OAR Box 1811 

Prepped by Keeia Richards 

Document Number: 

40) lll-A-1 

Docket Number: 

A-84-22 

Printed 10/30/2008 1:19:24 PM Sheet 40 of 82 

p.1 

- — 
P.2 

^ 

Friday 

August 29, 1986 

Part VI 

Environmental 

Protection Agency 

40 CFR Part 52 

Source Surveillance of Visible Emissions; 

Proposed Revisions of Existing Rule 
P.3 

31076 Federal Kegister / Vol. 51, No. 168 / Friday, August 29, 1986 / Proposed Rules 

ENVIRONMENTAL PROTECTION! 

<90 Cm Part 52 

[AD-FE-.L-2983-7] 

Source Suirvelllsunce ©ff Visible 

Emissions 

AGEMCV: Environmental Protection 

Agency (EPA). 

aST0®ca: Proposed revisions of existing 

rule. 

SUKOARV: The EPA proposes to 

promulgate new visible emission test 

procedures for evaluating compliance 

with opacity standards when a State 

implementation plan (SIP) does not 

contain an appropriate test method tit 

when the Administrator promulgates a 

plan for a State. Section 52.12(c) requires 

EPA to use appropriate procedures and 

test methods in 40 CFR 60 for 

enforcement of SIP requirements if the 

SIP does not specify a method. The test 

method in Part 60 for visible emission 

observations is Method 9 of Appendix 

A. This action proposes to incorporate a 

new Method, F-1, for reading visible 

emissions, for use in place of Method 9 

under appropriate circumstances, into a 

new Appendix F of Part 52. The new 

Method, F-1, provides EPA with an 

expanded array of data reduction 

procedures for various types of SIP 

opacity limitations. These procedures 

constitute the main difference between 

Methods 9 and F-1. This action is 

necessary because the current data 

reduction procedures of Method 9 may 

not adequately relate to SIP opacity 

regulations which specify no averaging 

time, or have certain data aggregation 

provisions that are not consistent with 

the data averaging procedures specified 

in Method 9. This action will provide 

EPA with visible emission test 

procedures that would be available for 

use with most SIP opacity regulations. 

Additionally the notice clarifies EPA's 

intention that evidence of violation not 

be solely limited to test results, but the 

fact that violations have occurred may 

be proven by evidence admissible under 

Federal Rules of Evidence. The EPA 

proposes to add a statement in § 52.23 

regarding this intent. No revisions to any 

SIP are required by this action. 

DATES: Comments must be submitted on 

or before October 28,1986. 

ADDRESSES: Send comments to: Central 

Docket Section (LE-131), EPA, 

Attention: Docket No. A-84-22,401M 

Street, SW., Washington, DC 20460. 

Docket No. A-84-22, containing material 

relevant to this rulemaking, is located in 

EPA's Central Docket Section, West .. . 

Tower Lobby, Gallery 1, 401M Street, 

Washington, DC 20460. The docket may 

be inspected between 8 a.m. and 4 p.m. 

on weekdays, and a reasonable fee may 

be charged for copying. 

FOR FURTHER INFORMATION ©0NTAST: 

Ted Creekmore or Joseph Sableski, 

Standards Implementation Branch, MD15, EPA, Research Triangle Park, North 

Carolina, 27711, telephone: (commercial) 

919-541-5697 or (FTS) 629-5697. 

SUPPLEMENTARY INFORMATION: 

Introduction 

The Clean Air Act (Act) includes 

requirements that EPA establish 

national ambient air quality standards 

for various pollutants which may 

reasonably be anticipated to endanger 

public health and welfare. The Act 

requires States to develop SIP's which 

include rules to control emissions of air 

pollutants. Many SIP's include 

regulations limiting emissions from 

sources by limiting visible emissions. 

The SIP's include a variety of such 

limits. The limits are generally written to 

specify a maximum opacity a source is 

allowed to emit, as determined by a 

trained observer. Some provisions limit 

opacity for a specified number of 

minutes in an hour (time exception), 

others limit it for levels as averaged 

over a specified number of minutes 

(time averaged), and others specify 

limits that are never to be exceeded 

(instantaneous limitation). Many SIP's 

do not prescribe the test methods to be 

used to determine compliance with 

opacity provisions. When EPA desires 

to enforce these regulations, 40 CFR 

52.12(c) specifies that EPA will do so 

using appropriate test methods in 40 

CFR 60, Standards of Performance for 

New Stationary Sources. The only 

general visible emission observation test 

procedure in 40 CFR 60 is Method 9 of 

Appendix A. 

Method 9 contains procedures for the 

training and certification of observers, 

field procedures for the determination of 

plume opacity, and a data reduction 

procedure. It provides a time-averaged 

data reduction technique whereby 

opacity levels are determined by 

averaging 24 consecutive opacity 

observations, each taken at 15-second 

intervals, to arrive at an average opacity 

for a 6-minute period. 

The EPA revised Method 9 on 

November 12,1974 (39 FR 39872). The 

preamble to that revision recognized 

that the data reduction techniques in 

Method 9 were not appropriate for some 

types of SIP opacity regulations. The 

preamble also stated EPA's intent to 

propose procedures to enforce SIP 

limitations not adequately addressed 

under Method 9. Such regulations 

include those with time-exception 

provisions, as well as those that specify 

averaging times of other than 6 minutes. 

Also, Method 9 did not address data 

reduction procedures for instantaneous 

limitations (sometimes called caps) on 

visible emissions which are included in 

some SIP's. 

The EPA proposes to promulgate 

explicit test procedures to determine 

compliance with SIP opacity limitations 

in a new Method, F-1, of a new 

Appendix F to Part 52. The new Method, 

F-1, provides EPA with an expanded 

array of visible emission data reduction 

procedures for various types of SIP 

opacity limitations. It will replace 

Method 9 for EPA enforcement of SIP 

opacity limitations. Method F-1 contains 

field and observer certification 

procedures that are identical to those of 

Method 9. The only difference between 

Method 9 and the new Method, F-1, are 

the data reduction procedures. These 

new data reduction procedures are 

appropriate for determining compliance 

with SIP regulations that contain timeexception, time-averaged (2 minutes or 

greater), and instantaneous limitations. 

The proposed data reduction procedures 

are based on a number of data sets. The 

test data and other background 

information are included in the docket. 

The proposed data reduction procedures 

are discussed in the following 

Data Reduction Procedures for TimeException Opacity Regulations 

This procedure applies to SIP 

regulations that allow a certain level of 

visible emissions to be exceeded for a 

specified period of time. Such 

regulations are often referred to as timeexception regulations. A typical timeexception repletion might provide that 

a source cannot exceed 20 percent 

opacity except for 5 minutes in any 1 

hour. The 8-minute averaging technique 

used in Method 9 may result in 

underenforcement of this type of 

regulation. Underenforcement may 

occur because some sources exhibit 

short-term peak level opacity intermixed 

with periods of no visible emissions at 

all. Thus, the opacity readings in excess 

of the standard can be effectively offset 

in the averaging of 24 consecutive 

readings by the periods of very low 

readings, resulting in an overall opacity 

value which is in compliance with the 

SIP regulation. 

Section 2.5.1 of Method F-1, "TimeException Regulations," provides for 

effective enforcement of time-exception 

provisions. It requires that readings 

above the allowable level be added 
P.4 

Register / Vol. 51, No. 168 / Friday, August 29, 1986 / .Proposed Rules 

together or "aggregated" to determine 

compliance with the exception period of 

the regulation. This is done without 

regard to any "averaging period," taken 

during the appropriate observation 

period, usually up to an hour. 

Data Reduction for Time-Averaged 

Opacity Regulations 

This data reduction procedure is very 

similar to that of Method 9 except that it 

applies to SIP regulations which specify 

averaging times different from Method 9. 

The use of a 6-minute average when the 

SIP specifies a shorter averaging time 

may result in underenforcement of SIP 

regulations in comparison with other, 

shorter averaging periods. Such 

underenforcement may occur because 

State regulations that specify averaging 

times of less than 6 minutes are better 

able to control sources with frequent 

opacity fluctuations. The less-than-6-

minute averge is a more sensitive 

indicator of short-term visible emission 

excursions above the standard which 

may not be properly reflected when 

averaged over the full 6-minute period 

as specified in Method 9. 

Under section 2.5.2 of Method F-1, 

"Time-Averaged Regulations," 

individual 15-second readings are 

averaged over the time period specified 

by the SIP or federally-promulgated 

regulation. 

Where a SIP specifies an averaging 

time of 6 minutes, the 6-minute 

averaging procedure of Method F-1 will 

be used to determine compliance with 

the standard. Section 2.5.2 also includes 

the flexibility to reduce and report 

opacity observations averaged over 

periods of 6 minutes, or greater if such 

an averaging period is specified by the 

applicable SIP. 

Data Reduction Procedures for 

Instantaneous Opacity Regulations 

The EPA will use this procedure to 

enforce SIP visible emission limitations 

that are intended by tiie State or Federal 

government as never-to-be-exceeded 

opacity limitations. The proposed 

section 2.5.3, "Instantaneous Limitation 

Regulations," specified the use of a 2-

minute averaging time for determining 

compliance with the "never-to-beexceeded" or "cap" limitation. The 2-

minute averaging time is used because it 

is consistent with acceptable accuracy 

levels for opacity observations. 

Many State regulations include twotiered opacity standards. An example of 

a two-tiered limitation is "... visible 

emissions may not exceed 20 percent 

opacity, except for 3 minutes in any 1 

hour, and may not exceed 40 percent 

opacity." The first level, 20 percent 

opacity, would be treated as a timeexception regulation, and the second 

level, 40 percent opacity, as an 

instantaneous limitation under section 

2.5.3. 

In other situations, a single opacity 

limitation has been adopted as an 

instantaneous limitation for certain 

sources under the SIP regulations. For 

either the single or two-tiered case, this 

data reduction procedure would apply if 

it was clearly the intent of the regulation 

that the opacity limitation was never to 

be exceeded. 

Procedures to Implement 40 CFR 

52.12(c) 

To test for compliance, EPA will 

select the visible emission test method 

and data reduction procedure in Part 52 

which best ensures that the SIP visible 

emission standard is being enforced in a 

manner that is as consistent as possible 

with the language originally contained 

in the rule incorporated in the federallyapproved or promulgated SIP. Absent an 

indication of State intent to the contrary, 

EPA will assume that a State intended a 

6-minute averaging time be associated 

with SIP opacity regulations which 

contain no specific reference to timeexception, time-averaging, or 

instantaneous limitations. 

Accuracy of Methods 

The accuracy of visible emission 

observations is chiefly dependent upon 

the training of the obervers and the field 

procedures utilized by the observer for 

assigning opacity values. The training, 

certification, and field procedures in this 

proposed test method, F-1, are taken 

from Reference Method 9,40 CFR Part 

60, Appendix A. These Method 9 

procedures were sustained by the Court 

of Appeals for the D.C. Circuit in 

Portland Cement v. Train 513 F.2d 506 

(D.C. Cir. 1975). 

The EPA reviewed the training and 

certification procedures and the field 

procedures of the current Method 9 

during the development of these new 

test procedures. The EPA concluded that 

these procedures remain the best 

available means of assuring the 

accuracy of visible emission 

observations. The field procedures 

reduce to the extent possible the 

potential influence of variables that 

might otherwise affect the ability of the 

observer to accurately assign opacity 

values. 

The docket, A-84-22, contains reports 

on field studies and other data which 

EPA has used to support the accuracy of 

these test procedures. This information 

indicates that in visible emission 

observations both positive and negative 

error may occur. 

A positive error occurs when an 

observer assigns an opacity value 

greater than the actual plume opacity. A 

negative error occurs when an observer 

assigns an opacity value lower than the 

actual plume opacity. 

To evalute potential errors, both 

positive and negative, a series of field 

experiments were conducted under 

controlled field conditions using light 

and dark visible plumes generated using 

a smoke generator, equipped with a 

transmissometer meeting the 

specifications of Method 9. During these 

evaluation tests, panels of qualified 

observers (certified by Method 9 

procedures) read the generated plumes 

in 5 percent opacity increments and at 

15-second intervals. The data were 

reduced for time-averaged regulations 

by averaging for varying lengths of time, 

and for time-exception regulations by 

aggregating the data over the time 

period of each reading. Data from earlier 

field trials also were evaluated. 

Observer measurements were then 

compared to the reference values 

measured by the transmissometer in the 

stack of the smoke generator. 

Docket A-84-22 contains a detailed 

discussion of error in opacity readings. 

From the data in the docket, EPA has 

determined the error probabilities for 

these test procedures as used for 

determining compliance with opacity 

standards. These studies demonstrate 

conclusively that opacity readings taken 

in accordance with the test procedures 

prescribed in this proposal reflect an 

overall negative bias; i.e., the observers 

are more likely to assign opacity values 

that are below, rather than above the 

actual opacity value. The field studies 

conducted by EPA demonstrate that 

there is about a 60-70 percent 

probability of no positive error for 

opacity readings taken under the timeaveraged and time-exception test 

procedures, respectively. 

Tables 1-5 in the introduction to the 

proposed regulations indicate the 

probability of the existence of various 

levels of maximum potential positive 

error for time-averaged procedures, and 

were derived by comparing observed 

opacity with the measured opacity. The 

tables present data for 2- to 6-minute 

averaging times. 

Table 6 in the introduction to the 

proposed regulation indicates the range 

of observer errors which occurred in 

determining the duration of visible 

emissions using time-exception test 

procedures and was derived by 

comparing time calculated from the 

observer's readings with the measured 

value. A combination of opacity error 

and time error was determined to be the 
P.5 

31078 Federal Register / Vol. 51, No. 168 / Friday, August 29, 1986 / Proposed Rules 

most practical way of explaining 

accuracy for this method. 

Method F-1 in Appendix F of Part 52 

will be used by EPA to assess 

compliance with SIP opacity regulations 

where a SIP does not contain an 

applicable opacity test method or where 

the Administrator promulgates a SIP 

opacity regulation. When EPA seeks to 

enforce compliance with SIP opacity 

regulations, test results which exceed 

the applicable standard will be used as 

evidence of a violation in Federal 

judicial action and in EPA 

administrative actions. 

All reference method test results will 

be considered by EPA as competent 

evidence of compliance or violation. The 

method error analysis will be 

considered by EPA along with other 

relevant factors in determining whether 

the test results establish compliance 

with, or a violation of, an opacity 

standard. 

Application of Method F-1 to Fugitive 

Dust 

The EPA believes that visible 

emission surveillance based on Method 

F-1 is appropriate for determining 

compliance of fugitive process dust 

sources with State emission regulations. 

For many years Method 9 has been used 

to measure the opacity of these sources 

in new source performance standards 

(NSPS). The EPA also believes that 

Method F-1 can be applied to fugitive 

dust emissions from nonprocess sources 

such as roads and parking lots. The EPA 

is currently developing a more complete 

record to support application of this 

method to nonprocess fugitives. The 

EPA is also considering the addition of 

clarifying language to Method F-1 that 

will assure its applicability to State 

regulations governing nonprocess 

fugitive sources. For example, certain 

existing State regulations for limiting 

visible emissions from roads and lots 

specify the conditions and points in the 

plume under which observation will be 

made. The regulations address such 

conditions as intermixing of plumes and 

unusual conditions (such as a broken 

cement bag on the pavement). The 

regulations also address points in the 

plume such as how high above the 

surface the readers should make 

observations. 

If at the close of this rulemaking EPA 

decides, as it now proposes, to use 

Method F-1 for nonprocess fugitives, 

EPA will consider changing the terms 

governing observation techniques in the 

test method itself to account for physical 

differences between testing process and 

nonprocess fugitive sources. The EPA 

solicits comments on whether these 

kinds of adjustments to Method F-1 

would be necessary or appropriate. 

The Federal Rules of Evidence 

This action proposes to revise 40 CFR 

52.23, "Violation and Enforcement," to 

clarify that the promulgation of test 

methods in Parts 52 and 60 are not 

intended to limit the use of evidence 

that would otherwise be admissible 

under the Federal Rules of Evidence. 

The Federal Rules of Evidence govern 

proceedings in the courts of the United 

States and before United States 

magistrates to the extent and with the 

exceptions stated in Rule 1101 (Fed. R. 

Evid. 101). Section 113(b)(5) of the Act 

provides that". . . [a]ny action under 

this subsection may be brought in the 

district court in which the defendant 

resides or has his principal place of 

business . . ." [42 U.S.C. 7413(b)(5)]. All 

civil enforcement actions brought by 

EPA under the Act are thus subject to 

the Federal Rules of Evidence. Under 

the Federal Rules of Evidence all 

relevant evidence is admissible, subject 

to limited exceptions (Fed. R. Evid. 402 

advisory committee note). The court has 

the ultimate authority to decide any 

issue involving the admissibility of 

evidence. 

The EPA never intended the 

promulgation of test methods to limit the 

admissibility of other forms of evidence. 

Thus, expert testimony may be used, for 

example, by the government to prove 

violations or to present evidence of the 

extent to which pollution control 

technology is applied. Admissions may 

be used as evidence of violation and of 

actions or positions which have been 

taken by the source. The issue of 

whether expert testimony or admissions 

by party opponents or any other 

evidence is admissible is to be decided 

by the court. Thus, we are proposing 

language to the Code of Federal 

Regulations that retains judicial 

flexibility to consider admitting 

competent evidence such as expert 

testimony and admissions by party 

opponents. 

Regulatory Impact 

Under Executive Order 12291, EPA 

must judge whether a regulation is 

"major" and therefore subject to the 

requirement of a regulatory impact 

analysis. This proposed regulation is not 

a major rule because it will not result in 

an effect on the economy of $100 million 

or more, nor will it result in an increase 

in costs or prices to industry. There will 

be no adverse impact on the ability of 

U.S.-based enterprises to compete with 

foreign-based enterprises in domestic or 

export markets. Because this 

amendment is not a major regulation, no 

regulatory impact analysis is being 

conducted. This regulation was 

submitted to the Office of Management 

and Budget (OMB) for review under E.O. 

12291. 

This action does not require any 

revision to existing SIP's or changes to 

any SIP regulations. Its purpose is to 

give EPA an appropriate test method to 

enforce SIP opacity regulations where 

there are no test methods in the 

applicable SIP. The proposal will help 

EPA to enforce opacity regulations using 

the techniques originally intended by 

the States in their SIP regulations. 

Regulatory Flexibility Act 

Pursuant to the Regulatory Flexibility 

Act, 5 U.S.C, section 601 et seq., 

whenever an agency is required to 

publish a general notice of rulemaking 

for any proposed or final rule, it must 

prepare and make available for public 

comment a regulatory flexibility 

analysis which describes the impact of 

the rule on small entities (i.e., small 

businesses, small organizations, and 

small governmental jurisdictions). The 

Administrator may certify, however, 

that the rule will not have a significant 

economic impact on a substantial 

number of small entities. 

This amendment will have no adverse 

economic impact on small entities. Its 

only purpose is to assure EPA has an 

appropriate test method to enforce SIP 

opacity regulations. No new SIP 

regulations are being proposed. Since 

this amendment does not significantly 

change the status quo for such entities, I 

hereby certify that this regulation will 

not have a significant economic impact 

on a substantial number of small 

entities. This regulation therefore does 

not require a regulatory flexibility 

analysis. 

Paperwork Reduction Act 

This rule does not contain any 

information collection requirements 

subject to the Office of Management and 

Budget review under the Paperwork 

Reduction Act of 1980,44 U.S.C, 3501 et 

seq. 

List of Subjects in 40 CFR Pari! 52 

Air pollution control, ozone, sulfur 

oxides, nitrogen dioxide, lead, 

particulate matter, carbon monoxide, 

hydrocarbons. 

Dated: August 22,1986. 

Lee M. Thomas, 

Administrator. 

The EPA proposes to amend Title 40, 

Chapter I, Part 52 of the Code of Federal 

Regulations as follows: 
P.6 

Federal Register /Vol. 51, No. 168 / Friday, August 29, 1986 / Proposed Rules 

52-

1. The authority citation for Part 52 

continues to read as follows: 

Authority: Section 110 of the Clean Air Act 

as amended. 42 U.S.C. 7410. 

2. Section 52.12 is amended by 

revising paragraphs (c) introductory text 

and (c)(1) to read as follows: 

§ 52.12 Sourco surveiHanca. 

(c) For purposes of Federal 

enforcement, the following test 

procedures shall be used: 

(1) Sources subject to plan provisions 

that do not specify test procedures and 

to provisions promulgated by the 

Administrator will be tested by means 

of the appropriate procedures and 

methods prescribed in Part 60 or in Part 

52. In deciding which methods to follow, 

the Administrator will use the method or 

methods which are most consistent with 

the applicable provisions of the plan. 

* ** * o » 

3. Section 52.23 is amended by 

revising paragraph (b) to read as 

follows: 

§ 52.23 Violation and enforcement. 

* * * * *» 

(b) The promulgation of test methods 

under Parts 52 and 60 is not intended as 

a limitation on the use of evidence that 

would be otherwise admissible under 

the Federal Rules of Evidence. 

« * 6 * <* 

4. A new Appendix F is added to Part 

52 as follows: 

Appendix F—Reference Methods For EPA 

Plan Enforcement 

The test methods in this Appendix are 

referred to in § 52.12 (Source Surveillance) of 

40 CFR Part 52, Subpart A (General 

Provisions). These methods, where 

applicable, are used to determine compliance 

with SIP regulations when the SIP fails to 

specify a test method or when EPA 

promulgates SIP regulations. 

Method F-1—Visual Determination of 

Opacity of Emissions From Stationary 

Sources 

The EPA has evaluated field studies and 

other information to determine the accuracy 

of the test procedure. This information 

indicates that both positive and negative 

error may occur while reading plumes under 

contrasting conditions and using the test 

procedures of Method F-1. 

To evaluate potential positive error, a 

series of field experiments were conducted 

under controlled field conditions using light 

and dark visible plumes generated using a 

smoke generator and with a transmissometer 

meeting the specifications of Method 9. 

During these evaluation tests, panels of 

qualified observers (certified by Method 9 

procedures) read the generated plumes in S 

percent opacity increments and at 15-second 

intervals. The data were reduced for timeaveraged regulations by averaging over 

varying lengths of time, and for timeexception provisions by aggregating the 

readings above a given opacity within the 

time period. Data from the earlier field trials 

conducted in developing Method 9 also were 

evaluated. Observer measurements were 

then compared to the reference values 

measured by the smoke generator 

transmissometer. These data are included in 

the docket. Tables 1-5 indicate the 

probability of various levels of maximum 

potential positive error for time-averaged test 

procedures, over averaging periods of 2 to 6 

minutes. For any averaging times over 6 

minutes, the positive error for the 6-minute 

averaging period may be used. 

Range of Positive Error For Various 

Averaging Times Ussd in Time-Averaged 

Regulations—Tables 1-5 

Table 1. Averaging 8 Observations (2 

minutes). 

95 percent of the data sets were read with a 

positive error of 12.5 percent opacity or less 

90 percent of the data sets were read with a 

positive error of 9.5 percent opacity or less 

65 percent of the data sets were read with a 

positive error of 7.5 percent opacity or less 

80 percent of the data sets were read with a 

positive error of 6 percent opacity or less 

70 percent of the data sets were read with a 

positive error of 3 percent opacity or less 

60 percent of the data sets were read with a 

positive error of less than 1 percent opacity 

Table 2. Averaging 12 Observations (3 

minutes). 

95 percent of the data sets were read with a 

positive error of 12 percent opacity or less 

90 percent of the data sets were read with a 

positive error of 9 percent opacity or less 

65 percent of the data sets were read with a 

positive error of 7 percent opacity or less 

60 percent of the data sets were read with a 

positive error of 5.5 percent opacity or less 

70 percent of the data sets were read with a 

positive error of 3 percent opacity or less 

60 percent of the data sets were read with a 

positive error of less than 1 percent opacity 

Table 3. Averaging 16 Observations (4 

minutes). 

95 percent of the data sets were read with a 

positive error of 12 percent opacity or less 

90 percent of the data sets were read with a 

positive error of 9 percent opacity or less 

85 percent of the data sets were read with a 

positive error of 7 percent opacity or less 

80 percent of the data sets were read with a 

positive error of 5.5 percent opacity or less 

70 percent of the data sets were read with a 

positive error of 3 percent opacity or less 

60 percent of the data sets were read with a 

positive error of les than 1 percent opacity 

Table 4. Averaging 20 Observations (5 

minutes). 

95 percent of the data sets were read with a 

positive error of 11.5 percent opacity or less 

90 percent of the data sets were read with a 

positive error of 9 percent opacity or less 

85 percent of the data sets were read with a 

positive error of 8.5 percent opacity or less 

80 percent of the data sets were read with a 

positive error of 5 percent opacity or less 

70 percent of the data sets were read with a 

positive error of 2.5 percent opacity or less 

60 percent of the data sets were read with a 

positive error of less than 1 percent opacity 

Table 5. Averaging 25 Observations (8 

minutes). 

95 percent of the data sets were read with a 

positive error of 10 percent opacity or less 

90 percent of the data sets were read with a 

positive error of 7,5 percent opacity or less 

85 percent of the data sets were read with a 

positive error of 5.5 percent opacity or less 

80 percent of the data sets were read with a 

positive error of 4 percent opacity or less 

70 percent of the data sets were read with a 

positive error of 2 percent opacity or less 

60 percent of the data sets were read with a 

positive error of less than 1 percent opacity 

Table 8 indicates a range of observer errors 

in determining duration of visible emissions 

for time-exception test procedures and was 

derived by comparing observed opacity with 

actual opacity. The table expresses accuracy 

in terms of opacity error and time error 

because it was determined to be the most 

practical way of explaining accuracy for this 

method. Opacity error refers to the error 

allowance or "buffer" allowed to obtain a 

given level of accuracy. Time error refers to 

the number of 15-second observations that 

must be discounted to obtain a given level of 

accuracy. 

Table 6. Range of Observer Errors for 

Time-Exception Observations. 

92 percent of the data sets showed no 

positive error when 5 percent opacity was 

subtracted from each observation and one 

observation above the opacity limit was 

discarded for each set of 24 observations. 

87 percent of the data sets showed no 

positive error when 5 percent opacity was 

subtracted from each observation. 

81 percent of the data sets showed no 

positive error when one observaUon above 

the opacity limit was discarded for each set 

of 24 observations. 

70 percent of the data sets showed no 

positive error. 

1. Principle and Applicability 

1.1 Principle 

The opacity of emissions from sources of 

visible emissions is determined visually by a 

qualified observer. 

1.2 Applicability 

This method is applicable for the 

determination of the opacity of emissions 

from sources of visible emissions for (1) timeexception regulations, (2) time-averaged 

regulations, and (3) instantaneous limitations. 
P.7 

Federal Register / Vol. 51, No. 168 / Friday, August 29, 1988 / Proposed Rules 

1.3 Definitions 

"Time-exception regulation" means any 

regulation which allows predefined periods 

of opacity above the otherwise applicable 

opacity limit. 

"Time-averaged regulation" means any 

regulation which utilizes averaging to 

determine the opacity of visible emissions 

over a specific time period. 

"Instantaneous limitation regulation" 

means an opacity limit which is never to be 

exceeded. 

2. Procedures 

The observer qualified in accordance with 

section 3 of this method shall use the 

following procedures for visually determining 

the capacity of emissions. 

2.1 Position 

The qualified observer shall stand at a 

distance sufficient to provide a clear view of -

the emissions with the sun oriented in the 

140-degree sector to his back. Consistent with 

maintaining the above requirement, the 

observer shall, as much as possible, make his 

observations from a position such that his 

line of vision is approximately perpendicular 

to the plume direction and, when observing 

opacity of emissions from rectangular outlets 

(e.g. roof monitors, open baghouses, 

noncircular stacks), approximately 

perpendicular to the longer axis of the outlet. 

The observer's line of sight should not 

include more than one plume at a time when 

multiple stacks are involved and, in any case, 

the observer should make his observations 

with his line of sight perpendicular to the 

longer axis of such a set of multiple stacks 

(e.g., stub stacks on baghouses). 

2.2 Field Records 

The observer shall record the name of the 

plant, emission location, type of facility, 

observer's name and affiliation, and the date 

on a field data sheet. The time, estimated 

distance to the emission location, 

approximate wind direction, estimated wind 

speed, description of the sky condition 

(presence and color of clouds), and plume 

background are recorded on a field data 

sheet at the time opacity readings are 

initiated and completed. 

2.3 Observations 

Opacity observations shall be made at the 

point of greatest opacity in that portion of the 

plume where condensed water vapor is not 

present. 

The observer shall not look continuously at 

the plume, but instead shall observe the 

plume momentarily at 15-second intervals. 

2.3.1 Attached Steam Plumes 

When condensed water vapor is present 

within the plume as it emerges from the 

emission outlet, opacity observations shall be 

made beyond the point in the plume at which 

condensed water vapor is not longer visible. 

The observer shall record the approximate 

distance from the emission outlet to the point 

in the plume at which the observations are 

made. 

2.3.2 Detached Steam Plume 

When water vapor in the Plume condenses 

and becomes visible at a distinct distance 

from the emission outlet, the opacity of 

emissions should be evaluated at the 

emission outlet prior to the condensation of 

water vapor and the formation of the steam 

plume. 

2.4 Recording Observations 

Opacity observations shall be recorded to 

the nearest 5 percent at 15-second intervals 

on an observational record sheet. Each 

momentary observation recorded shall be 

deemed to represent the average of emissions 

for a 15-second period. 

2.5 Data Reduction 

2.5.1 Time-Exception Regulations 

For a time-exception regulation, reduce 

opacity observations as follows: count the 

number of observations above the applicable 

standard, and multiply that number by 0.25 to 

determine the minutes of emissions above the 

standard. 

25.2. Time-Averaged Regulations 

For a time-averaged regulation that 

provides for averaging over a period of 2 or 

more minutes, opacity observations shall be 

reduced to an average of eight, or more (as 

appropriate), consecutive observations 

recorded at 15-second intervals depending on 

the averaging time specified by the regulation 

in the State implementation plan. Divide the 

observations recorded on the record sheet 

into sets of eight, or more (as appropriate), for 

the specified averaging time. A set is 

composed of any eight or more consecutive 

observations. Sets need not be consecutive in 

time and in no case shall two sets overlap. 

For each set of observations, calculate the 

appropriate average by summing the opacity 

of the observations and dividing this sum by 

the number of observations in the set. 

2.5.3. Instantaneous Limitation Regulation 

For aninstantaneous limitation, a 2-minute 

averaging time will be used. Opacity 

observations shall be reduced by averaging 

eight consecutive observations recorded at 

15-second intervals. Divide the observations 

recorded on the record sheet into sets of eight 

consecutive observations. A set is composed 

of any eight consecutive observations. Sets 

need not be consecutive in time. In no case 

shall two sets overlap. For each set of eight 

observations, calculate the average by 

summing the opacity of the eight 

observations and dividing this sum by eight. 

3. Qualifications and Testing 

3.1 Certification Requirements 

To receive certification as a qualified 

observer, a candidate must be tested and 

demonstrate the ability to assign opacity 

readings in 5 percent increments to 25 

different black plumes and 25 different white 

plumes, with an error not to exceed 15 

percent opacity on any one reading and an 

average error not to exceed 7.5 percent 

opacity in each category. Candidates shall be 

tested according to the procedures described 

in paragraph 3.2. Smoke generators used 

pursuant to paragraph 3.2 shall be equipped 

with a smoke meter which meets the 

requirements of paragraph 3.3. 

The certification shall be valid for a period 

of 6 months, at which time the qualification 

procedure must be repeated by any observer 

in order to retain certification. 

3.2 Certification Procedure 

The certification test consists of showing 

the candidate a complete run of 50 plumes— 

25 black plumes and 25 white plumes— 

generated by a smoke generator. Plumes 

within each set of 25 black and 25 white runs 

shall be presented in random order. The 

candidate assigns an opacity value to each 

plume and records his observation on a 

suitable form. At the completion of each run 

of 50 readings, the score of the candidate is 

determined. If a candidate fails to qualify, the 

complete run of 50 readings must be repeated 

in any retest. The smoke test may be 

administered as part of a smoke school or 

training program, and may be preceded by 

training or familiarization runs of the smoke 

generator during which candidates are shown 

black and white plumes of known opacity. 

3.3. Smoke Generator Specifications 

Any smoke generator used for the purpose 

of paragraph 3.2 shall be equipped with a 

smoke meter installed to measure opacity 

across the diameter of the smoke generator 

stack. The smoke meter output shall display 

in-stack opacity based upon a path length 

equal to the stack exit diameter on a full 0 to 

100 percent chart recorder scale. The smoke 

meter optical design and performance shall 

meet the specifications shown in Table 7. The 

smoke meter shall be calibrated as 

prescribed in paragraph 3.3.1 prior to the 

conduct of each smoke reading tests. At the 

completion of each test, the zero and span 

drift shall be checked and if the drift exceeds 

±1 percent opacity, the condition shall be 

corrected prior to conducting any subsequent 

test runs. The smoke meter shall be 

demonstrated at the time of installation to 

meet the specifications listed in Table 7. This 

demonstration shall be repeated following 

any subsequent repair,or replacement of the 

photocell or associated electronic circuitry 

including the chart recorder or output meter, 

or every 8 months, whichever occurs first. 

TABLE 7.—SMOKE METER DESIGN AND 

PERFORMANCE SPECIFICATIONS 

S 

Parameter 

a Light source..- -

b. Spectral response of photocell 

c. Angle of vtevs 

d. Angle of projection -

e. Calibration error ... 

i. Zero ami span drift 

g. Response Ume -

Specification 

Incandescent lamp 

operated at 

nominal rated 

voltago. 

Photopic (daylight 

opsctral response 

of ths human oyoreferenco 4.1). 

15 degrees maximum 

total angle. 

15 degress maximum 

total angle. 

± 3 percent opacity, 

maximum. 

± 1 percent opacity, 

30 minutes. 

< 5 seconds. 

3.3.1 Calibration 

The smoke meter is calibrated after 

allowing a minimum of 30 minutes warm-up 

by alternately producing simulated opacity of 

0 percent and 100 percent. When stable 

response at 0 percent or 100 percent is noted, 

the smoke meter is adjusted to produce an 

output of 0 percent or 100 percent as 
P.8 

Federal Register / Vol. 51, No. 168 / Friday, August 29, 1986 / Proposed Rule3 31081 

appropriate. This calibration shall be 

repeated until stable 0 percent and 100 

percent readings are produced without 

adjustment. Simulated 0 percent and 100 

percent opacity values may be produced by 

alternately switching the power to the light 

source on and off while the smoke generator 

is not producing smoke. 

3.3.2 Smoke Meter Evaluation 

The smoke meter design and performance 

are to be evaluated as follows: 

3.3.2.1 Light Source. Verify from 

manufacturer's data and from voltage 

measurements made at the lamp, as installed, 

that the lamp is operated within ±5 percent 

of the nominal rated voltage. 

3.3.2.2 Spectral Response of Photocell. 

Verify from manufacturer's data that the 

photocell has a photopic response; i.e., the 

spectral sensitivity of the cell shall closely 

approximate the standard spectral-luminosity 

curve for photopic vision which is referenced 

in (b) of Table 7. 

3.3.2.3 Angle of View. Check construction 

geometry to ensure that the total angle of 

view of the smoke plume, as seen by the 

photocell, does not exceed 15 degrees. The 

total angle of view may be calculated from: 

0=2 tan"1 d/2L, where 0 = total angle of 

projection; d = the sum of the length of the 

lamp filament + the diameter of the limiting 

aperture; and L = distance from the lamp to 

the limiting aperature. The limiting aperture 

is the point in the path between the photocell 

and the smoke plume where the angle of view 

is most restricted. In smoke generator smoke 

meters this is normally an orifice plate. 

3.3.2.4 Angle of projection. Check 

construction geometry to ensure that the total 

angle of projection of the lamp on the smoke 

plume does not exceed 15 degrees. The total 

angle of projection may be calculated from: 0 

= 2 tan- - d/2L, where 0 = total angle of 

projection; d = the sum of the length of the 

lamp filament + the diameter of the limiting 

aperature; and L = the distance from the 

lamp to the limiting aperature. 

3.3.2.5 Calibration Error. Using neutraldensity filters of known opacity, check the 

error between the actual response and the 

theoretical linear response of the smoke 

meter. This check is accomplished by first 

calibrating the smoke meter according to 

3.3.1. and then inserting a series of three 

neutral-density filters of nominal opacity of 

20, 50, and 75 percent in the smoke meter 

path length. Filters calibrated within ±2 * 

percent shall be used. Care should be takenwhen inserting the filters to prevent stray 

light from affecting the meter. Make a total of 

five nonconsecutive readings for each filter. 

The maximum error on any one reading shall 

be 3 percent opacity. 

3.3.2.6 Zero and Span Drift. Determine the 

zero and span drift by calibrating and 

operating the smoke generator in a normal 

manner over a 1 -hour period. The drift is 

measured by checking the zero and span at 

tbe end of this period. 

3.3.2.7 Response Time. Determine the 

response time by producing the series of five 

simulated 0 percent and 100 percent opacity 

values and observing the time required to 

reach stable response. Opacity values of 0 

percent and 100 percent may be simulated by 

alternately switching the power to the light 

source off and on while the smoke generator 

is not operating. 

4. References 

4.1 Federal Register, Volume 39, No. 219, 

November 12,1974. Method 9—Visual 

Determination of the Opacity of Emissions 

from Stationary Sources (Appendix A). 

4.2 Technical Assistance Document: 

Quality Assurance Guideline for Visible 

Emission Training Programs, Office of Air, 

Noise, and Radiation, EPA-600/S4-83-011. 

May 1982. 

4.3 Quality Assurance Handbook for Air 

Pollution Measurement Systems: Volume IH, 

Stationary Source Specific Methods, Section 

3.12, Method 9, Visible Determination of the 

Opacity of Emissions from Stationary 

Sources, Environmental Monitoring Systems 

Laboratory, EPA-600/4-77-027(b), February 

1984. 

(FR Doc. 86-19598 Filed 8-28-86; 8:45 am) 

BILLING CODE 6560-SO-M