A.    Noise. For the purpose of this chapter, the following definitions pertaining to noise are adopted:

    "Decibel" means a unit of measurement of the intensity of sound (the sound pressure level).

    "Impact noise analyzer" means an instrument used in conjunction with the sound level meter to measure intensities of short duration sounds.

    "Octave band" means one of a series of eight bands which cover the normal range of frequencies included in sound measurements. Such octave bands serve to define the sound in terms of its pitch components.

    "Octave band analyzer" means an instrument used in conjunction with a sound level meter to measure sound in each of eight octave bands.

    "Sound level meter" means an instrument standardized by the American Standards Association used for measurement of the intensity of sound and is calibrated in decibels.

    B.    Vibration. For the purpose of this chapter, the following definitions pertaining to vibration are adopted:

    "Frequency" means the number of oscillations per second of a vibration.

    "Impact vibrations" means earth-borne oscillations occurring in discrete pulses at or less than one hundred (100) pulses per minute.

    "Steady state vibrations" means earth-borne oscillations that are continuous. Discrete pulses that occur more frequently than one hundred (100) times per minute shall be considered to be steady state vibrations.

    "Three-component measuring system" means a device for recording the intensity of any vibration in three mutually perpendicular directions.

    C.    Smoke, Odorous Matter and Toxic Matter. For the purpose of this chapter, the following definitions pertaining to smoke, odorous matter and toxic matter are adopted:

    "Combustion for indirect heating" means the burning of fuel in equipment, such as steam boilers, water or air heaters, stills or brew kettles, where there is no contact between the products of combustion and the materials being heated.

    "Dust" means solid particular matter capable of being air or gas-borne.

    "Particular matter" means any finely divided liquid or solid matter capable of being air or gas-borne.

    "Process weight" means the total weight of all materials used in any process which discharges dust into the atmosphere. Such materials shall include solid fuels, but not liquid or gaseous fuels or combustion air.

    "Smoke" means any visible emission into the open air from any source, except emissions of an uncontaminated water vapor.

    "Smoke unit" means a measure of the quantity of smoke being discharged and is the number obtained by multiplying the smoke density in a standard smoke chart number by the time of emission in minutes. For example, the emission of standard smoke chart Number 1 for one minute equals one smoke unit.

    "Standard smoke chart numbers" means the numbers on the standard smoke chart indicating graduations of light-obscuring capacity of smoke.

    D.    Fire, Explosives, Humidity, Heat and Glare. For the purposes of this chapter, the following definitions pertaining to fire, explosives, humidity, heat and glare are adopted:

    "Flammable or explosive materials" means materials which produce flammable or explosive vapors or gases under ordinary weather temperature including liquids with an open cup flash point of less than one hundred (100) degrees Fahrenheit.

    "Free-burning materials" means materials constituting an active fuel.

    "Intense burning materials" means materials which by virtue of low ignition temperature, high rate of burning and large heat evolution burn with intensity.

    "Moderate burning materials" means materials which in themselves burn moderately and may contain small quantities of a higher grade of combustibility.

    "Open cup flash point" means the temperature at which a liquid sample produces sufficient vapor to flash but not ignite when in contact with a flame in a Tagliabue open cup tester.

    "Original sealed containers" means containers with a capacity of not more than fifty-five (55) gallons.

    "Slow burning materials" means materials which in themselves burn moderately and may contain small quantities of a higher grade of combustibility. (Prior code § 19-1-3)