R307. Environmental Quality, Air Quality.

R307-201. Emission Standards: General Emission Standards.

R307-201-1. Purpose.

 R307-201 establishes emission standards for all areas of the 

state except for sources listed in section IX, Part H of the state 

implementation plan or located in a PM10 nonattainment or maintenance 

area. 

R307-201-2. Applicability.

 R307-201 applies statewide to any sources of emissions except 

for sources listed in section IX, Part H of the state implementation 

plan or located in a PM10 nonattainment or maintenance area. 

R307-201-3. Visible Emissions Standards.

 (1) Visible emissions from installations constructed on or 

before April 25, 1971, except diesel engines, shall be of a shade 

or density no darker than 40% opacity, except as otherwise provided 

in these rules. 

 (2) Visible emissions from installations constructed after April 

25, 1971, except diesel engines shall be of a shade or density no 

darker than 20% opacity, except as otherwise provided in these rules. 

 (3) Visible emissions for all incinerators, no matter when 

constructed, shall be of shade or density no darker than 20% opacity. 

 (4) No owner or operator of a gasoline powered engine or vehicle 

shall allow, cause or permit visible emissions. 

 (5) Emissions from diesel engines, except locomotives, 

manufactured after January 1, 1973, shall be of a shade or density 

no darker than 20% opacity, except for starting motion no farther 

than 100 yards or for stationary operation not exceeding three minutes 

in any hour. 

 (6) Emissions from diesel engines manufactured before January 

1, 1973, shall be of a shade or density no darker than 40% opacity, 

except for starting motion no farther than 100 yards or for stationary 

operation not exceeding three minutes in any hour. 

 (7) Visible emissions exceeding the opacity standards for short 

time periods as the result of initial warm-up, soot blowing, cleaning 

of grates, building of boiler fires, cooling, etc., caused by start-up 

or shutdown of a facility, installation or operation, or unavoidable 

combustion irregularities which do not exceed three minutes in length 

(unavoidable combustion irregularities which exceed three minutes 

in length must be handled in accordance with R307-107), shall not 

be deemed in violation provided that the executive secretary finds 

that adequate control technology has been applied. The owner or 

operator shall minimize visible and non-visible emissions during 

start-up or shutdown of a facility, installation, or operation through 

the use of adequate control technology and proper procedures. 

 (8) Compliance Method. Emissions shall be brought into 

compliance with these requirements by reduction of the total weight 

of contaminants discharged per unit of time rather than by dilution 

of emissions with clean air. 

 (9) Opacity Observation. Opacity observations of emissions 

from stationary sources shall be conducted in accordance with EPA 

Method 9. Opacity observers of mobile sources and intermittent sources 
shall use procedures similar to Method 9, but the requirement for 

observations to be made at 15 second intervals over a 6-minute period 

shall not apply. 

R307-201-4. Automobile Emission Control Devices.

 Any person owning or operating any motor vehicle or motor vehicle 

engine registered or principally operated in the State of Utah on 

which is installed or incorporated a system or device for the control 

of crankcase emissions or exhaust emissions in compliance with the 

Federal motor vehicle rules, shall maintain the system or device in 

operable condition and shall use it at all times that the motor vehicle 

or motor vehicle engine is operated. No person shall remove or make 

inoperable the system or device or any part thereof, except for the 

purpose of installing another system or device, or part thereof, which 

is equally or more effective in reducing emissions from the vehicle 

to the atmosphere. 

KEY: air pollution, PM10

Date of Enactment or Last Substantive Amendment: September 2, 2005

Notice of Continuation: March 4, 2010

Authorizing, and Implemented or Interpreted Law: 19-2-101; 19-2-104