide concentration 

in the reactor liquid 

at the end of the ECO

1. Records at the end of 

each batch, as specified 

in §63.1427(i).

2. Record and report the 

average parameter value 

of the parameters 

chosen, measured during 

the performance test.

3. Record the batch 

cycle ECO duration, 

epoxide partial 
Page 253 of 262

pressure, or epoxide 

concentration in the 

liquid at the end of the 

ECO

4. Report all batch 

cycle parameter values 

outside of the ranges 

established in 

accordance with 

§63.1427(i)(3) and all 

instances when 

monitoring data were not 

collected—PR.d,e

aMonitor may be installed in the firebox or in the ductwork 

immediately downstream of the firebox before any substantial 

heat exchange is encountered.

b“Continuous records” is defined in §63.111.

cNCS = Notification of Compliance Status described in §63.1429.

dPR = Periodic Reports described in §63.1429.

eThe periodic reports shall include the duration of periods when 

monitoring data are not collected as specified in §63.1439.

fAlternatively, these devices may comply with the organic 

monitoring device provisions listed at the end of this table.

Table 6 to Subpart PPP of Part 63—Process Vents From Continuous 

Unit Operations—Monitoring, Recordkeeping, and Reporting 

Requirements

Control technique

Parameter to be 

monitored

Recordkeeping and 

reporting requirements 

for monitored parameters

Thermal Incinerator Firebox 

temperaturea

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average firebox 

temperature measured 

during the performance 

test—NCS.c

3. Record the daily 
Page 254 of 262

average firebox 

temperature for each 

operating day.

4. Report all daily 

average temperatures 

that are below the 

minimum operating 

temperature established 

in the NCS or operating 

permit and all instances 

when sufficient 

monitoring data are not 

collected—PR.d,e

Catalytic Incinerator Temperature 

upstream and 

downstream of the 

catalyst bed

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average upstream and 

downstream temperatures 

and the average 

temperature difference 

across the catalyst bed 

measured during the 

performance test—NCSc

3. Record the daily 

average upstream 

temperature and 

temperature difference 

across catalyst bed for 

each operating day.

4. Report all daily 

average upstream 

temperatures that are 

below the minimum 

upstream temperature 

established in the NCS 

or operating permit—

PR.d,e

5. Report all daily 

average temperature 

differences across the 

catalyst bed that are 

below the minimum 

difference established 

in the NCS or operating 
Page 255 of 262

permit—PR.d,e

6. Report all operating 

days when insufficient 

monitoring data are 

collected.e

Boiler or Process 

Heater with a design 

heat input capacity 

less than 44 

megawatts and where 

the process vents are 

not introduced with 

or used as the 

primary fuel

Firebox 

temperaturea

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

average firebox 

temperature measured 

during the performance 

test—NCSc

3. Record the daily 

average firebox 

temperature for each 

operating day.d

4. Report all daily 

average temperatures 

that are below the 

minimum operating 

temperature established 

in the NCS or operating 

permit and all instances 

when insufficient 

monitoring data are 

collected—PR.d,e

Flare Presence of a 

flame at the pilot 

light

1. Hourly records of 

whether the monitor was 

continuously operating 

and whether a flame was 

continuously present at 

the pilot light during 

each hour.

2. Record and report the 

presence of a flame at 

the pilot light over the 

full period of the 

compliance 

determination—NCS.c

3. Record the times and 

durations of all periods 

when all flames at the 

pilot light of a flare 

are absent or the 
Page 256 of 262

monitor is not 

operating.

4. Report the times and 

durations of all periods 

when all flames at the 

pilot light of a flare 

are absent—Pr.d

Absorberf Exit temperature 

of the absorbing 

liquid, and

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

exit temperature of the 

absorbing liquid 

averaged over the full 

period of the TRE 

determination—NCS.c

3. Record the daily 

average exit temperature 

of the absorbing liquid 

for each operating day.

4. Report all the daily 

average exit 

temperatures of the 

absorbing liquid that 

are below the minimum 

operating value 

established in the NCS 

or operating—PR.d,e

Exit specific 

gravity for the 

absorbing liquid

1. Continuous records as

specified in §63.1429.b

2. Record and report the 

exit specific gravity 

averaged over the full 

period of the TRE 

determination—NCS.

3. Record the daily 

average exit specific 

gravity for each 

operating day.

4. Report all daily 

average exit specific 

gravity values that are 

below the minimum 

operating value 
Page 257 of 262

established in the NCS 

or operating—PR.d,e

Condenserf Exit (product 

side) temperature

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

exit temperature 

averaged over the full

period of the TRE 

determination—NCS.

3. Record the daily 

average exit temperature 

for each operating day.

4. Report all daily 

average exit 

temperatures that are 

above the maximum 

operating temperature 

established in the NCS 

or operating—PR.d,e

Carbon Adsorberf Total regeneration 

stream mass or 

volumetric flow 

during carbon bed 

regeneration 

cycle(s), and

1. Record of total 

regeneration stream mass 

or volumetric flow for 

each carbon bed 

regeneration cycle.

2. Record and report the 

total regeneration 

stream mass or 

volumetric flow during 

each carbon bed 

regeneration cycle 

during the period of the 

TRE determination—NCS.c

3. Report all carbon bed 

regeneration cycles when 

the total regeneration 

stream mass or 

volumetric flow is above 

the maximum flow rate 

established in the NCS 

or operating permit—

PR.d,e

Temperature of the 

carbon bed after 

1. Record the 

temperature of the 
Page 258 of 262

regeneration and 

within 15 minutes 

of completing any 

cooling cycle(s)

carbon bed after each 

regeneration and within 

15 minutes of completing 

any cooling cycle(s).

2. Record and report the 

temperature of the 

carbon bed after each 

regeneration during the 

period of the TRE 

determination—NCSc

3. Report all carbon bed 

regeneration cycles when 

the temperature of the 

carbon bed after 

regeneration is above 

the maximum temperature 

established in the NCS 

or operating permit—

PR.d,e

Absorber, Condenser, 

and Carbon Adsorber 

(as an alternative to 

the above)

Concentration 

level or reading 

indicated by an 

organic monitoring 

device at the 

outlet of the 

recovery device

1. Continuous records as 

specified in §63.1429.b

2. Record and report the 

concentration level or 

reading averaged over 

the full period of the 

TRE determination—NCS.

3. Record the daily 

average concentration 

level or reading for 

each operating day.

4. Report all daily 

average concentration 

levels or readings that 

are above the maximum 

concentration or reading 

established in the NCS 

or operating—PR.d,e

All Combustion, 

recovery, or 

recapture devices

Diversion to the 

atmosphere from 

the combustion, 

recovery, or 

recapture 

device or

1. Hourly records of 

whether the flow 

indicator was operating 

and whether a diversion 

was detected at any time 

during each hour.

2. Record and report the 
Page 259 of 262

times of all periods 

when the vent stream is 

diverted through a 

bypass line, or the flow 

indicator is not 

operating—PR.d

Monthly 

inspections of 

sealed valves

1. Records that monthly 

inspections were 

performed as specified 

in §63.1429.

2. Record and report all 

monthly inspections that 

show that valves are in 

the diverting position 

or that a seal has been 

broken—PR.d

aMonitor may be installed in the firebox or in the ductwork 

immediately downstream of the firebox before any substantial 

heat exchange is encountered.

b“Continuous records” is defined in §63.111.

cNCS = Notification of Compliance Status described in §63.1429.

dPR = Periodic Reports described in §63.1429.

eThe periodic reports shall include the duration of periods when 

monitoring data are not collected as specified in §63.1439.

fAlternatively, these devices may comply with the organic 

monitoring device provisions listed at the end of this table.

Table 7 to Subpart PPP of Part 63— Operating Parameters For Which 

Monitoring Levels Are Required to be Established For Process 

Vent StreamsProcess Vents From Continuous Unit Operations—

Monitoring, Recordkeeping, and Reporting Requirements

Control 

technique Parameters to be monitored

Established operating 

parameter(s)

Thermal 

incinerator

Firebox temperature Minimum temperature.

Catalytic

incinerator

Temperature upstream and 

downstream of the catalyst 

Minimum upstream 

temperature; and 
Page 260 of 262

bed minimum temperature 

difference across the 

catalyst bed.

Boiler or 

process 

heater

Firebox temperature Minimum temperature.

Absorber Liquid flow rate or 

pressure drop; and pH of 

scrubber effluent, if an 

acid or base absorbent is 

used

Minimum flow rate or 

pressure drop; and 

maximum pH if an acid 

absorbent is used, or 

minimum pH if a base 

absorbent is used.

Condenser Exit temperature Maximum temperature.

Carbon 

adsorber

Total regeneration stream 

mass or volumetric flow 

during carbon bed 

regeneration cycle; and 

temperature of the carbon 

bed after regeneration (and 

within 15 minutes of 

completing any cooling 

cycle(s))

Maximum mass or 

volumetric flow; and 

maximum temperature.

Extended 

Cookout (ECO)

Time from the end of the 

epoxide feed to the end of 

the ECO, or the reactor 

epoxide partial pressure at 

the end of the ECO, or the 

epoxide concentration in 

the reactor liquid at the 

end of the ECO

Minimum duration, or 

maximum partial 

pressure at the end of 

ECO, or maximum 

epoxide concentration 

in the reactor liquid 

at the end of ECO.

Other devices 

(or as an 

alternate to 

the above).a

HAP concentration level or 

reading at outlet of device

Maximum HAP 

concentration or

reading.

aConcentration is measured instead of an operating parameter.

Table 8 to Subpart PPP of Part 63—Routine Reports Required by 

This Subpart

Reference

Description of 

report Due date
Page 261 of 262

§63.1439(b) and 

subpart A of this 

part

Refer to 

§63.1439(b), 

Table 1 of this 

subpart, and to 

subpart A of this 

part

Refer to subpart A of this 

part.

§63.1439(e)(3) Initial 

notification

New affected sources w/ 

initial start-up at least 

90 days after June 1, 

1999: submit the 

application for approval 

of construction or 

reconstruction in lieu of 

the initial notification 

report.

New affected sources w/ 

initial start-up prior to 

90 days after June 1, 

1999:by 90 days after June 

1, 1999.

§63.1439(e)(4) Precompliance 

Reporta

Existing affected sources: 

12 months prior to 

compliance date.

New affected sources: with 

the application for 

approval of construction 

or reconstruction.

§63.1439(e)(5) Notification of 

Compliance Statusb

Within 150 days after the 

compliance date.

§63.1439(e)(6) Periodic Reports Semiannually, no later 

than 60 days after the end 

of each 6-month period. 

See §63.1439(e)(6)(i) for 

the due date for this 

report.

§63.1439(e)(6)(iii) Quarterly reports 

for sources with 

excursions (upon 

request of the 

Administrator)

No later than 60 days 

after the end of each 

quarter.

§63.506(e)(7)(i) Storage Vessels 

Notification of 

Inspection

At least 30 days prior to 

the refilling of each 

storage vessel or the 
Page 262 of 262

inspection of each storage 

vessel.

aThere may be two versions of this report due at different times; 

one for equipment subject to §63.1434 and one for other emission 

points subject to this subpart.

bThere will be two versions of this report due at different 

times; one for equipment subject to §63.1434 and one for other 

emission points subject to this subpart.