A.

The following performance standards apply to all uses permitted.

B.

Performance standards:

1.

Smoke: The requirements of the Texas Air Control Board.

2.

Particulate matter: The requirements of the Texas Air Control Board.

3.

Odor: No operation shall permit odors to be released which are detectable at an R zone boundary line and which offensively affect the sense of smell.

4.

Toxic material: The emission of toxic and noxious materials shall not produce concentrations exceeding ten percent of threshold limit values for toxic materials in industry as set forth in "Threshold Limit Values" for the current year as adopted at the annual meeting of the American Conference of Governmental Industrial Hygienists, at a zone boundary line.

5.

Glare: All artificial light sources shall be shielded so as to prevent direct rays of light from crossing a zone boundary line.

[6.

Reserved.]

7.

Vibration: Any industrial operation or activity which shall cause at any time and at any point along the nearest adjacent lot line, earthborne vibrations in excess of the limits set forth in column I (below) are prohibited. In addition, any industrial operation or activity which shall cause at any time and at any point along a zone boundary line, earthborne vibrations in excess of the limits set forth in column II are prohibited. Vibrations shall be expressed as resultant displacement in inches.

TABLE A.1

This tabulation is for steady state vibration; this is defined as continuous vibration in contrast to discrete pulses. Impact vibration, that is, discrete pulses which do not exceed 100 pulses per minute, shall not produce in excess of twice (two times) the displacement stipulated above.

8.

Noise: At no point either on the boundary of the zone or at 125 feet from the property line of the plant or operation, whichever distance is greater, shall the sound pressure level of any operation of [a] plant (other than background noises produced by sources not under control of these covenants, such as the operation of motor vehicles or other transportation facilities) exceed the decibel limits in the octave bands designated below.

TABLE A.2

Sound levels shall be measured with a sound level meter and associated octave band filter, manufactured and calibrated according to standards prescribed by the American Standards Association. Measurements shall be made using the flat or C network of the sound level meter and the fast meter movement of the octave band analyzer. Impulsive-type noises shall be subject to the performance standards hereinafter prescribed provided that such noises shall be capable of being accurately measured with such equipment. Noises capable of being so measured shall be those noises which cause rapid fluctuations of the needle of the sound level meter with a variation of no more than plus or minus two decibels. Noises incapable of being so measured, such as those of an irregular and intermittent nature, shall be controlled so as not to become a nuisance to adjacent users.

9.

Fire hazards: The storage, utilization or manufacture of solid materials or products ranging from incombustible to moderate burning is permitted. The storage, utilization or manufacture of solid materials or products ranging from free or active burning to intense burning is permitted provided the following condition is met:

Said materials or products shall be stored, utilized or manufactured within complete [completely] enclosed buildings having incombustible exterior walls and protected throughout by an automatic fire extinguishing system.

The storage, utilization or manufacture of flammable liquids or gases which produce flammable or explosive vapors shall be permitted in accordance with table A.3 (exclusive of storage of finished products in original sealed containers) and the city's fire prevention code as interpreted by the city fire marshal.

TABLE A.3

10.

Water pollution: No operation or activity shall discharge or cause to be discharged liquid or solid waste into public waters unless in conformance with the provisions of the Texas Water Quality Board.

11.

Liquid or solid waste: No discharge at any point will be allowed into any public sewer, private sewer disposal system, or stream or into the ground, except in accordance with standards approved by the state health department or standards equivalent to those approved by such department, for similar uses, of any materials of such nature or temperature as can contaminate any water supply, interfere with bacterial processes in sewage treatment or otherwise cause the emission of dangerous or offensive elements.