NEW JERSEY STATE DEPARTMENT OF ENVIRONMENTAL PROTECTION

NEW JERSEY ADMINISTRATIVE CODE

TITLE 7, CHAPTER 27B-2

AIR TEST METHOD 2

PROCEDURES FOR THE VISUAL DETERMINATION

OF THE OPACITY (PERCENT) AND SHADE OR APPEARANCE

(RINGELMANN NUMBER) OF EMISSIONS FROM SOURCES

Promulgated: April 21, 1976

To be effective: June 21, 1976

TABLE OF CONTENTS

7:27B-2.1 Definitions

7:27B-2.2 Acceptable Observation Methods

7:27B-2.3 Observation Principle

7:27B-2.4 General Observation Requirements

7:27B-2.5 Required Observation Data

7:27B-2.6 Certification

Reference

Appendix 1 Plume Observation Record

7:27B-2.1 Definitions

Terms not defined in this section are intended to be used as defined in the New

Jersey Air Pollution Control Act, N.J.A.C. 26:2C-1 et seq. and the Administrative Code,

Title 7, Chapter 27, or are used in their common engineering or scientific sense.

"Bureau" means the Bureau of Air Pollution Control.

"Department" means the Department of Environmental Protection.

"Opacity" means the property of a substance which renders it partially or wholly

obstructive to the transmission of visible light expressed as the percentage to which the

light is obstructed.

"Ringelmann Number" means a number used to describe the density of smoke as

determined from the Ringelmann Smoke Chart.

"Ringelmann Smoke Chart" means the "Ringelmann Scale for Grading the

Density of Smoke" as published by the United States Bureau of Mines or any chart,

recorder, indicator or device which is approved by the Department as the equivalent of

the Ringelmann Scale for the measurement of smoke density.

7:27B-2.2 Acceptable Observation Methods

Observations shall be conducted in accordance with methods set forth hereinafter.

Alternate methods and/or procedures, including the use of auxiliary equipment and

instruments, may be used subject to prior approval by the Department. The Department

may itself employ such alternates when warranted by observation conditions or other

circumstances.

7:27B-2.3 Observation Principle

For purposes of observing emissions in accordance with applicable provisions of

the rules of the Bureau, opacity (percent) and shade or appearance (Ringelmann Number)

shall be determined visually by a certified observer. Opacity (percent) is applicable to all

plumes regardless of color. Shade or appearance (Ringelmann Number) is applicable to

gray and black plumes only. The resultant observation shall be the aggregate of

individual readings.

7:27B-2.4 General Observation Requirements

(a) The observer shall stand at a distance sufficient to provide a clear view of

the emissions.

(b) The observer shall be located so that:

1. for percent opacity readings, the sun shall be oriented in the 140o

sector to the observer's back.

2. for Ringelmann Number readings, the sun should be oriented in the

140o sector to the observer's back; however, where conditions do

no permit, the sun need not be to the observer's back.

(c) Observations shall be directed to the point of greatest percent opacity or

greatest Ringelmann Number in the plume.

(d) Consistent with the requirements of subsections 2.4(a) and (b), the

observer shall make observations using a line of vision as close to 90o as

possible to the direction of the plume at the point specified in subsection

2.4(c).

(e) The observer shall not look continuously at the plume, but shall observe

the plume momentarily at 15-second intervals, except where consecutive

second standards are prescribed (e.g., N.J.A.C. 7:27-3.4 and 3.5).

(f) For plumes which contain visible water ("steam" plumes):

1. Where visible water is present within the plume at the point of

discharge to the outdoor atmosphere ("attached" plume),

observations shall be made beyond the transition point after which

water is no longer visible in the plume.

2. Where water vapor in the plume condenses and becomes visible at

a distance after the point of discharge to the outdoor atmosphere

("detached" plume), observations should be made before the

transition point where water vapor becomes visible in the plume.

7:27B-2.5 Required Observation Data

Data to be determined and reported for each observation must include the

information required to complete the Plume Observation Record (Form AIR-14,

Appendix 1) as well as information showing the sun's orientation to the observer's back

and the plume characteristics when observing a plume containing visible water as set

forth in subsection 2.4(f).

7:27B-2.6 Certification

(a) To be certified, an observer must satisfactorily complete a training course,

approved by the Department, in observing and recording opacity and

shade or appearance of visible plumes. Certification may be made by the

Department or by any person approved by the Department for such

purpose. An observer must have been certified (or recertified) within a

period of approximately six months immediately preceding the

observation.

(b) To be certified, an observer must demonstrate the ability to assign opacity

readings in five percent increments and Ringelmann number readings in ¼

scale increments. Certification tests shall consist of no less than 25 plume

observations in each plume category. Errors must not exceed 15 percent

(3/4 Ringelmann number) on any one reading in each category.

Substantially equivalent performance standards for observer certification

may be approved by the Department.

Reference

Federal Register, Volume 39, Number 219, November 12, 1974, EPA

Method 9, Visual Determination of the Opacity of Emission from Stationary Sources, is

available from the Superintendent of Documents, US Government Printing Office,

Washington, DC 20402

Appendix 1 – Opacity Observation Form

GENERAL NOTE

Editor's Note: In addition to the above text, Appendix 1 was filed with these rules, but

not reproduced herein. Further information regarding this Appendix may be obtained

by contacting:

Bureau of Technical Services

Division of Environmental Regulation

Department of Environmental Protection

CN 437 (380 Scotch Road)

Trenton, New Jersey 08625-0437