These are the KRS (Kentucky Reformed Statues) that I found pertaining to this thread. I will also include the KRS for the definitions of vehicles reconized by the state.
http://www.lrc.ky.gov/krs/189-00/910.PDF
189.910 Definitions for KRS 189.920 to 189.950.
(1) As used in KRS 189.920 to 189.950, "emergency vehicle" means any vehicle used for emergency purposes by:
(a) The Department of Kentucky State Police;
( B) A public police department;
© The Department of Corrections;
(d) A sheriff's office;
(e) A rescue squad;
(f) An emergency management agency if it is a publicly owned vehicle;
(g) An ambulance service or medical first-response provider licensed by the Kentucky Board of Emergency Medical Services, for any vehicle used to respond to emergencies or to transport a patient with a critical medical condition;
(h) Any vehicle commandeered by a police officer;
(i) Any vehicle with the emergency lights required under KRS 189.920 used by a paid or volunteer fireman or paid or volunteer ambulance personnel, or a paid or local emergency management director while responding to an emergency or to a location where an emergency vehicle is on emergency call;
(j) An elected coroner granted permission to equip a publicly or privately owned motor vehicle with lights and siren pursuant to KRS 189.920; or
(k) A deputy coroner granted permission to equip a publicly or privately owned motor vehicle with lights and siren pursuant to KRS 189.920.
(2) As used in KRS 189.920 to 189.950, "public safety vehicle" means public utility repair vehicle; wreckers; state, county, or municipal service vehicles and equipment; highway equipment which performs work that requires stopping and standing or moving at slow speeds within the traveled portions of highways; and vehicles which are escorting wide-load or slow-moving trailers or trucks.
Effective: June 8, 2011
History: Amended 2011 Ky. Acts ch. 17, sec. 1, effective June 8, 2011; and ch. 99, sec. 1, effective June 8, 2011. -- Amended 2006 Ky. Acts ch. 173, sec. 24, effective July 12, 2006. -- Amended 1998 Ky. Acts ch. 226, sec. 106, effective July 15, 1998; and ch. 426, sec. 124, effective July 15, 1998. -- Amended 1996 Ky. Acts ch. 233, sec. 9, effective July 15, 1996. -- Amended 1992 Ky. Acts ch. 211, sec. 16, effective July 14, 1992. -- Amended 1986 Ky. Acts ch. 220, sec. 1, effective July 15, 1986; and ch. 419, sec. 1, effective July 15, 1986. -- Created 1970 Ky. Acts ch. 93, sec. 1.
Legislative Research Commission Note (6/8/2011). This section was amended by 2011 Ky. Acts chs. 17 and 99, which are in conflict. Under KRS 446.250, Acts ch. 99, which was last enacted by the General Assembly, prevails.
http://www.lrc.ky.gov/krs/189-00/920.PDF
189.920 Flashing lights and sirens.
(1) All fire department, rescue squad, or publicly owned emergency management agency emergency vehicles and all ambulances shall be equipped with one (1) or more flashing, rotating, or oscillating red lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle, and a siren, whistle, or bell, capable of emitting a sound audible under normal conditions from a distance of not less than five hundred (500) feet. This equipment shall be in addition to any other equipment required by the motor vehicle laws.
(2) All state, county, or municipal police vehicles and all sheriffs' vehicles used as emergency vehicles shall be equipped with one (1) or more flashing, rotating, or oscillating blue lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle, and a siren, whistle, or bell, capable of emitting a sound audible under normal conditions from a distance of not less than five hundred (500) feet. This equipment shall be in addition to any other equipment required by the motor vehicle laws.
(3) By ordinance, the governing body of any city or county may direct that the police or sheriffs' vehicles in that jurisdiction be equipped with a combination of red and blue flashing, rotating, or oscillating lights.
(4) All public safety vehicles shall be equipped with one (1) or more flashing, rotating, or oscillating yellow lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle. Yellow flashing, rotating, or oscillating lights may also be used by vehicles operated by mail carriers while on duty, funeral escort vehicles, and church buses.
(5) All Department of Corrections vehicles used as emergency vehicles shall be equipped with one (1) or more flashing, rotating, or oscillating blue lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle. The Department of Corrections vehicles shall not be equipped with or use a siren, whistle, or bell. The equipment prescribed by this subsection shall be in addition to any other equipment required by motor vehicle laws.
(6) (a) If authorized by the legislative body of a county, urban-county, charter county, consolidated local government, or unified local government:
1. All publicly owned county jail and regional jail vehicles used as emergency vehicles may be equipped with the one (1) or more flashing, rotating, or oscillating blue lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle; and
2. An elected jailer or the chief administrator of a county or regional jail not managed by an elected jailer may equip one (1) personally owned vehicle with one (1) or more flashing, rotating, or oscillating blue lights, visible under normal atmospheric conditions from a distance of five hundred (500) feet to the front of the vehicle.
( B) Publicly owned county jail or regional jail vehicles shall not be equipped with
or use a siren, whistle, or bell.
© The equipment prescribed by this subsection shall be in addition to any other
equipment required by the motor vehicle laws.
(7) Red flashing lights may be used by school buses.
(8) No emergency vehicle, public safety vehicle, or any other vehicle covered by KRS
189.910 to 189.950 shall use any light of any other color than those specified by
KRS 189.910 to 189.950. Sirens, whistles, and bells may not be used by vehicles
other than those specified by KRS 189.910 to 189.950, except that any vehicle may
be equipped with a theft alarm signal device which is so arranged that it cannot be
used by the driver as an ordinary warning signal.
(9) Vehicles used as command posts at incidents may be equipped with and use when
on scene, a green rotating, oscillating, or flashing light. This light shall be in
addition to the lights and sirens required in this section.
(10) A personal vehicle used by a paid or volunteer firefighter, ambulance personnel, or
emergency services director who is responding to an emergency shall display the
lights required in subsection (1) of this section.
(11) An elected coroner may equip a publicly or privately owned motor vehicle, or both,
with flashing, rotating, or oscillating red and blue lights and a siren meeting the
requirements of this section solely for the purpose of responding to a report of the
death of a human being subject to the following terms and conditions:
(a) The coroner makes a written request to the legislative body of the county,
urban-county, charter county, consolidated local government, or unified local
government in which the coroner was elected to equip a publicly or privately
owned motor vehicle, or both, with flashing, rotating, or oscillating red and
blue lights and a siren meeting the requirements of this section, and that
request is approved by the legislative body by ordinance or by court order;
( B) The coroner may use the lights and siren only while responding to the scene of
the report of a death of a human being and shall not, KRS 189.940 to the
contrary notwithstanding, exceed the posted speed limit; and
© The permission granted pursuant to this section shall expire upon the coroner
leaving office or the legislative body revoking the authorization.
(12) A deputy coroner certified pursuant to KRS Chapter 72 may equip a publicly owned
or privately owned motor vehicle, or both, with flashing, rotating, or oscillating red
and blue lights and a siren meeting the requirements of this section solely for the
purpose of responding to a report of the death of a human being, subject to the
following terms and conditions:
(a) The deputy coroner has made a written request to the coroner to equip a
publicly owned or privately owned vehicle with flashing, rotating, or
oscillating red and blue lights meeting the requirements of this section and the
coroner has approved the request in writing;
( B) The coroner makes a written request to the legislative body of the county,
urban-county, charter county, consolidated local government, or unified local
government in which the coroner is elected to permit the deputy coroner to equip a publicly owned motor vehicle or privately owned motor vehicle, or both, and that request has been approved by the legislative body by ordinance or by court order;
© The deputy coroner may use the lights and siren only while responding to the scene of the report of the death of a human being and shall not, KRS 189.940 to the contrary notwithstanding, exceed the posted speed limit; and
(d) The permission granted pursuant to this section shall expire upon the coroner leaving office or the legislative body revoking the authorization.
Effective: June 8, 2011
History: Amended 2011 Ky. Acts ch. 17, sec. 2, effective June 8, 2011; and ch. 99, sec. 2, effective June 8, 2011. -- Amended 2006 Ky. Acts ch. 173, sec. 25, effective July 12, 2006. -- Amended 1998 Ky. Acts ch. 226, sec. 107, effective July 15, 1998. -- Amended 1992 Ky. Acts ch. 211, sec. 17, effective July 14, 1992. -- Amended 1986 Ky. Acts ch. 419, sec. 2, effective July 15, 1986. -- Amended 1984 Ky. Acts ch. 55, sec. 1, effective July 13, 1984. -- Created 1970 Ky. Acts ch. 93, sec. 2.
Legislative Research Commission (6/8/2011). This section was amended by 2011 Ky. Acts chs. 17 and 99, which do not appear to be in conflict and have been codified together.
189.378 Funeral processions.
(1) "Funeral procession," as used in this section, means two (2) or more vehicles accompanying the body of a deceased person when each vehicle has its headlights on or is displaying a pennant attached in such a manner as to be clearly visible to approaching traffic.
(2) A vehicle in a funeral procession has the right-of-way at an intersection and may proceed through the intersection if the procession is led by an escort vehicle displaying flashing yellow, red, or blue lights, except:
(a) When the right-of-way is required by an emergency vehicle as defined by KRS 189.910;
( B) When vehicles in the procession are directed otherwise by a police or safety officer; or
© When the vehicle is a train or locomotive.
(3) Before assuming the right-of-way, a person who drives a vehicle in a funeral procession shall exercise due caution with regard to crossing traffic.
(4) A person who drives a vehicle that is not part of a funeral procession shall not drive the vehicle between the vehicles of the funeral procession or otherwise interfere with the progress of the procession, except when:
(a) The person is authorized to do so by a police or safety officer; or
( B) The vehicle is an emergency vehicle as defined by KRS 189.910.
(5) A person who drives a vehicle that is not a part of a funeral procession shall not illuminate the vehicle headlights or engage in any other act for the purpose of securing the right-of-way granted to funeral processions.
(6) The escort vehicle, hearse, or other vehicles in a procession may be equipped with flashing amber lights for the purpose of notifying the general public of the procession and gaining the right-of-way at intersections, or signaling the end of a procession.
(7) Persons authorized to use flashing lights as defined in KRS 189.920 may use them while accompanying a funeral procession to warn traffic that a procession is approaching or that it is in progress.
(8) When a funeral procession is in progress, a person driving a vehicle not in the procession shall not pass or overtake any vehicle in the procession unless:
(a) The person is directed to do so by a police or safety officer;
( B) The procession is on a street, road, or highway outside the corporate limits of a city, town, or urban-county; or
© The procession is on an interstate highway or a state parkway.
(9) Any person who violates this section shall be guilty of a Class B misdemeanor.
I will also note from personal observation some private security services using green lights. However, according to the KRS above, green is for command vehicles and to be used in addition to the command vehicle's appropriate colored lights.
Kentucky is one of a few states that now require public school buses to have white (or clear) strobes mounted on top of the bus.