MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

1

RULE 400 VISIBLE EMISSIONS

(Adopted July 1, 1969; Revised April 26, 1995, June 18, 1997, March 22, 2000 and October 15,

2003)

CONTENTS

PART 1 GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.2 Applicability ........................................................2

1.3 Exemptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.4 Effective Dates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.5 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

PART 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.1 Abrasives Certified for Permissible Dry Outdoor Blasting ....................4

2.2 Obscurant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.3 Opacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.4 Ringelmann Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2.5 Teepee Burner . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

PART 3 REQUIREMENTS AND STANDARDS ....................................5

3.1 General Visible Emission Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.2 Industry-Specific Visible Emission Limitations .............................6

PART 4 ADMINISTRATIVE REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

4.1 Test Methods .......................................................7
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

2

PART 1 GENERAL

1.1 Purpose

The purpose of this Rule is to provide limits for the visible emissions from sources

within the District.

1.2 Applicability

The provisions of this Rule shall apply to all sources of air pollutant emissions in the

District.

1.3 Exemptions

The provisions of this Rule shall not apply to the following activities:

1.3.1 any open burning performed in compliance with Rule 407 {California Health and

Safety Code (HSC) Sections 41704 (a), (b), (c), and (e)};

1.3.2 use of any aircraft to distribute seed, fertilizer, insecticides, or other agricultural aids

over lands devoted to the growing of crops or raising of fowl or animals {HSC

Section 41704 (d)};

1.3.3 agricultural operations necessary for the growing of crops or raising of fowl or

animals {HSC Sections 41704 (g) and (h)};

1.3.4 the use of visible emission generating equipment in training sessions conducted by

governmental agencies necessary for certifying persons to evaluate visible emissions

for compliance with applicable District rules and regulations {HSC Section 41704

(l)};

1.3.5 emissions from vessels using steam boilers during emergency boiler shutdowns for

safety reasons, safety and operational tests required by governmental agencies, and

where maneuvering is required to avoid hazards {HSC Section 41704 (j)};

1.3.6 emissions from vessels during a breakdown condition, as long as the discharge is

reported in accordance with District requirements {HSC Section 41704 (k)};

1.3.7 smoke emissions from teepee burners during the disposal of forestry and agricultural

residues or forestry and agricultural residues with supplementary fossil fuels when
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

3

the emissions result from the startup or shutdown of the combustion process or from

the malfunction of emission control equipment. This exemption does not apply to

emissions which exceed a period or periods of time aggregating more than 30

minutes in any 24 hour period, nor to emissions which result from the failure to

operate and maintain in good working order any emission control equipment {HSC

Section 41704 (m)};

1.3.8 smoke emissions from burners used to produce energy and fired by forestry and

agricultural residues with supplementary fossil fuels when the emissions result from

the startup or shutdown of the combustion process or from the malfunction of

emission control equipment. This exemption does not apply to emissions which

exceed a period or periods of time aggregating more than 30 minutes in any 24 hour

period, nor to emissions which result from the failure to operate and maintain in

good working order any emission control equipment {HSC Section 41704 (n)};

1.3.9 emissions from methanol fuel manufacturing plants which manufacture not more

than 2,000,000 gallons of methanol fuel per day from wood, agricultural waste,

natural gas, or coke (exclusive of petroleum coke). As used in this Subsection,

"manufacturing plant" includes all necessary support systems, including field

operations equipment that provide feedstock. However, this exemption shall be

available to only one methanol fuel manufacturing plant in the District, and is

effective only when the District is designated as an "attainment area" pursuant to the

Federal Clean Air Act (42 U.S.C. Sec. 7401 et seq.) This exemption shall remain in

effect with respect to a plant until five years after construction of the plant and shall

have no force and effect with respect to the plant on and after that date {HSC Section

41704 (o)};

1.3.10 the use of an obscurant for the purposes of training military personnel and the

testing of military equipment by the United States Department of Defense on any

military reservation {HSC Section 41704 (p)};

1.3.11 wet plumes where the presence of uncombined water is the only reason for the

failure of an emission to meet the limitations of Section 3.1 of this Rule. The

burden of proof which establishes the application of this exemption shall be upon

the person seeking to benefit from its provisions;

1.3.12 the use of an orchard, field crop, or citrus grove heater which does not produce

unconsumed solid carbonaceous material at a rate in excess of that allowed by

State law, which is 1 gram per minute of unconsumed solid carbonaceous

material. {HSC Sections 41860 and 41704 (f)}

1.4 Effective Dates
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

4

This Rule, as most recently revised, is effective on October 15, 2003.

1.5 References

1.5.1 The requirements of this Rule arise from the provisions of: California Health &

Safety Code Sections 39043.5, 41701.5, 41701.6 ,41704 and 41860; Title 17 Section

92000 et seq. of the California Code of Regulations, and the Code of Federal

Regulations (CFR) Part 60, Part 61, and Part 63.

1.5.2 Other related rules include: Rule 407 (Open Outdoor Fires), Rule 403 (Particulate

Matter), Rule 404 (Sulfur Compounds and Nitrogen Oxides), Rule 423 (New Source

Performance Standards), and Rule 424 (National Emission Standards for Hazardous

Air Pollutants). 

PART 2 DEFINITIONS

2.1 Abrasives Certified for Permissible Dry Outdoor Blasting

The abrasive blasting material defined in Title 17 of the California Code of Regulations

Sections 92000 et seq. 

2.2 Obscurant

Fog oil released into the atmosphere during military exercises which produces a smoke

screen designed to eliminate the detection of persons or objects by visual or electronic

means of observation within a localized area. {HSC Section 39043.5}

2.3 Opacity

The degree to which light is prevented from passing through an emission plume. Its

measure is expressed as one (1.0) minus the optical transmittance of a smoke plume,

screen target, etc. as determined by the test methods in Section 4.1 below. Dark plumes

are expressed as numbers 1 through 5 on the Ringelmann chart, while light plumes are

expressed as equivalent percentages. Thus, Ringelmann 1 corresponds to 20% opacity,

Ringelmann 2 corresponds to 40% opacity, Ringelmann 3 to 60% opacity, Ringelmann
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

5

4 to 80% opacity, and Ringelmann 5 corresponds to 100% opacity. 

2.4 Ringelmann Chart

The chart used to designate shades of darkness of emissions as published by the United

States Bureau of Mines. 

2.5 Teepee Burner

A conical shaped device used to burn flammable forestry and agricultural product waste

material in an enclosed fixture effective in preventing the spread of sparks or fire,

situated in an area cleared of grass, grain, brush, slash, litter, and snags for a distance of

100 feet surrounding the device or by landfill or other methods which meet applicable

state and local fire safety, air, and water quality standards. A burn permit pursuant to

Rule 407 must be obtained for use of such device. 

PART 3 REQUIREMENTS AND STANDARDS

3.1 General Visible Emission Limitations

A person shall not discharge into the atmosphere from any emission source whatsoever

any air contaminant for a period or periods aggregating more than three minutes in any

one hour, which is as observed using the appropriate test method referenced in Section

4.1:

3.1.1 as dark or darker in shade as that designated as No. 1 on the Ringelmann

Chart, as published by the United States Bureau of Mines; or

3.1.2 of such opacity as to obscure an observer's view to a degree equal to or greater

than does smoke described in Subsection 3.1.1 above. 

3.2 Industry-Specific Visible Emission Limitations

3.2.1 Abrasive Blasting

Notwithstanding the requirements of Subsection 3.1 above, abrasive

blasting operations shall not exceed visible emissions limits set by Sections
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

6

92000 et seq. of Title 17 of the California Code of Regulations, which are

20% opacity for indoor operations using non-certified abrasive blasting

material and 40% opacity for more than 3 minutes in any hour for outdoor

operations using the following methods: wet abrasive blasting,

hydroblasting, vacuum blasting, or abrasives certified for permissible dry

outdoor blasting.

3.2.2 Drinking Water Systems

Notwithstanding the requirements of Section 3.1, emissions of visible

smoke from any diesel auxiliary engine or generator used exclusively to

operate a drinking water system shall not exceed Ringelmann 2, when

operated under emergency circumstances, or operated not more than 30

minutes each week, or two hours each month, under non-emergency

circumstances. {HSC Section 41701.6}

3.2.3 Pile Drivers

Notwithstanding the requirements of Section 3.1, pile driver operations

shall not exceed the visible emission limits set by Health and Safety Code

Sections 41701.5, which are Ringelmann 1 for no more than 4 minutes per

pile, or Ringelmann 2 for no more than 4 minutes per pile if operating on

kerosene, smoke suppressing additives and synthetic lubricating oil.

3.2.4 Federally Regulated Industries

In addition to the general visible emission limits of Section 3.1 above,

industries subject to any visible emission limit codified in 40 CFR Part 60,

40 CFR Part 61, or 40 CFR Part 63 shall comply with those limits. For

reference, District Rules 423 (New Source Performance Standards) and 424

(National Emission Standards for Hazardous Air Pollutants) include lists of

the industry-specific standards which have been promulgated in 40 CFR

Parts 60 and 61 respectively.

PART 4 ADMINISTRATIVE REQUIREMENTS

4.1 Test Methods

4.1.1 Except for any visible emission limits codified in 40 CFR Part 60, 40 CFR Part

61, or 40 CFR Part 63, all visible emissions determinations shall be in accordance
MONTEREY BAY UNIFIED AIR POLLUTION CONTROL DISTRICT

REGULATION IV

PROHIBITIONS

10/15/03 Rule 400 (Visible Emissions)

7

with EPA Method 9 (Visual Determination of the Opacity of Emissions from

Stationary Sources) except for the data reduction procedures. Data reduction

shall consist of counting the number of observations above the applicable

standard and multiplying that number by 0.25 to determine the minutes of

emissions above an applicable standard.

4.1.2 Visible emissions for any visible emission limit codified in 40 CFR Part 60, 40

CFR Part 61, or 40 CFR Part 63 shall be observed in accordance with the

observation procedure contained within EPA Method 9 or Method 22 (Visual

Determination of Fugitive Emissions from Material Sources and Smoke

Emissions from Flares), as applicable, codified as Appendix A of 40 CFR Part 60.

* * * * *