NEW ITEMS Meeting of the Cook County Board of Commissioners ...

page 6
NEW ITEMS
Meeting of May 1, 2007
PROPOSED ORDINANCE AMENDMENT continued
ITEM #3 cont’d
Opacity means the property of a material whereby it is partially or wholly resistant to the transmission
of light and thus also the tendency to obscure an observer's view.
Opacity, equivalent means a percentage expression of the degree of resistance to light transmission
identical in meaning to relative opacity save that the concept is extended from situations involving only
black, white and intermediate shade of grey to include also situations where coloration may be present.
Opacity, relative means a relative percentage measurement of the degree of opacity of a material on
the basis of 100 percent relative opacity or no light transmission to zero percent relative opacity or
complete light transmission; i.e. transparency. the following equivalence between Relative Opacity and
Ringelmann number shall be employed:
TABLE INSET:
Relative Opacity
(percent)
Ringelmann
Number
0 0
20 1
40 2
60 3
80 4
100 5
Fractional Ringelmann numbers represent a linear interpolation of the respective increment of Relative
Opacity.
Open air means all spaces outside of buildings, stacks or exterior ducts.
Open burning means the combustion of any matter in such a way that the products of the combustion
are emitted to the open air without originating in or passing through equipment for which an Installation
Permit could be issued by the Department.
Organic material means any chemical compound of carbon including diluents and thinners which are
liquids at standard conditions and which are used as dissolvers, viscosity reducers or cleaning agents, but
excluding compounds such as methane, carbon monoxide, carbon dioxide acid, metallic carbonic acid,
metallic carbide, metallic carbonates, and ammonium carbonate.
Organic vapor means the gaseous phase of an organic material or a mixture of organic materials
present in the atmosphere.
Parking lot means any land area used or intended to be used for the storage of passenger automobiles
or commercial vehicles.
Particulate matter means any material, other than uncontaminated water, which is suspended in or
discharged into the atmosphere in a finely divided form as a liquid or solid, or a combination thereof.
Peak level of an impulsive sound means the maximum excursion of the sound pressure level as
detected by methods and instruments approved by the Director and described in any of the Department's
Suggested Guidelines for Noise and Vibration Control when published.
Peak level impulsive vibration means the vector sum of the instantaneous peak level of all three
components, one vertical and two horizontal of the earth borne impulses measured at or beyond the
boundaries of the emitter's property.
Period of observation means the time interval during which acoustical data are obtained. The period
of observation is determined by the characteristics of the noise being measured and should also be at least
ten times as long as the response time of the instrumentation. The greater the variance in indicated sound
level, the longer must be the observation time for a given expected accuracy of the measurement.
Person means any individual, natural person, trustee, court appointed representative, syndicate,
association, partnership, firm, club, company, corporation, business trust, institution, agency, government
corporation, municipality, district or other political subdivision, department, bureau, agency or
instrumentality of Federal, State or local government, contractor, supplier, vendor, installer, operator, user
or owner, or any officer, agency, employee, factor, or any kind of representative of any thereof, in any
capacity, acting either for himself, or for any other person, under either personal appointment or pursuant
to law, or other entity recognized by law as the subject of rights and duties. The masculine, feminine,
singular or plural is included in any circumstances.