COLORADO MINIMUM STANDARDS GOVERNING SCHOOL TRANSPORTATION 
VEHICLES 1 CCR 301 -25 
 
1.00 Statement of Basis and Purpose . 
 
The statutory authority for the Colorado Minimum Standards Governing School Transportation Vehicles 
(hereinafter referred to as “these rules” or “Minimum Standards”), adopted by the State Board of 
Education on ( insert effective date ) (hereinafter referred to as “effective date”), is found in sections 22 -
51- 108 and 42- 4-1904, C.R.S.  
 
1.1 Colorado law provides for the State Board of Education to adopt and enforce regulations 
governing the safe operation of school buses used for the transportation of students  pursuant to 
Sections 22-51-108 and 42-4-1904, C.R.S.  
 
1.2 The purpose of these rules is to adopt and enforce regulations governing the provide reasonable 
and adequate standards of safety for school transportation vehicles that promote the welfare of 
the students and afford reasonable protection to the public. The purpose of the amendments 
approved on ( insert effective date ) is to update the minim um standards to align with recent 
federal standard and reflect current industry practices ., to streamline and consolidate rules and 
eliminate rules which are redundant of and potentially contradictory to federal standards, and to 
reduce regulatory burdens for school districts and charter schools.  
 
(Note: The following two rules were moved from 5.04.)  
1.02(a)  This does not include informal or intermittent arrangements, such as sharing of actual gasoline 
expenses or participation in a carpool and the use of v ehicles rented and/or leased that are 
operated in other states.  
 
1.02(b)  Exemption: Vehicles that carry students as part of their operation as a common carrier under the 
jurisdiction of the United States Department of Transportation or Colorado  Public Utilities 
Commission are not included within the definition of a school trans portation vehicle , including 
transportation network companies . 
 
1.3 The Commissioner, or designee, may provide an exemption to these Minimum Standards to the 
extent the Commissioner finds an exemption to be appropriate.  
 
2251- R-2.00 References.  
 
FMVSS-  
 
Federal Motor Vehicle 
Safety Standards 49 C.F.R. 
Part 571, Current Revision  
National Highway Traffic Safety Administration  
 
U.S. Department of Transportation  
  
2251- R-3.00 Responsibility of  Suppliers.  
 
3.2 Dealers, distributors and manufacturers of school buses and multifunction buses each 
have a responsibility  to comply  with  the Minimum Standards  on or after the effective 
date of  these rules.  
 
3.33.2 Dealers,  distributors  or manufacturers  which  supply  school  buses  and multifunction  buses  
for use in the State of Colorado which do not meet the specifications of these rules shall 
be notified of noncompliance and a general notice will be sent to all school districts and 
school transportation operations within the State of Colorado advising that equipment 
supplied by such dealer, distributor, or manufacturer is not in compliance with the 
Minimum  Standards.  
 
3.02(a) If a dealer, distributor, or manufacturer has been notified of non -compliance in 
accordance with subsection 3.02 of these rules and replaces or modifies the equipment 
to meet the Minimum Standards, a notification of compliance will be issued from the 
Colorado Department of Education (CDE) within 30 days after proof of compliance.  
 
2251- R-42.00 Effecti ve Date . 
 
2.1 Except  as indicated  in 4.01(a),  school  transportation  vehicles  manufactured,  per the date  listed  
on the certification plate, or decal, on or after the effective date of these rules, for the purpose 
of transporting Colorado students shall meet or exceed the Minimum  Standards.  
 
4.01(a) Under federal law (49 USC 30112(a)), a new over- the-road motor coach (motor coach) 
bus may not be sold for the purpose of transporting school -age students to and from 
school or to school related events u nless it meets all FMVSS requirements for school 
buses. Upon passage of a local board of education resolution, a school district may 
purchase a used over -the-road motor coach (motor coach) bus and/or attain a short -
term rental of a motor coach bus from a c ontract carrier for the transportation of 
students to school related events. Such resolution shall specify that consideration was 
given to the standards of safety to promote the welfare of students, including 
recommendations of national transportation organizations. In no event shall a motor 
coach bus be used for the transportation of students to and from school or school to 
school. A board resolution is not necessary for transporting students on common 
carriers.  
 
4.2 School  transportation  vehicles  currently  transporting  Colorado  students  may  continue  in use. 
 
2.2 Only  sSchool  transportation  vehicles  that were  manufactured,  per the date  listed  on the 
certification plate, or decal, which are over 20 years of age are discouraged from use for 
transporting students.  within the previous 20 years, may be purchased, leased, contracted, or 
otherwise obtained for the purpose of transporting Colorado students. These vehicles must 
meet Colorado minimum standards that were in effect at the time of manufacture.  
 
2.3 School d istricts, charter schools , and service providers shall not sell or lease any school 
transportation vehicle(s) over 20 years of age, per the date listed on the certification plate, or decal, 
to any other school district, charter school , or service provider for the use of transporting Colorado 
students for any purpose.  Likewise, a school district, charter school , or service provider shall not 
purchase any school transportation vehicle over 20 years of age.  
 
2.4 School d istricts, charter  schools , and service providers shall not operate any school transportation  
vehicle that is over 25 years of age per the chassis manufacture date listed on the certification 
plate, or decal.  
 
2251- R-63.00  Testing and Certification . 
 
3.1 School bus manufacturers shall provide annual certification to the Colorado Department of 
Education  that their  product(s)  meet  or exceed  the regulations in Colorado Minimum  Standards  and 
all applicable  Federal Motor Vehicle Safety Standards ( FMVSS)  in effect at the time of manufacture. 
School bus manufacturers shall record and report to CDE the test results as required by Section 
816 - Construction. All school bus bodies that meet applicable FMVSS regulations and are in 
compliance comply with the Mi nimum Standards shall be certified by the school bus 
manufacturer by the attach ing ment a certification of a plate or  decal.  
 
3.2 It shall be the res ponsibility of the school district , 's/charter school, and service provider ’s 
responsibility  to ascertain whether all school buses purchased,  leased,  or under  contract  to the 
school  district , /charter  school , or service provider meet  all specifications  of the Minimum 
Standards. This verification should be obtained at the time of delivery, in addition to the  
statement  of compliance  in the purchase  bid, contract  for or lease  agreement.  
 
3.3 When selling a school transportation vehicle, it is the responsibility of the school district , 
's/charter school, ’s or service provider responsibility  to eliminate  the school  district , 
's/charter  school s, or service provider’s  full name  from the  vehicle.  
 
3.4 New and u Used school bus dealers shall register with the Colorado Department of 
Education, School Transportation  Unit,  certifying  that only  school  transportation  vehicles  
meeting  or exceeding Colorado Minimum Standards will be sold  to a school district, charter 
school, or service provider providing transportation from home to school, school to school 
and to school events in Colorado . There shall be no fee to  register.  
 
3.5 All school  transportation  vehicles  must  meet  and continue  to mee t all applicable  FMVSS  
regulations in effect on  the date  of manufacture,  per the date  listed  on the certification  plate  or 
decal . 
 
2251- R-34.00 Responsibility of  Suppliers . 
 
4.1 Dealers, distributors , and manufacturers of school buses and multifunction buses school 
transportation vehicles  each have a responsibility  to comply  with  the Minimum Standards  on or 
after the effective  date of  these  rules.  
 
4.2 Dealers,  distributors  or manufacturers  which  supply  school  buses  and multifunction  buses  
school transportation vehicles for use in the State of Colorado which do not meet the 
specifications of these rules shall be notified of noncompliance and a written general notice will 
be sent to all school districts , charter schools, a nd service providers  and school transportation 
operations  within the State of Colorado advising that equipment supplied by such dealer, 
distributor, or manufacturer is not in compliance with the Minimum  Standards.  
 
43.02(a) If a dealer, distributor, or manufacturer has been notified of non -compliance in 
accordance with subsection Rule 4.23.02 of these rules and replaces or modifies the 
equipment to meet the Minimum Standards, a written notification of compliance will 
be issued from the Colorado Department of Education (CDE) within 30 days after proof 
of compliance.   
 
2251- R-75.00 Bus Delivery  Requirements . 
 
57.01 The bus manufacturer shall  provide  the following  materials  and information  for direct  delivery  
to the customer upon  request:  
 
57.01(a) Line set tickets for each individual unit including chassis and body,  
 
57.01(b) A copy of the pre -delivery service performed and verified by a checkout form for each 
individual unit,  
 
57.01(c) Warranty book and statement of warranty for each individual unit,  
 
57.01(d) Service manual (hard copy or electronic copy) for each individual unit or identical units 
for all major components of the bus (e.g., body, chassis, transmission, etc.), and  
 
57.01(e) Parts manual (hard copy or electronic copy) for each individual unit or identical units 
for all major components of the bus (e.g., body, chassis, transmission, etc.).  
 
6.0 Prohibited Use  
 
6.1 4.01(a)  Under federal law (49 USC 30112(a)), a new over- the-road motor coach (motor coach) bus 
may shall not be sold for the purpose of transporting school -age students to and from school or 
to school related events unless it meets all FMVSS requirements regulations for school buses.  
 
6.01(a)  Upon passage of a local board of education resolution, a school district may purchase a 
used over -the-road motor coach (motor coach) bus and/or attain a short -term rental of 
a motor coach bus from a con tract carrier for the transportation of students to school 
related events. Such a resolution shall specify that consideration was given to the 
standards of safety to promote the welfare of students, including recommendations 
from of national transportation  organizations. In no event shall a motor coach bus be 
used for the transportation of students to and from school or school to school. A board 
resolution is not necessary for transporting students on common carriers.  
 
6.2 A motor coach bus may be used for transportation exclusively for school -related events upon 
passage of a local school board resolution and shall not  be used for transporting students to and 
from school or school to school.  
 
6.02(a) A board resolution is no t necessary for transporting students on common carriers.  
 
6.3 Per the effective date of these rules, vans that transport 14 passengers plus the driver are 
prohibited to be used to transport students.  
 
6.4 Pursuant to Section 8 of these rules , as of the effective date of these rules, all vehicles used for the 
transportation of students, for any purpose, with a capacity of more than nine passengers that do 
not meet the Colorado Rack and Load, Kentucky Pole test and FMVSS School Bus Safety Standards, 
are prohibited from being purchased (new or used) or leased for transporting students.  
 
 School  transportation  vehicles  currently  transporting  Colorado  students  may  continue  in use. 
 
2251- R-57.0 0 Definitions . 
  
5.01  School District means a public school district organized pursuant to article 30 of title 22 of 
Colorado  Revised  Statutes  or a board  of cooperative  services  (BOCES)  organized  pursuant  to 
article 5 of title 22 of Colorado Revised  Statutes.  
 
7.1 Boards of Cooperative Educational Services  - (BOCES) means a regional educational service 
unit designed to provide supporting, instructional, administrative, facility, community, or any 
other services contracted by participating. Section 22 -5-103(2)  
 
7.2        Charter School  - A charter school is a public school that operates pursuant to a charter 
contract entered into pursuant to the provisions of article 30.5 of title 22. As used in this title, 
unless the context otherwise requires, "charter school" includes any type of cha rter school 
created pursuant to the provisions of article 30.5 of title 22.  Section 22 -1-101(2)  
 
7.3  Colorado Rack and Load Tes t - verifies structural integrity and crashworthiness of school bus 
design as outlined in Rule 8.8 and Rule 8.9. The test simulates a rollover crash by applying a 
constant load along the full length of the bus body. This ensures that all pushout windows 
and emergency exits will be fully functional after an accident occurs.  
 
7.4 Kentucky Pole Test  - is designed to verify that the interior panels above the window will not 
separate and expose sharp edges in the event of a crash. The test involves a r ollover 
simulation, in which the bus strikes a pole -like object, which forces the roof to bend into the 
passenger compartment. Standards require that separation of body panels must not occur 
when the roof bends between 8 -10 inches.  
 
7.5 Fifteen Passenger Van – per federal definition USC Title 49, S ection 30117  is a fifteen -
passenger vehicle that seats 10 to 14 passengers, not including the driver.  
 
7.6 Local  Board  of Education - means  the board  of education  of a school  district  or the 
governing board of a BOCES.  
 
7.7 Motor Coach  – is a bus that has a high elevated floor, with a full row of luggage bays found 
below the main cabin.  It also has premium features such as restrooms, reclining seats, 
power outlets, television, etc.   
 
7.8 Multifunction School Activity Bus (MFSAB)  - per 49 CFR 571  is a type of school bus that is 
required to meet all FMVSS regulations applicable to school buses, except those requiring the 
installation of traffic control devices.  An MFSAB is a school bus whose purposes do not 
include transporting students to or from  home or school bus stops.  
 
7.9 Public  School District  - means a public school district that derives its support, in whole or in part, 
from moneys raised by a general state, county, or district tax  pursuant to Section 22 -1-101, C.R.S.  
 
7.10  Regenerative Braking System  - is a mechanism found on most hybrid and full -electric vehicles. It 
captures the kinetic energy from braking and converts it into the electrical power that charges the 
vehicle's high -voltage battery. Regenerative braking also slows the vehicle down, whic h assists the 
use of traditional/service brakes.  
 
7.11        SAE – Acronym for Society of Automotive Engineers, Inc . 
 
7.12  School Bus  - (FMCSA) means a passenger motor vehicle which is designed and used to carry 
more than 10 passengers in addition to the d river, and which the Secretary of Transportation 
determines is likely to be significantly used for the purpose of transporting preprimary, primary,  
or secondary school students to or from school or an event related to school. School buses are 
specifically designed for maximum safety.  
 
7.13  School Bus Eight -Way Alternating Flashing Warning Signal Lamps  - are amber and red lamps 
mounted at the same horizontal level intended to identify the vehicle as a school bus and to 
inform other users of the highway that such vehicle is stopped or about to stop on the 
roadway to take on or discharge school children.  
 
5.1 Charter school means a public school organized pursuant to Section 22 -30.5- 103(2) of 
the Colorado Revised  Statutes.  
 
7.14 School Transportation Vehicle  - means every motor vehicle which is owned by a school district 
or charter school , or service provider and operated , rented or leased  for the transportation  of 
students  to and from  school,  from school  to school, or to school related events or which is 
privately owned and operated for compensation provided that such transportation service is 
sponsored and approved by the local board of education or school’s governing board  and 
operating within the State of Colorado . 
 
7.15 Secondary Braking System  includes retarders, engine brakes, turbo brakes, driveline brakes, etc.  
 
7.16  Small Capacity Vehicle  - means a motor vehicle, which does not meet the requirements of Type A, 
B, C, or D school buses, designed for general purpose use. These vehicles ( nine  passengers including 
the driver or less) may be used to carry students to and from school, from school to school, or to 
school -related events, and shall meet or exceed all applicable rules and regulations.  
 
7.17       Specially Equipped Buses  - are buses e quipped to accommodate students with disabilities that 
is dependent upon the needs of the passengers.  
 
7.18  Transportation Network Company (TNC)  – transportation provided by a company or individual as 
part of their operation as a common carrier, or transpo rtation network company operating 
pursuant to Section 40 -10.1 -602, C.R.S., under the jurisdiction of the US Department of 
Transportation or the Public Utilities Commission.  
 
5.04(a) This does not include informal or intermittent arrangements, such as sharing of actual 
gasoline expense or participation in a car pool.  
 
5.04(b) Exemption: Vehicles that carry students as part of their operation as a common carrier 
under the jurisdiction of United States Department of Transportation or Public Utilities 
Comm ission are not included within the definition of school transportation vehicle.   
 
7.14 A School Bus shall be a motor vehicle, built to FMVSS and school bus standards contained 
herein,  designed  for transporting  students  on either  to and from  school,  from  school  to school,  or 
to school related  events.  
 
7.19  5.05(a) TYPE A --Type “A” Sschool Bbus - is a conversion or body constructed utilizing a 
cutaway front -section vehicle with a left side driver’s door and a gross vehicle weight rating 
(GVWR) of 21,500 pounds or less.  
 
5.05(b) 7.20  TYPE B -- Type “B” Sschool Bbus - is a body constructed and installed upon a 
stripped chassis.  Part of the engine  is beneath  and/or  behind  the windshield  and beside  
the driver's seat. The entrance service door is behind the  front wheels.  
 
5.05(c) 7.21 TYPE C --Type “C” Sschool Bbus - is constructed utilizing a chassis with a hood and fender 
assembly. This includes the cutaway truck chassis, including cab, with or without a left side 
driver door, and with a GVWR greater than 21,500 pounds. The entrance service door is behind 
the front wheels.  
 
5.05(d) 7.22  TYPE D -- Type “D” Sschool bbus - is constructed utilizing a stripped chassis, the engine 
may be behind the windshield and beside the driver's seat; or it may be at the rear of the bus, 
behind the rear wheels. The entrance service door is ahead of the front wheels.  
 
7.23  Vehicle Seating Capacity  - is the number of passengers (excluding the driver) assigned by the 
manufacturer as indicated on the certificate plate, or decal and cannot be changed by the 
purchaser.  
 
2251- R-148.00  Construction . (Note: This section was moved from 14.0. ) 
 
8.1 All metal surfaces that will be painted shall be chemically cleaned, etched, zinc -phosphate -coated 
and zinc -chromate or epoxy primed or conditioned by equivalent process. Particular attention 
shall be given to lapped surfaces, welded connections of structu ral members, cut edges, punched 
or drilled hole areas in sheet metal, closed or box sections,  unvented  or undrained  areas  and 
surfaces  subject  to abrasion  during vehicle  operation.  
 
8.2 The floor shall be at least 14 - gauge mill applied zinc -coated steel sheet and shall be on one 
plane. There shall be a main floor cross member of at least 10- gauge steel or equivalent 
extending  the full width  of the floor plate  and permanently  attached.  There shall be a minimum  
of two intermediate floor cross members of at least 16 - gauge steel equally between the main 
floor cross members and permanently  attached.  
 
814.02(a)   Type A buses 14,500 GVWR or less may use other metal or  material with  
strength  and corrosion  resistance  at least  equivalent  to all-steel  construction  as 
certified by the bus body  manufacturer.  
 
8.3 Subfloor shall be either five 5 ply nominal 5/8 inches thick plywood, or a material of equal or 
greater strength and insulation R value and it will equal or exceed properties of exterior- type 
softwood plywood C -D grade, as specified in National Bureau of Standards (NBS) Product 
Standard  1-83. Type A buses, 14,500 GVWR or less, shall have nominal ½ inch thick plywood or 
equivalent material equal to or exceeding  the properties listed  above. 
 
8.4 Ceiling  Panels:  If the ceiling  is constructed  to contain  lap joints,  the forward  panel  shall be lapped  
by the rear panel and the exposed edges shall be beaded, hemmed, or flanged or otherwise 
treated to eliminate sharp  edges.  
 
8.5 All body  components  shall be designed  and constructed  so as to avoid  the entrapment  
of moisture and  dust.  
 
8.6 All openings  between  chassis  and passenger -carrying  compartment  made  for any reason  must 
be sealed.  
 
8.7 On Type  B, C, and D buses,  the bus body  shall meet  the test standards  of the Kentucky  Pole  test.  
 
8.8 In addition to complying with FMVSS 220 test procedures, the body manufacturers shall 
record and report the downward vertical movement of the force at 0, 25, 50, 75, and 100% of 
the maximum force (both loading and unloading). The expected force deflection curve is 
illustrated schematically in Figure 1a. Low load nonlinearities may indicate joint 
conformation; high load nonlinearities may indicate yielding structural members.  
 
814.08(a)  A second  load  cycle  shall be performed  following  the procedure  given  in the 
first paragraph. The expected force -deflection curve is illustrated schematically in 
Figure 1b. Any  hysteresis  following  the initial shakedown  will be revealed  by this 
second  cycle.  
 
 
 
Figure 1. Static Load Test Load -Deflection Curves  
 
8.9 A diagonal (racking) load test shall be performed on Type A, B, C and D school buses to assure 
adequate  shear  stiffness  and strength  of the bus body.  Details  of the test are provided  below.  
A two - cycle loading sequence shall be conducted following the procedure described in Rule 
8.09Section 14.08 . 
 
814.09(a)  Requirements:  When a force equal to 1 ½ times the GVW is applied to the edge  of the 
roof  of the vehicle's  body  structure  through  a force  application  plate  as specified  in (b), 
Test  Procedures:  
 
814.09(a)(1) The diagonal movement of the force at any point on the  application  plate  
shall not exceed 5 1/8 inches;  and 
 
814.09(a)(2) Each emergency exit of the vehicle provided in accordance  with  FMVSS  
217 shall be capable of operation as specified in that standard during the full 
application of the force and after release of the  force.  
 
 
814.09(b)  Test Procedures:  Each  vehicle  shall be capable  of meeting  the requirements  of 
(1) and (2) when  tested  in accordance  with  the procedures  set forth  below.  
 
814.09(b)(1) The vehicle  shall be supported  on a rigid  surface  along  the lower  edge  of 
the frame or along the body sills in the absence of a  frame.  
 
814.09(b)(2) The load  shall be applied  through  a force  application  plate  that is flat and 
rigid. The dimensions of the plate shall be chosen to assure that the plate edges 
never make contact with the vehicle skin during testing. A typical width is 18 
inches. A typical length is 20 inche s less than the length of the vehicle's roof 
measured along its longitudinal  centerline.  
 
814.09(b)(3) Place  the force  application  plate  in contact  with  the edge  of the vehicle  
roof. Orient the plate so that its flat, rigid surface is perpendicular to a diagonal 
line connecting the most  distant  points  on an interior  cross  section  of the 
vehicle. The rear edge of the plate shall be positioned approximately 20 inches 
from the rear edge of the vehicle roof. A temporary stand may be used to 
support the plate until a force is  applied.  
 
814.09(b)(4) Apply an evenly distributed force in a diagonally  downward  direction  
through  the force  application  plate  at any rate not more  than  0.5 inch es per 
second, until a force of 500 pounds has been  applied.  
 
814.09(b)(5) Apply additional force in a diagonally downward direction through the 
force application plate at a rate of not more than 0.5 inch es per second 
until the force specified in (a) has been applied and maintain this 
application of force.  
 
814.09(b)(6) Measure the diagonal movement of any point on the  force  application  
plate  which  occurred  during the application  of force  in accordance  with  (5) 
and open the emergency exits as specified in  (a)(2).  
 
814.09(b)(7) Release  all diagonal  force  applied  through  the force  application  plate  and 
operate the emergency exits as specified in  814.09(a)(2).  
 
814.09(c) Test Conditions:  The following  conditions  apply  to the requirements  
specified  in (3). 
 
814.09(c)(1) Temperature: The ambient temperature is any level between  32 degrees  
Fahrenheit and 90 degrees  Fahrenheit.  
 
814.09(c)(2) Windows and Doors: Vehicle windows, doors and emergency exits  are in 
the fully  -closed position and latched but not  locked.  
814.09(d)  An alternative method of testing for the racking load test shall be  as 
follows:   
 
14.09(d)(1)  The racking load shall be applied along a line connecting the  most  
distant points on a transverse cross section of the bus interior. It produces a shear 
distortion of the cross section as shown in figure 2.  
  
A representative method of loading which employs a hydraulic jack to load a 
two- frame test ass embly is illustrated in figure 2.  
 
The maximum jack load for the two -frame assembly is determined by the 
following formula:  
 
J = 2P J -  maximum jack load for two -frame test assembly P = load/frame  
where P = DVW divided by N 
DVW - dynamic vehicle weight  
N - total number of bus body 
frames and DVW = DF x GVW  
DF - dynamic factor, not less than 1.5 
GVW - gross vehicle weight  
Thus, for a DF = 1.5, a GVW = 22,000 pounds -force (lbf), and N= 11, the 
dynamic vehicle weight is DVW = 33,000 lbf, the load/frame is P =  3000 
lbf and the maximum jack load is J = 6000 lbf.  
814.09(d)(2)  When a complete bus body is rack -loaded, the total load DVW  must  
be distributed uniformly along the bus body. One method is to mount a series 
of hydraulic jacks along the length of the bus i nterior. Seats may be removed 
to facilitate jack mounting. The rack load will be considered to be uniformly 
distributed when the variation in the hydraulic jack readings is less than 10 
percent.  A maximum load  for DVW  shall be the sum  of all jack readings.  
 
 
Transverse Cross Section  Side View  
 
Figure 2. Arrangement of Hydraulic Jack for Rack -Loading of Two -Frame 
Assembly  
 
814.09(d)(2)(A) The test may be performed on a complete bus body or on a 
representative section composed of at least two complete frames 
(body posts plus roof bows) and floor. Standard seats may be installed 
in the test section in a manner identical to that of the full bus body. 
Fabrication procedures for the test assembly shall be identical to 
normal bus body production.  
 
 
814.09(d)(2)(B) A two -cycle loading sequence shall be conducted, with 
intermediate and final load and deflection readings recorded according 
to the procedure described.  
 
814.09(d)(2)(C) The maximum deflection in line with the jack (A, maximum) 
shall not exc eed 4 four inches.  
 
814.09(d)(3)  Manufacturers shall specify which testing method was used  and 
submit  appropriate  certification  information  as called  for in 3.16.02.  
 
2251- R-329.00  Overall  Size. 
 
9.1.1 Overall length  of school  buses  shall not exceed  40 feet pursuant  to Section  42-4-504 C.R.S. 
 
9.2 Overall width of the school bus shall not exceed eight feet six inches (8’6” feet) pursuant to 8 feet, 
except under the provisions of Section 42 - 4-502 (5)(a)  C.R.S. 
 
2251- R-2810.0 0 Interior . 
 
10.1  Inside body height shall be 72 inches or more, measured metal to metal at any point on 
longitudinal  center  line from  front  vertical bow  to rear vertical bow.  Type  A school  buses  of 14,500 
GVWR or less shall have 62 inches or more inside height, measured metal to metal. Neither 
measurement shall include air conditioning  units.  
 
10.2 IThe i nterior  of a school transportation vehicle bus shall be free of all projections  likely  to cause  
injury.  
 
10.3  Global Positioning System Tablets  
 
10.3(a)  Tablets shall be mounted in a location that will not interfere with the driver’s vision.  
 
10.3(b) Wiring for the tablet is to be routed to not interfere with controls, vision, or become a 
tripping hazard. Wiring shall be hidden whenever possible.  
 
10.3(c ) When the vehicle is placed in gear, the tablet may go black, but it is still permitted to give 
auditory directions. Once the vehicle is placed into “park” the screen may then become 
visible. Districts, charter schools, and service providers may opt to ha ve the screen visible 
while driving to aid substitute and new operators.  
 
2251- R-811.0 0 Aisle . 
 
11.1  Minimum aisle  clearance  between  seats  and to all emergency  doors  shall be 12 inches  at seat 
level.  
 
11.2 On forward  control  (front  engine)  Type  D buses,  the aisle  passage  area  shall not be less than  12 
inches, measured from floor level up, between engine cover and any other object. Hold down 
fastening devices used on engine cover shall be designed to prevent hooking or catching on 
shoes or  clothing.  
 
2251- R-912.0 0 Axles .  
 
12.1 9.01 Rear axle shall be  single  -speed.  
 
2251- R-1013.00 Battery . (Low Voltage)  
 
13.1  On Type B, C and D  buses , a drawer- type pull out tray shall be provided to facilitate servicing or 
removal of battery(ies) not used for the motive propulsion of the bus. The battery(ies) shall be 
enclosed by a vented compartment, provided with drain ports, a hold down carrier mounted so 
as to avoid blocking filler ports and a latching device to prevent accidental opening. Under-
coating shall  be provided  and applied  to battery  box.  The b Battery  tray is to be equipped  with  a 
safety  device  to keep the tray from sliding completely  out. 
 
13.2 On Type  A buses  equipped  with  more  than  one battery,  all batteries  should  be positioned  in one 
location.  
 
13.3 Battery labels shall be place d at all locations where batteries are installed.  
 
13.4 Batteries  should  shall be equipped  with  sufficient  battery  cable  to allow  the drawer -type  pull out 
tray to fully  extend.  
 
2251- R-1114.00  Brakes . 
 
14.1  Type  C and D buses  shall  be equipped  with  full compressed  air brake  systems.  Both  air drum 
brake and air disc brake break applications are  acceptable.  
 
14.2  Air brakes:  
 
1411.02(a)  Compressors:  On buses  using full compressed  air brakes  for service,  emergency,  
and parking  brakes,  the compressor  shall be a standard  production  model with a 
minimum 12 cubic foot per minute  displacement.  
 
1411.02(b)  Moisture  ejection  valve:  An automatic  heated,  moisture  ejection  valve  or air 
drying system  shall be properly  installed.  This is made  to automatically  eject  
moisture, sludge,  and/or  foreign  matter  and maintain  clean,  dry air lines.  
 
1411.02(c)  Control requirements: Control valve of the parking brake system  shall be 
designed and constructed to conform with the  following:  
 
1411.02(c)(1) The parking brake  control  valve  shall be visible  to the driver and shall be 
mounted  on the dash  panel  within  15 inches  to the right  of the steering  
column.  
 
2251- R-1215.00 Bumpers . 
 
15.1  Front bumper  shall:  
 
152.01(a)  Be at least 3/16 inch thick of pressed steel channel, one piece  construction  with  
minimum of  eight  inch  width  (high),  except  Type  A buses  under  14,500  GWVR.  
 
152.01(b)  Be of extended design to offer  maximum protection of fender lines  without  
permitting snagging or  hooking.   
 
152.01(c) Be attached to the frame and extend forward of grille, head lamps,  fender  or 
hood sections to provide maximum  protection.  
 
152.01(c) Be of sufficient strength to ensure that the front of the bus may be lifted  by 
means of a bumper type jack without permanent deformation of the  bumper.  
 
15.2 Rear bumper  shall:  
152.02(a)  Be of pressed steel channel or equivalent material, at least 3/16 -inch thick,  and shall  
be a minimum  of 8 eight inches  wide  (high)  on Type  A buses,  and shall be a minimum  of 
9 ½ inches wide (high) on Type B, C and D  buses.  
 
152.02(b)  Be wrapped  around  back  corners  of bus and extend  forward  at least  12 inches  from 
rear- most point of body at floor  line.  
 
152.02(c) Be fastened  to chassis  frame  side rails in such  a manner  as to develop  full strength of 
bumper section from rear or side impact. Bracing materials shall have an impact  ratio  
comparable  to that of bumper  material and shall be fastened  at the ends  and radii  of 
the bumper,  attached  to the side of the frame  only,  and not to body  at any point.  
 
152.02(d)  Extend beyond rear -most part of body surface at least one inch,  measured  at floor  
lines.  
 
152.02(e)  Not allow  any spaces, projections,  or cut-outs  that will permit  a hand  hold  or foot 
hold.  
 
152.02(f) Have the front ends enclosed by end caps or other protective metal or have the ends 
rounded or tucked in, and shall be free from sharp edges or projections likely to cause 
injury or snagging.  
 
152.02(g)  Have  a gasket,  rubber  or equivalent,  installed  to close  opening between  the top of 
the rear bumper and body  metal.  
 
152.02(h)  Be of sufficient  strength  to permit  being pushed  by another  vehicle  of similar size.  The 
bumper shall be of sufficient strength to ensure that the rear of the bus may be lifted by  
means  of a bumper  type  jack without  permanent  deformation  of the bumper.  
 
15.3  Bumper stickers and/or signage are considered advertising. Consistent with Rule 30.09(a), 
advertising must have prior written CDE approval.  
 
15.03(a)  One bumper sticker, no larger than 3.75 inches by 15 inches, may be included on the rear 
bumper of school transportation vehicles.  
 
15.03(b)  One American flag sticker, no larger than seven  inches by 11 inches, may be included on 
the rear bumper of the school transportation vehicle consistent with the limitations 
outlined in Rule 30.09(a).  
 
15.03(c)  Bumper stickers and/or signage shall not be located in the rear windows of school 
transporta tion vehicles.  
 
15.03(d)  Bumper stickers and/or signage that do not comply with the above exemptions will  
need to be remediated.  
 
8.7 Small Vehicle shall be a motor vehicle, which does not meet the requirements of a Type A, B, C or D 
school  bus, designed  for general purpose  use. A small vehicle  shall  meet or exceed  section  
20.05 of these rules. These vehicles may be used to carry students to and from school, 
from school to school, or to school related events.  
 
5.06(a) Small vehicles shall bear name of school district/service provider plainly visible on each 
side.  
 
8.88.7 Multifunction  bus shall be a motor  vehicle,  built  to federal multifunctional  school  activity  
bus standards, designed for transporting students.  
 
5.07(a) Multifunction buses shall also meet the standards contained in the Minimum Standards 
with the exception of:  
 
5.07(a)(1)  Color, as required by section 15.00 of these  rules  
5.07(a)(2)  Lettering “SCHOOL BUS”, as required by section 26.01 of these rules  
5.07(a)(3)  Lettering “STOP ON FLASHING RED” as required by section 26.06  of 
these rules  
 
5.07(a)(4)  Alternately  flashing  warning  signal lamps,  as required  by section  29.07 of 
these rules  
Stop 5.07(a)(5)  Stop signal arm, as required by section 38.00 of  these rules  
5.07(a)(6)  Retro -reflective  material color,  as required  by section  15.02  of 
these  
rules.  
2251- R-6.00 Testing and Certification.  
 
7.77.6 School bus manufacturers shall provide annual certification to the Colorado Department 
of Education  that their  product(s)  meet  or exceed  the Minimum  Standards  and all applicable  
FMVSS in effect at the time of manufacture. School bus manufacturers shall rec ord and 
report to CDE the test results as required by Section 16 -  Construction. All school bus bodies 
that meet applicable FMVSS and are in compliance with the Minimum Standards shall be 
certified by the school bus manufacturer by the attachment of a plate or  decal.  
 
7.87.6 It shall be the school district's/charter school’s responsibility to ascertain whether all 
school buses purchased,  leased,  or under  contract  to the school  district/charter  school  meet  
all specifications  of the Minimum Standards. This verification should be obtained at the time 
of delivery, in addition to the  statement  of compliance  in the purchase  bid, contract  for or 
lease  agreement.  
 
7.97.6 When selling a school transportation vehicle, it is the school district's/charter 
school’s responsibi lity to eliminate  the school  district's/charter schools  full name  
from the  vehicle.  
 
7.10 7.6 Used school bus dealers shall register with the Colorado Department of 
Education, School Transportation  Unit,  certifying  that only  school  transportation   
vehicles  meeting  or exceeding Colorado Minimum Standards will be sold. There shall 
be no fee to  register.  
 
7.11 7.6 All school  transportation  vehicles  must  meet  and continue  to meet  all applicable  
FMVSS in effect on  the date  of manufacture,  per the date  listed  on the certification  plate.  
 
2251- R-7.00 Bus Delivery  Requirements.  
 
7.01  The bus manufacturer shall  provide  the following  materials  and information  for direct  delivery  
to the customer upon  request:  
 
7.01(a) Line set tickets for each individual unit including chassis and body,  
 
7.01(b) A copy of the pre -delivery service performed and verified by a checkout form for each 
individual unit,  
 
7.01(c) Warranty book and statement of warranty for each individual unit,  
 
7.01(d) Service manual (hard copy or ele ctronic copy) for each individual unit or identical units 
for all major components of the bus (e.g., body, chassis, transmission, etc.), and  
 
7.01(e) Parts manual (hard copy or electronic copy) for each individual unit or identical units for 
all major comp onents of the bus (e.g., body, chassis, transmission, etc.).  
 
2251- R-8.00 Aisle.  
 
8.1 Minimum aisle  clearance  between  seats  and to all emergency  doors  shall be 12 inches  at seat 
level.  
 
8.28.1 On forward  control  (front  engine)  Type  D buses,  the aisle  passage  area  shall not be less than  12 
inches, measured from floor level up, between engine cover and any other object. Hold down 
fastening devices used on engine cover shall be designed to prevent hooking or catching on 
shoes or  clothing.  
 
2251- R-9.00 Axles.  
 
9.01  Rear axle shall be  single -speed.  
2251- R-10.00  Battery.  
 
15.2 On Type B, C and D, a drawer -type pull out tray shall be provided to facilitate servicing or 
removal of battery(ies) not used for the motive propulsion of the bus. The battery(ies) shall be 
enclosed by a vented compartment, provided with drain ports, a hol d down carrier mounted so as 
to avoid blocking filler ports and a latching device to prevent accidental opening. Under- coating 
shall be provided  and applied  to battery  box.  Battery  tray is to be equipped  with  a safety  device  to 
keep tray from sliding completely  out. 
 
15.3 15.2 On Type  A buses  equipped  with  more  than  one battery,  all batteries  should  be 
positioned  in one location.  
 
15.4 15.2 Batteries  should  be equipped  with  sufficient  battery  cable  to allow  the drawer- type  pull 
out tray to fully  extend.   
 
2251- R-11.00  Brakes.  
 
11.1 Type  C and D buses  shall  be equipped  with  full compressed  air brake  systems.  Both  air drum 
brake and air disc break applications are  acceptable.  
 
11.211.1 Air brakes:  
 
11.02(a)  Compressors:  On buses  using full compressed  air brakes  for service,  
emergency,  and parking  brakes,  the compressor  shall be a standard  production  
model with a minimum 12 cubic foot per minute  displacement.  
 
11.02(b)  Moisture  ejection  valve:  An automatic  heated,  moisture  ejection  valve  or air 
drying system  shall be properly  installed.  This is made  to automatically  eject  
moisture, sludge,  and/or  foreign  matter  and maintain  clean,  dry air lines.  
 
11.02(c)  Control requirements: Control valve of the parking brake system  shall 
be designed and constructed to conform with the following:  
 
11.02(c)(1)  The parking  brake  control  valve  shall be visible  to the driver  and shall 
be mounted  on the dash  panel  within  15 inches  to the right  of the steering  
column.  
 
2251- R-12.00  Bumpers.  
 
12.1 Front bumper  shall:  
 
12.01(a)  Be at least 3/16 inch thick of pressed steel channel, one piece  construction  
with  minimum of  eight  inch width  (high),  except Type  A buses  under  14,500  GWVR.  
 
12.01(b)  Be of extended design to offer  maximum protection of fender lines  
without  permitting snagging or  hooking.  
 
12.01(c)  Be attached to the frame and extend forward of grille, head lamps,  fender  
or hood sections to provide maximum  protection.  
 
12.01(c)  Be of sufficient strength to ensure that the front of the bus may be lifted  
by means of a bumper type jack without permanent deformation of the  bumper.  
 
12.212.1 Rear bumper  shall:   
 
12.02(a)  Be of pressed steel channel or equivalent material, at least 3/16 -inch thick,  and 
shall be a minimum  of 8 inches  wide  (high)  on Type  A buses, and shall be a minimum  of 
9 ½ inches wide (high) on Type B, C and D  buses.  
 
12.02(b)  Be wrapped  around  back  corners  of bus and extend  forward  at least  12 inches  
from rear- most point of body at floor line.  
 
12.02(c)  Be fastened  to chassis  frame  side rails in such  a manner  as to develop  full 
strength of bumper section from rear or side impact. Bracing materials shall have an 
impact  ratio  comparable  to that of bumper  material and shall be fastened  at the ends  
and radii of the bumper,  attached  to the side of the frame  only,  and not to body  at any 
point.  
 
12.02(d)  Extend beyond rear -most part of body surface at least one inch,  measured  
at floor  lines.  
 
12.02(e)  Not allow  any spaces, projections,  or cut-outs  that will permit  a hand  hold  or 
foot  hold.  
 
12.02(f) Have the front ends enclosed by end caps or other protective metal or have the ends 
rounded or tucked in, and shall be free from sharp edges or projections likely to cause 
injury or snagging.  
 
12.02(g)  Have  a gasket,  rubber  or equivalent,  installed  to close  opening between  the 
top of the rear bumper and body  metal.  
 
12.02(h)  Be of sufficient  strength  to permit  being pushed  by another  vehicle  of similar  
size.  The bumper shall be of sufficient strength to ensure that the rear of the bus may 
be lifted by  means  of a bumper  type jack without  permanent  deformation  of the 
bumper.  
 
2251- R-136.00 Color . 
 
16.1  All exterior  metal  shall  be painted  National  School  Bus Glossy Yellow  (NSBY)  except for: with  
the exception  of:  
136.01(a)  Lettering  and numbering shall be black,  white,  or yellow  for bumper  area.  
163.01(b)  Bumpers and frame shall be  black . 
16.01(b)(1) Exception:  Bumpers may be colored blue or green to reflect the type of fuel 
being used in the vehicle.  
 
163.01(c) Rub rails shall may be black or yellow  at purchaser  option . 
 
16.01(c)(1) Exception:  Rub rails may be colored blue or green on an electric vehicle (EV) or 
to reflect the type of fuel being used in the vehicle.  
  
163.01(d)  Background  area for alternating  flashing  warning lamps  shall be black . 
 163.01(e)  The roof  of the bus may  be painted white,  not to extend  below  the drip rails on 
the sides of the body.  
 
163.01(f)  Student window frames, posts and service door frame may be black.  
 
16.01(g)  The hood of a bus may be painted matte black.  
 
Retro -Reflective  material shall be installed  on the bus conforming to the requirements  of FMVSS 131.  
 
13.02(a)  Rear of bus body:  strips  of between  1 and 2 inch  Retro -Reflective  NSBY  material  shall be 
applied horizontally above the rear windows and above the rear bumper, extending from the rear 
emergency exit perimeter marking outward to the left and right rear corners of the bus, with vertical strips 
applied at the corners connecting the horizontal  strips.  
13.02(b)  “School Bus” signs: Shall be marked with Retro -Reflective  NSBY  material  
comprising  background  for lettering  of the front  and/or  rear “school  bus”  signs.  
 
13.02(c) Sides  of bus body:  Shall be marked  with  Retro -Reflective  NSBY  material at least  
1 ¾ inches  in width,  extending the length  of the bus body  and located  (vertically)  as 
close as practicable to the floor line.  
 
2251- R-14.00  Construction.  
 
15.5 All metal surfaces that will be painted shall be (in addition to above requirements) chemically 
cleaned, etched, zinc -phosphate -coated and zinc -chromate or epoxy primed or conditioned by 
equivalent process. Particular attention shall be given to lapped surfaces, welded connections of 
structural members, cut edges, punched or drilled hole areas in sheet metal, closed or box sections,  
unvented  or undrained  areas  and surfaces  subject  to abrasion  during vehicle  operation.  
 
15.6 The floor shall be at least 14 gauge mill applied zinc -coated steel sheet and shall be on one 
plane. There shall be a main floor cross member of at least 10 gauge steel or equivalent extending  
the full width  of the floor plate  and permanently  attached.  There shall be a minimum  of two 
intermediate floor cross members of at least 16 gauge steel equally between the main floor cross 
members and permanently  attached.  
 
14.02(a)  Type A buses 14,500 GVWR or less may use other metal or  material with  
strength  and corrosion  resistance  at least  equivalent  to all-steel  construction  as 
certified by the bus body  manufacturer.  
 
15.7 Subfloor shall be either 5 ply nominal 5/8 inches thick plywood, or a material of equal or 
greater strength and insulation R value and it will equal or exceed properties of exterior- type 
softwood plywood C -D grade, as specified in National Bureau of Standards (NBS) Product Standard 
1-83. Type A buses, 14,500 GVWR or less, shall have nominal ½ inch thick plywood or equivalent 
material equal to or exceeding properties listed  above.  
 
15.8 Ceiling  Panels:  If the ceiling  is constructed  to contain  lap joints,  the forward  panel  shall be 
lapped by the rear panel and the exposed edges shall be beaded, hemmed, or flanged or otherwise 
treated to eliminate sharp  edges.  
  
15.9 All body  components  shall be designed  and constructed  so as to avoid  the entrapment  
of moisture and  dust.  
 
15.10  All openings  between  chassis  and passenger -carrying  compartment  made  for any reason  must 
be sealed.  
 
15.11  On Type  B, C, and D buses,  the bus body  shall meet  the test standards  of the Kentucky  Pole  test.  
 
15.12  In addition to complying with FMVSS 220 test procedures, the body manufacturers shall 
record and report the downward vertical movement of the force at 0, 25, 50, 75, and 100% of the 
maximum force (both loading and unloading). The expected force deflection curve is illustrated 
schematically in Figure 1a. Low load nonlinearities may indicate joint conformation; high load 
nonlinearities may indicate yielding structural members.  
 
14.08(a)  A second  load  cycle  shall be performed  following  the procedure  given  in the 
first paragraph. The expected force -deflection curve is illustrated schematically in 
Figure 1b. Any  hysteresis  following  the initial shakedown  will be revealed  by this 
second  cycle.  11  
  
 
 
Figure 1. Static Load Test Load -Deflection Curves  
 
15.13  A diagonal (racking) load test shall be performed on Type A, B, C and D school buses to assure 
adequate  shear  stiffness  and strength  of the bus body.  Details  of the test are provided  below.  
 
A two cycle loading sequence shall be conducted following the procedure described in Section 
14.08.  
 
14.09(a)  Requirements:  When a force equal to 1 ½ times the GVW is applied to the edge  
of the roof  of the vehicle's  body  structure  through  a force  application  plate  as specified  
in (b), Test  Procedures:  
 
14.09(a)(1)  The diagonal movement of the force at any point on the  application  
plate  shall not exceed 5 1/8 inches;  and 
 
14.09(a)(2)  Each emergency exit of the vehicle provided in accordance  with  FMVSS  
217 shall be capable of operation as specified in that standard during the full 
application of the force and after release of the  force.  
 
14.09(b)  Test  Procedures:  Each  vehicle  shall be capable  of meeting  the requirements  of 
15.13.1  and (2) when  tested  in accordance  with  the procedures  set forth  below.  
 
14.09(b)(1)  The vehicle  shall be supported  on a rigid  surface  along  the lower  edge  of 
the frame or along the body sills in the absence of a  frame.  
 
14.09(b)(2)  The load  shall be applied  through  a force  application  plate  that is flat 
and rigid. The dimensions of the plate shall be chosen to assure that the plate 
edges never make contact with the vehicle skin during testing. A typical width is 
18 inches. A typical length is 20 inches less than the length of the vehicle's roof 
measured along its longitudinal  centerline.  
 
14.09(b)(3)  Place  the force  application  plate  in contact  with  the edge  of the vehicle  
roof. Orient the plate so that its flat, rigid surface is perpendicular to a diagonal 
line connecting the most  distant  points  on an interior  cross  section  of the 
vehicle. The rear edge of the plate shall be positioned approximately 20 inches 
from the rear edge of the vehicle roof. A temporary stand may be used to  
support the plate until a force is  applied.  
 
14.09(b)(4)  Apply an evenly distributed force in a diagonally  downward  direction  
12  
 through  the force  application  plate  at any rate not more  than  0.5 inch  per 
second, until a force of 500 pounds has been  applied.  
 
14.09(b)(5) Apply additional force in a diagonally downward direction through the 
force application plate at a rate of not more than 0.5 inch per second until 
the force specified in (a) has been applied and maintain this application of 
force.  
 
14.09(b)(6)  Measure the diagonal movement of any point on the  force  
application  plate  which  occurred  during the application  of force  in 
accordance  with  (5) and open the emergency exits as specified in  (a)(2).  
 
14.09(b)(7)  Release  all diagonal force  applied  through  the force  application  plate  
and operate the emergency exits as specified in  14.09(a)(2).  
 
14.09(c)  Test  Conditions:  The following  conditions  apply  to the requirements  specified  
in (3). 
 
14.09(c)(1)  Temperature: The ambient temperature is any level between  32 
degrees  Fahrenheit and 90 degrees  Fahrenheit.  
 
14.09(c)(2)  Windows and Doors: Vehicle windows, doors and emergency exits  are in 
the fully -closed position and latched but not  locked.  
14.09(d)  An alternative method of testing for the racking load test shall be  as 
follows:  14.09(d)(1)  The racking load shall be applied along a line connecting the  
most  
distant points on a transverse cross section of the bus interior. It produces a 
shear distortion of the cross section as shown in figure 2.  
 
A representative method of loading which employs a hydraulic jack to load a 
two- frame test assembly is illustrated in figure 2.  
 
The maximum jack load for the two -frame assembly is determined by the 
following formula:  
 
J = 2 P J - maximum jack load for two -frame test assembly 
P = load/frame  
where P = DVW divided by N 
DVW - dynamic vehicle weight  
N - total number of bus body 
frames and DVW = DF x GVW  
DF - dynamic factor, not less than 1.5 13  
 GVW - gross vehicle weight  
Thus, for a DF = 1.5, a GVW = 22,000 pounds -force (lbf), and N= 11, the 
dynamic vehicle weight is DVW = 33,000 lbf, the load/frame is P = 3000 
lbf and the maximum jack load is J = 6000 lbf.  
 
14.09(d)(2)  When a complete bus body is rack -loaded, the total lo ad DVW  must  
be distributed uniformly along the bus body. One method is to mount a series 
of hydraulic jacks along the length of the bus interior. Seats may be removed 
to facilitate jack mounting. The rack load will be considered to be uniformly 
distributed when the variation in the hydraulic jack readings is less than 10 
percent.  A maximum load  for DVW  shall be the sum  of all jack readings.  
 
 
Transverse Cross Section  Side View  
 
Figure 2. Arrangement of Hydraulic Jack for Rack- Loading of Two -Frame 
Assembly  
 
14.09(d)(2)(A) The test may be performed on a complete bus body or on a 
representative section composed of at least two complete frames 
(body posts plus roof bows) and floor. Standard seats may be installed 
in the test s ection in a manner identical to that of the full bus body. 
Fabrication procedures for the test assembly shall be identical to 
normal bus body production.  
 
14.09(d)(2)(B) A two -cycle loading sequence shall be conducted, with 
intermediate and final load and deflection readings recorded according 
to the procedure described.  
 
14.09(d)(2)(C) The maximum deflection in line with the jack (A, maximum) shall 
not exceed 4 inches.  
 
14.09(d)(3)  Manufacturers shall specify which testing method was used  and 
submit  approp riate  certification  information  as called  for in 6.02.  
 
2251- R-157.00  Cooling  System . 
 
17.1  Permanent  ethylene- glycol  base  or environmentally  safe equivalent  anti-freeze  shall be provided 
to protect the cooling system to - 30 degrees Fahrenheit when tested at normal engine 
temperature.  
 
14  
 17.2  Cooling  system  shall  be equipped  with  a visual  fluid  level  indicator.  
 
2251- R-168.00  Defrosters . 
 
18.1  A defroster  system  shall be installed  of sufficient  capacity  to keep  windshield  area,  left front  
side window  to rear of driver's  vision,  and service  door  glass  area free of condensation  or ice. 
 
18.2  The defrosting  system  shall  conform to  the requirements  of the Society  of Automotive  Engineers, Inc. (SAE)  
J1945J381- 202006.  
 
18.3  A minimum of one and no more than three a djustable  six- 6 inch auxiliary fans may shall be 
installed to complement the defroster system used by the manufacturer.  Such  fans  shall be 
controlled  individually  by two-speed  switches  located  on control  panel.  Fan blades  shall be 
covered  with  a protective cage.  
 
186.03(a)  The fans shall be located so as to to not interfere with the driver’s horizontal 
line of sight  vision.  
 
2251- R-179.00 Doors . 
 
19.1  The s Service  door  shall be power  or manually  operated,  under  control  of the driver,  and so 
designed  to afford easy release and prevent accidental opening. When manual lever is used, no 
parts shall come together so as to shear or crush  fingers.  
 
19.2  Manual door controls shall not require more than 25  pounds of force to operate at any 
point throughout  the range  of operation  as tested  on a 10% grade  both  uphill  and downhill.  
Power  door controls  shall be located  within  easy  access  of the driver.  
 
19.3  The s Service door shall be located on the right side of the bus opposite the driver   and within 
the driver’s direct view.  
 
19.4  Power operated doors shall be equipped with a separate manual emergency release, 
readily accessible in the door area, either above th e service door, to the side of the service 
door or on the  dash,  so that the door  may  be opened  in event of an emergency.  The release  
shall be plainly labeled with instruction s for use. 
 
19.5  There shall be a head  bumper  pad installed  on the inside  at the top of the entrance  door.  The pad 
shall be approximately 3 three inches wide (high), at least 1 one inch thick, and extend across the 
entire top of the entrance service door  opening.  
 
2251- R-1820.00 Drive  Shaft . 
 
20.1  18.01  Each  drive  shaft  or section  thereof  shall be equipped  with  adequate  metal  guard(s)  to 
prevent  whipping through floor or dropping to ground, if    broken.  
 
21.0  Electric Drive High Voltage Specs (EV)  
 
21.1  An electric -powered school transportation vehicle shall meet all Federal Motor Vehicle Safety 
Standards and all SAE standards that are applicable at the time of manufacture.  
 
21.2  EV-Specific Labeling  15  
  
21.02(a) Each door, cover, or other panels that affords immediate access to any high voltage area 
shall be plainly marked with a hazard warning label which shall read WARNING— HIGH 
VOLTAGE or DANGER —HIGH VOLTAGE. This label shall be in a highly conspicuous place. All 
high -voltage access areas shall be equipped with a lock or otherwise secured to prevent 
unauthor ized access.  
 
21.02(b)  An EV identifying label shall be affixed to the right rear corner of the bus body. An 
additional label shall be applied to the right side of the bus rearward of the entrance door 
and to the left side of the bus aft of the driver's window.  
 
21.3  EV High Voltage Drive System Batteries  
 
21.03(a) EV High Voltage Batteries shall not be in or accessible from the interior of the school bus.  
 
21.03(b) Energy storage for the EV High Voltage Drive System shall be protected from crash impacts 
and shall be encased in a non -conductive, acid -resistant compartment. This compartment 
shall be well- ventilated to preclude the possibility of hydrogen gas buildup. Energy storage 
shall be in an area and in such a way as to provide ease of service.  
 
21.03(c)  EV High Voltage Batteries shall require automatic electrical isolation in the case of a 
vehicle crash.  
 
21.03(d) EV High Voltage -Powered Vehicles: Buses utilizing a high voltage propulsion system (more 
than  48 nominal volts) shall meet the requirements o f FMVSS 305 , Electric Powered 
Vehicles: Electrolyte Spillage and Electrical Shock Protection, except for the following:  
 
21.03(d)(1) The propulsion power source (batteries, fuel cells, etc.) shall be located outside 
the passenger compartment.  
 
21.03(d)(2) The propulsion power source enclosure shall be constructed to conform to the 
power source manufacturer’s requirements and recommendations.  
 
21.03(d)(3) Due to the much larger size and quantities of the propulsion power sources on 
larger vehicles, buses over 10,000 lbs. are permitted to exceed the 5.0 - liter spillage. 
Electrolyte damage from pro pulsion batteries and the requirements to statically 
rotate the vehicle on its longitudinal axis post - test.  
 
21.4  EV High Voltage Wiring Standards and Protection  
 
21.04(a)  Wire, cable, and conductor insulation in the High Voltage System shall provide ade quate 
insulation for the voltage used and for ambient temperatures ranging from - 15°F to 120°F. 
All high voltage circuits shall be bright orange in color or otherwise labeled as HIGH 
VOLTAGE. All high -voltage circuits shall provide adequate and automatic p rotection against 
electrical overloads caused by short circuits or other excessive current conditions through 
the use of fuses, circuit breakers, and ground fault interruption.  
 
21.04(b)  The EV Drive System shall have a system for protecting system compone nts from thermal 
damage due to electrical overload. This system shall include temperature sensors at critical 
points and be capable of reducing EV Drive System electrical power when necessary.  
 
21.04(c)  The EV High Voltage System shall be designed so that  when the ignition switch is off or in 16  
 accessory mode, the propulsion motor is positively disconnected. All other accessories 
powered by the main propulsion battery circuit shall remain operable when the ignition 
switch is in accessory mode.  
 
21.04(d)  All buses shall be equipped with an additional manual and automatic switch or device 
independent of the propulsion motor disconnect controls that permit the positive 
disconnection of all circuits from the Hybrid Drive System Batteries. This switch shall be  
operable from outside the vehicle. Each door or panel providing access to this switch shall 
be plainly marked to indicate that it is a main -power -disconnect switch or device.  
 
21.04(e)  The ignition switch circuit shall be linked to the Battery Management System and shall 
prevent driving the vehicle while it is connected to an external battery charging source.  
 
21.04(f)  Charging connection point shall be outside the passenger compartment.  
 
21.04(g)  The High Voltage System shall be designed to prevent the pa ssenger compartment from 
becoming energized.  
 
21.04(h)  Battery packs shall be cooled and heated as necessary to maintain proper operating 
temperatures.  
 
21.5  EV Instrumentation  
 
21.05(a)  In addition to the required gauges, the instrument display panel must also contain an 
indication showing the state of charge (power and/or range).  
 
21.05(b)  The instrument display panel shall have a warning light that indicates when an EV Drive 
System component exceeds a safe temperature. The warning light should illuminate prior to 
critical temperature to allow sufficient time to safely stop the bus.  
 
21.05(c)  The instrument display panel shall have a warning light that indicates when an EV Drive 
System has a mechanical or electrical fault.  
 
21.6  EV Range  
 
21.06(a ) All electric school buses shall have an OEM design which is capable of operating with a 
range of 100 miles or more on a full charge.  
 
21.7  Sound Generation  
 
21.07(a)  All electric school buses must comply with FMVSS 141  producing sound while in motion 
below 20 mph.  
 
21.8  Propulsion System  
 
21.08(a)  The propulsion system on all electric school buses shall be of sufficient power to propel the 
vehicle fully loaded up to 65 mph.  
 
21.08(b)  The propulsion system may be mounted utilizing a normal drivetrain or positioned in a way 
to provide direct power to the wheels. All propulsion systems must be contained below the 
floor line and cannot come into contact with the road surface.  
 17  
 21.9  Brakes  
 
21.09(a)  On electric school buses, brakes may produce regenerated power.  
 
21.09(b)  Park brake testing procedure :  
 
21.09(b)(1) Allow the brake system air pressure to build to at least 100 psi  
 
21.09(b)(2) Place the transmission of the vehicle in low gear release the parking brake and 
drive the vehicle forward to a speed of three (3) to five (5) mph.  
 
21.09(b)(3) While in motion place the vehicle in neutral and engage the parking brake and 
the vehicle should stop.  
 
21.10  Passenger Heating system  
 
21.10(a)  On electric school buses the heating system must be capable of meeting performance and 
design standards without a fuel -fired heater . See Section 29.0.  
 
21.10(b)  Heating systems that are independent of other cooling system functions may forgo the use 
of man ual shutoff valves to the passenger compartment as long as the flow of coolant can 
be stopped by means of a heating system shut down or electric heater control valve.  
 
2251- R-1922.00 Emergency  Exits . 
 
22.1  All emergency exits shall conform to FMVSS  217.  
 
22.2  The minimum  number  of emergency  exits  is shown  in the following  table.  A district  may  choose  
to have more emergency exits installed. Emergency doors may be installed in place of 
emergency windows.  
 
EMERGENCY EXITS TABLE  
 
BUS 
CAPACITY  ROOF HATCH  LEFT SIDE 
EMERGENCY 
WINDOW  RIGHT SIDE 
EMERGENCY 
WINDOW  1 – 45 1 0 0 
46 – 70 2 1 1 
71 - above  2 2 2 
 
22.3  Emergency  door:  
 
2219.03(a)  Emergency door(s) shall be equipped with a three 3-point latch mechanism.  The 
inside  door  handle  shall be designed  with  a guard  for protection  against  accidental  
release.  18  
  
2219.03(b)  Exterior door handle shall be of permanent hitch -proof design and  mounted  
with  enough clearance to permit opening without  touching the door surface.  
 
2219.03(c)  All emergency  door  openings  shall be completely  weather  stripped.  No 
obstruction  shall be higher  than  1/4 inch  across  the bottom of any emergency  
door opening.  
 
2219.03(d)  A head  bumper  pad shall be installed  over  the emergency  door  on the inside  of 
the bus body. The pad shall be approximately 3 three inches wide (high), at least 1 one 
inch thick, and  extend  across  the entire  top of the emergency  door  opening.  Padding 
shall be of the same materials as the padding used over the service  door.  
 
2251- R-203.00  Emergency  Equipment . 
 
23.1  The bus All school transportation vehicles, except for small capacity vehicles, shall be equipped  with  
at least  one pressurized,  5-five-pound,  dry-chemical  fire extinguisher, with  a total  rating  of not 
less than  2A10BC.  The operating  mechanism  shall be sealed  with  a type of seal that will not 
interfere with use of the fire  extinguisher.  
 
230.01(a)  Fire extinguisher  shall be securely  mounted  in an extinguisher  bracket  
(automotive type) and located in full view of and readily accessible to the driver  
within the cab, or in a location plainly indicated by appropriate signage . A pressure  
gauge  shall be so mounted  on the extinguisher  as to be easily  read  without 
removing the extinguisher from its mounted  position.  
 
23.01(b) Fire extinguishers shall be inspected annually for charging and certification to standards by 
a certified fire extinguisher technician.  
 
23.2  Small capacity vehicles shall be equipped with one securely mounted,  2½ pound, dry chemical fire 
extinguisher with a minimum rating of 1A10BC.  
 
23.3 First  Aid Kit: The bus All school transportation vehicles shall carry  one first aid kit which  shall  be 
securely  mounted  in full view  of the driver or with the location plainly indicated by appropriate 
signage markings . Additional kits may be installed. The kit(s) shall be mounted for easy  
removal.  
 
2320.02(a)  The kit shall be sealed.  The seal verifies  the integrity  of the contents  without  
opening the kit. The seal shall be designed to allow easy access to the kit’s  contents.  If 
zip ties are used to seal the kit, they must be breakaway zip ties.  
 
23.03(b)  Consideration should be given to replacing items in the First Aid Kit every 36 months due 
to the breakdown of materials.  
 
Contents of the 24 - unit First Aid Kit:  
 
Item  Unit(s)  
Adhesive Tape  1 
1 inch adhesive bandage  2 
2 inch bandage compress  1 
3 inch bandage compress  1 
4 inch bandage compress  1 19  
 3 inch  x 3 inch plain gauze pads  1 
Gauze roller bandage 2 inch wide  2 
Plain absorbent gauze – ½ square yard  4 
Plain absorbent gauze – 24 inch x 72 inch  3 
Triangular bandages  4 
Scissors, tweezers  1 
Space rescue blanket  1 
Non -latex disposable pair of gloves , pair.  1 
CPR mask or mouth to mouth airway  1 
Moisture and dustproof kit of sufficient capacity to store the required items.  
 
23.4  Emergency Reflectors: All buses school transportation vehicles shall carry three (3) bidirectional emergency 
triangle reflectors in compliance with  Section  42-4-230,  C.R.S.  and with  FMVSS  125,  contained  in a securely  
mounted  case  easily accessible  to the driver  or in a location  plainly  indicated  by appropriate  markings.  
23.4  Body fluid cleanup kit: Each All school transportation veh icles bus shall have one 
removable body fluid clean -up kit accessible to the  driver, within the cab, or in a 
location plainly indicated by appropriate signage . 
 
Contents of the Basic Body Fluid Clean -up Kit:  
 
Item  Unit(s)  
Antiseptic towelette  1 
Disinfectant towelette  1 
Absorbing powder (capable of ½ gallon absorption)  1 
Non -latex disposable pair of gloves , pair  1 
Disposable wiper towels  2 
Disposable scoop bag with closure mechanism and scraper  
Moisture and dustproof container of sufficient capacity to store the required items.  
 
23.6  Consideration should be given to replacing items in the Body Fluid Clean -Up Kit every 36 months 
due to the breakdown of materials.  
 
23.7  Each  bus All school transportation vehicles shall be equipped  with  one durable  webbing cutter  
having a full width  handgrip  and a protected  blade.  The cutter  shall be mounted  in a location  
accessible  to the seated  driver.  
 
23.07(a) Seat belt cutters shall be replaced after they have been used, or if there is any sign of rust 
or corrosion on the blade.  
 
20.1 Small vehicles  shall carry  the following  emergency  equipment:  
 
20.06(a)  Three (3) emergency triangle reflectors in a securely  mounted  case,  
20.06(b)  One 24 unit first aid kit as found in  20.02,  
20.06(c)  One securely mounted, 2 ½ pound, dry chemical  fire extinguisher with  
a minimum rating of 1A10BC,  
 
20.06(d)  One durable  webbing cutter  having a full width  handgrip  and a protected  blade.  
The cutter shall be mounted in a location accessible to the seated driver.  
 
20.06(e)  One basic body fluid clean -up kit as found in  20.04,  
 
23.8  Emergency  equipment  shall  be securely  mounted , . Emergency  equipment  shall be clearly  20  
 visible or in a location  plainly  indicated  by appropriate  signage markings . 
 
2251- R-214.00 Exhaust  System . 
 
24.1  Tailpipe shall not exit the right side of the bus  body.  
 
24.2  Exhaust  system shall  be insulated  in a manner  to prevent  any damage  to any fuel system 
component.  
 
24.3  There shall be a switch  to manually  start  the diesel  particulate  filter regeneration  process.  
 
24.4  The tailpipe shall be flush with but not extend more than one inch beyond the perimeter of the 
body  for side exit or the bumper  for rear exit except when  not needed  by an electric  powered  
bus. 
 
24.5  Tailpipe  shall not exit beneath  any fuel filler location  or beneath  any emergency  door  or lift door.  
 
2251- R-225.00 Floor  Coverings . 
 
25.1  The f Floor in the under - seat area, including tops of wheel housings, driver's compartment, aisle,  
and the kick toe board shall  be covered  with  fire-resistant  rubber  floor covering  or equivalent  that 
is non-skid and wear resistant.  
25.2  The f Floor covering in aisle shall be aisle -type, fire-resistant rubber or equivalent , non -skid, 
wear resistant,  and ribbed.  The m Minimum  overall thickness  shall be .1875  inch  measured  
from  tops  of ribs.  
 
25.3  The f Floor covering shall be permanently bonded to the floor and must not crack when 
subjected to sudden  changes  in temperature.  Bonding or adhesive  material shall be waterproof 
and shall be of type recommended by manufacturer of floor- covering material. All sea ms must 
be sealed with waterproof sealer.  
 
25.4  Cove  molding or new and emerging coatings shall be used  along  the side walls  and rear 
corners.  All floor seam  separations shall be properly bonded or secured.  
 
25.5  The entrance step treads, including the edge at floor level, shall be of the same quality as 
the aisle  material.  Step  treads  shall have  an integral white  or yellow  nosing  of 1 ½ inch  or 
more  or use diagonal stripes. Treads shall be permanently bonded to the metal steps and 
sealed t o prevent water from getting underneath the step  tread.  
 
25.6  A sealed and insulated plate shall be provided when required to access fuel tank sending unit. 
The plate  shall not be installed  under  flooring  material.  Type  A buses  14,500 GVWR  and under 
are exempt.  
 
2251- R-2326.00 Frame . 
 
26.1 No holes  shall be permitted  in the chassis  rails except when  drilled  at the manufacturing plant  or 
authorized by the  manufacturer.  
 
26.2 Any w Welding to the frame  side rails that is necessary  by design  to strengthen,  modify  or 
alter basic  vehicle configuration shall be authorized and documented by the  
manufacturer.  21  
  
2251- R-247.00 Fuel  System . 
 
27.1 All fuel tank  specifications  shall conform to  FMVSS  301,  FMVSS 303,  FMVSS  305,  National Fire 
Protection Association code 52, and/or National Fire Protection Association code 58, as 
applicable.  
 
27.2 Engine supply line shall not be mounted below fuel  tank.  Wiring shall be hidden whenever 
possible.  
 
27.3 The fuel fill cap opening in the body  skirt  shall be equipped  with  a hinged  cover  held  closed  by 
a spring or other conveniently operated  device except when not needed by an electric 
powered bus . Type A buses under 14,500 GVWR and small capacity vehicles are  exempt.  
 
28.0 Handrail  
 
28.1  For type A, B, C and D buses an assist handrail not less than 20 inches in length designed to provide 
maximum loading assistance, shall be provided in an unobstructed location inside the service door.  
 
28.2  At least one handrail shall be installed ins ide the service door. The handrail shall be a minimum of 
one inch in diameter and be constructed from corrosion -resistant material(s). The handrail(s) shall 
assist passengers during entry or exit and shall be designed to prevent entanglement, as evidenced 
by the passing of the NHTSA String and Nut test.  
 
28.3  The handrail may be offered in a color provided by and applied by the manufacturer.  
 
2251- R-259.00 Heating  System . 
 
29.1  All school  buses  shall be equipped  with  two or more  hot water  heaters  capable  of delivering  water 
to the system at a rate of six gallons per minute using an ambient temperature of 0 degree 
Fahrenheit to +10 degrees Fahrenheit and maintaining passenger compartment temperature of 
50 degrees Fahrenheit. One of the heaters shall  be located in the rear half of the bus on or behind 
the rear wheel axle line.  This standard  must be obtained without a secondary heating source.  
 
259.01(a)  Lift equipped  buses  may  place  the rear heater  under  the last row of seats  or wall 
mount. The front heater may be wall  mounted.  
 
29.2  Buses shall be equipped with front heater(s) and integrated defroster system of capacity to provide  
heat  for the front  part of the bus (including driver's  compartment)  and to keep  windshield area,  
service  door  glass,  driver's  left glass  area  and step  well clear of moisture,  ice and snow.  
29.3  Heater cores and fans shall be completely encased but designed to permit servicing 
heater assembly by removing all or part of the  case.  
 
29.4  Heater hose installation in the engine compartment shall include two shut -off valves shutting 
off coolant completely when  necessary.  
 
295.04(a)  One shut -off valve  mounted  between  the water  pump  outlet  and heater  hose  
connection.  
 
295.04(b)  One shut -off valve  mounted  between  the motor  block  and the return  heater  hose  
connection.  22  
  
295.04(c) Heater  hoses  shall  be adequately  supported  to guard  against  excessive  wear  due 
to vibration.  Hoses  shall not rub against  the chassis, body  or other  edges.  
 
29.5  The body manufacturer shall add the required amount of permanent ethylene glycol base or 
environmentally  safe equivalent  anti-freeze  after  heaters  have  been  connected  to protect 
cooling system of bus to - 30 degrees Fahrenheit tested at normal engine temperature.  
 
29.6  A heater  water  flow  regulating  valve  shall be installed  for convenient  operation  by the driver.  
 
2251- R-3026.00  dentification.  
 
30.1  School buses shall bear words “SCHOOL BUS” in black letters at least 8eight  inches high on 
both front and rear of body. Lettering shall be placed without impairment of its visibility. All 
lettering shall conform to Standard Alphabets for Highway Signs, Series B 2000. Lettering 
shall have a retro -reflective NSBY material backgroun d pursuant to Rule 36.1. (see 15.02B ) 
 
30.2  School buses shall bear name of school district/service provider on each side of the bus. 
The lettering must be black, standard, unshaded letters,  and at least  five inches in height. If 
there is insufficient space due to the length of the name of the school district, terms such as 
community, consolidated, and district may be  abbreviated.  
 
30.3  Small- capacity vehicles shall bear the name of the school district, charter school, or service 
provider plainly visible on each side of the vehicle.  
 
30.4 The manufacturer’s original rated capacity of the vehicle shall be printed to the left of the  service 
entrance door on the lower skirt in 2 two-inch characters. The word “capacity” may be 
abbreviated. (Example: Cap.  48) 
 
30.5 The numbering of individual  buses  for identification  purposes  is permissible.  
 
30.6 Lettering  and numerals  shall  be painted  or may  be pressure  sensitive  marking  of 
similar performance  quality.  
 
30.7 “STOP” shall be printed on the rear of the bus in letters at least 8 eight inches high. “ON 
FLASHING RED”  shall  be printed  below  “STOP,” in letters  at least  4 ½ inches  high.  An LED 
message  panel giving safety messages to alert motorists may be used instead of the above 
lettering. These letters  shall  be placed  in area(s)  visible  to the approaching motorist.  
 
30.8 The school  district  logo  may  be placed  above  the side window  drip line or along  the side of 
the bus , but shall not interfere  with  any required  lettering.  
 
30.9 Only  signs  and lettering  specifically  permitted  by state  law or regulation,  and any 
marking necessary  for safety  and identification,  shall appear  on the outside  of the bus. 
 
3026.0 98(a) Advertising, approved by the local board of education or charter  school’s  
governing board,  may  appear  only  on the side(s)  of the bus in the following  
areas:  
3026.0 98(a)(1)  The location  and securement  of the advertising  shall have  prior  
written  CDE approval.  
 23  
 3026.0 98(a)(2)  The signs shall not extend from the body so as to allow a handhold  
or present a danger to  pedestrians.  
 
3026.0 98(a)(3)  The signs  shall not interfere  with  the operation  of any door,  
window,  required lettering, lamps, reflectors or other device s. 
 
3026.0 98(a)(4)  The signs shall not be placed on side emergency  door(s).  
 
3026.0 98(a)(5)  Advertising signs shall  not interfere with retro -reflective tape on the  
side of the  bus. 
 
30.09(a)(6)  Bumper stickers and/or signage are considered advertising. Consistent 
with Rule 30.09(a)(1), advertising shall have prior written CDE approval.  
 
30.10 The exterior of the b Battery compartment shall be labeled with the word  “Battery”.  
 
30.1 1 Identification  of fuel type  shall be located  outside  and adjacent  to the fuel filler opening.  
 
2251- R-2731.00 Insulation.  
 
27.01  31.1  The b Bus body  shall  be fully  insulated  in the roof  including roof  bows  and all body  
panels.  Insulation  1one inch minimum  thickness  shall be fiber- glass  or equivalent  and fire 
resistant.  
 
2251- R-28.00  Interior.  
 
28.1 Inside body height shall be 72 inches or more, measured metal to metal at any point on 
longitudinal  center  line from  front  vertical bow  to rear vertical bow.  Type  A school  buses  of 
14,500 GVWR or less shall have 62 inches or more inside height, measured metal to metal. 
Neither measurement shall include air conditioning  units.  
 
28.228.1 Interior of bus shall be free of all projections  likely  to cause  injury.  
 
2251- R-2932.00  Lamps and Signals . 
 
32.1  All lamps, signals, reflectors  and their installation shall conform to the requirements of the 
Society of Automotive Engineers, Inc. (SAE) J1945 J2442 . No lettering, symbols or arrows, except 
manufacturer's markings, shall be on any  lens.  
 
32.2 Tail and stop (brake)  lamps:  
 
2932.02(a)  Bus shall be equipped with four combination red stop/tail  lamps.  Two  combination 
stop lamps shall have a lens diameter of at least 7seven  inches or 38.48 square inches.  
Two  combination  tail lamps  shall have  a lens diameter  of at least  4 four inches  or 12 
½ square inches.  
 
3229.02(b)  If the bus is equipped with a retarder, secondary braking system/or another 
system that supplements the service brake system , the four stop brake lamps shall 
be illuminated  when the braking system or other supplemental system retarder is 
activated.  
 24  
 32.3  Interior lamps:  Interior  lamps  shall be provided  which  adequately  illuminate  aisle.  A separate  
lamp shall be provided in step  well.  
 
32.4  Back -up lamps:  Back -up lamps  of minimum diameter  7 seven inch  or 38.48  square  inches,  or 
4 four-inch LED shall be  provided.  
 
32.5  Turn signal  lamps:  
 
2932.05(a)  The bus shall be equipped with two amber turn signals in front and  two amber  
turn signals in the rear. Rear turn signals shall be at least 7 seven inches or a total of 
38.48 square inches in  diameter.  
 
29.05(b)  Type  D buses  will still be required  to be equipped  with  two amber  turn  signals  
in front  with  a minimum diameter  of 7 inches  or 38.48 square  inches.  
 
3229.05( bc) On buses  over  30 feet,  a minimum  of one additional turn  signal shall be mounted  
on each  side below  window  and behind  the service  door  axis plane.  
 
School bus alternately flashing warning signal lamps:  
 
Definition: School bus alternately flashing warning signal lamps mounted at the same 
horizontal level intended to identify vehicle as school bus and to inform other users of 
highway that such vehicle is stopped or about to stop on roadway to take on or dis charge 
school children.  
 
32.6  All school buses shall be equipped with an alternating flashing eight -way warning signal lamp 
system.  
 
29.06(a) 32.7  The amber flashing warning signal lamps shall be energized manually  by a switch  
mounted  on the driver control  panel . The flashing  red warning  signal lamp  system shall be a 
sequential mode  type.  
 
29.06 (b)32.8 The flashing  warning  signal lamp  system  shall have  two pilot  or indicator  lights;  one shall 
show  amber  light  when  the amber  signal lamps  are flashing  and the other  shall show red light 
when the red signal lamps are  flashing.  
 
3229.0 68 (ca) The areas  around  the lens of each  alternat ingely  flashing  signal lamp  shall be black.  
 
32.06( bd) Visors shall be provided and securely mounted above the  dual -lamp  flashing  
warning  signals  to adequately  shade  and protect  the dual -lamp  assemblies  from sunlight 
above but not to obstruct the rear and side effectiveness of the warning lamps. LED warning 
signal lamps are not required to use  visors.  
 
32.7  Type  D rear engine  buses  shall have  two hazard  lamps  each  visible  to the rear when  the engine 
door is open. The lamps shall be wired to be illuminated when the main hazard lamp circuit is 
energized.  
 
32.8  A white flashing strobe light may be installed on the roof of a school bus. Amber lens may be 
used upon approval of local traffic regulatory authority. The Llight shall have a single clear lens 
emitting light 360 degrees around its vertical axis and may not extend above the roof more than 
8 eight inches. A manual switch and a pilot light must be included to indicate when light is in 25  
 operation. The l Lamp  must  not be capable  of activating  emergency  traffic  control  light  switches.  
 
2251- R-303.00 Mirrors.  
 
330.00 Exterior mirrors shall meet FMVSS  111.  
 
2251- R-314.00 Mounting, Body, and Chassis . 
 
34.1  Insulation  material shall be placed  at all attachment points  between  body  and chassis frame  on 
all buses , and shall be so attached to the chassis frame or body to prevent movement under 
severe operating  conditions.  
 
34.2  Body  front  shall  be attached  and sealed  to the chassis cowl  to prevent  entry  of moisture  and gases.   
 
2251- R-32.00  Overall Size.  
 
32.1 Overall length  of school  buses  shall not exceed  40 feet pursuant  to Section  42-4-504 C.R.S. 
 
32.232.1 Overall width  of the school bus shall not exceed 8 feet, except under the provisions of 
Section 42 - 4-502 (5)(a)  C.R.S. 
 
2251- R-33.00  Retarder (optional, see Section 42 -4-1901,  C.R.S.)  
 
33.1 Retarder  manufacturers  shall certify  that their  product  system  shall maintain  the speed  of the 
bus loaded  to maximum GVW  at 19.0 miles  per hour  on a 7 percent  grade  for 3.6 miles.  
 
33.2 School  buses  equipped  with  electro -magnetic  retarder(s)  shall have  increased  electrical 
system capacity commensurate with the needs of the retarder  system.  
 
Indicator light(s) shall indicate when retarder is in  operation.  
 
35.0 Multifunction School Activity Bus  (Note: This section was moved from Section 5.)  
 
Multifunction  bus shall be a motor  vehicle,  built  to federal multifunctional  school  activity  bus 
standards, designed for transporting students.  
 
35.071(a)  A Multifunction School Activity Bb us, pursuant to Rule 7.8, es shall also meet the 
standards contained in the se Minimum Standards . The Multifunction School Activity Bus shall 
comply with the following  with the exception of : 
 
35.017(a)(1) Color  shall not be traditionally National School Bus Glossy Yellow as 
required by Rule 16.1 of these rules. , as required by section 15.00 of these  rules  
 
35.017(a)(2)  Shall not have the identification ofLettering  “SCHOOL BUS”, as required by 
section  Rule 30.126.01  of these  rules   
 
35.017(a)(3)  Shall not have the identification of Lettering “STOP ON FLASHING RED” as 
required by section Rule 30.726.06  of these rules  
 
35.017(a)(4)  Shall not have a School Bus eight -way a Alternat ingely  flashing  warning  
signal lamps,  as required  by section  Rule 32.629.07  of these  rules  
 26  
 35.017(a)(5)  Shall not have a s Stop signal arm, as required by section Rule 41.1 38.00  of 
these rules   
 
35.017(a)(6)  Shall not be required to have the r Retro -reflective  material color,  as 
required  by section  Rule 36.315.02  of these rules . 
 
35.01(f)(1) Exception: A Multifunction School Activity Bus is required to meet the 
requirements of Rule 36.4 . 
 
36.0 Retro -Reflective Material (Note: This section was moved from Section 16.)  
 
36.1  Retro -Reflective  material shall be installed  on the bus conforming to the requirements  of FMVSS 
131 and 217 . 
 
36.2  Rear of bus body:  strips  of between  1 one- and 2 two-inch Retro -Reflective  NSBY  material  shall be 
applied horizontally above the rear windows and above the rear bumper, extending from the rear 
emergency exit perimeter marking outward to the left and right rear corners of the bus, with 
vertical strips applied at the corners connecting the horizontal  strips.  
 
36.3  “School Bus” signs: Shall be marked with Retro -Reflective  NSBY  material  comprising 
background  for lettering  of the front  and/or  rear “school  bus”  signs.  
 
36.4  “Activity Bus” signs: shall be marked with retro -reflective in white material comprising background for 
the lettering of the front and/or rear of the multifunction school activity bus.  
 
36.5  Sides of bus body:  Shall be marked  with  Retro -Reflective  NSBY  material at least  1 ¾ inches  in 
width,  extending  the length  of the bus body  and located  (vertically)  as close as practicable to the 
floor line.  
 
2251- R-347.00 Rub Rails . 
 
37.1  There shall be one rub rail located on each side of bus at approximately seat level which shall 
extend  from  rear side of entrance  service door  completely  around  the bus body  (except for 
emergency  and/or access  door)  to point  of curvature  near  outside  cowl  on left side.  
 
37.2  There shall be one rub rail located at approximately floor line which shall cover the same 
longitudinal areas  as the upper  rub rail, except at the wheel  housing,  and shall extend  at least  to 
the radii of right  and left rear corners.  
 
37.3  There shall be one rub rail located  on each  side of bus at the bottom  of the side skirts,  or a 
side skirt stiffener of equivalent  strength.  
 
37.4  Rub rails shall be attached  at each  body  post  and all other  upright  structural members.  
 
37.5  Rub rails shall be 4 four inches  or more  in width,  16-gauge  steel,  or equivalent  strength,  
constructed  in corrugated or ribbed fashion and shall be  self- draining.  
 
37.6  Rub rails shall be applied  to the outside  of the body  panels.  Pressed -in or snap -on rub rails do not 
satisfy this  requirement.  
 
2251- R-358.00 Seats/Restraining  Barriers . 
 27  
 38.1  Type  A school  buses  shall be equipped  with  restraining  barriers  conforming  to FMVSS 222.  
 
38.2  No bus shall be equipped with jump seats or portable  seats any type of seats that are not secured 
to the floor by the manufacturer . 
 
38.3  Forward -most  pupil  seat  on right  side of bus shall be located  not to interfere  with  driver's  
vision. The seat shall not be farther forward than the barrier behind driver or rear of driver's 
seat when adjusted to its rear -most  position.  
 
38.4  Use of a flip seat  at any side emergency  door  location  in conformance  with  FMVSS  222,  including 
required aisle width to side door, is acceptable. Any flip seat shall be free of sharp projections on 
the underside of the seat bottom. The underside of the flip -up seat bottoms shall be padded or 
contoured to reduce the possibility of snagged clothing or injury during use. Flip seats shall be 
constructed to prevent passenger limbs from becoming entrapped between the seat back and the 
seat cushion when in the upright position. The seat cushion shall be designed to rise to a vertical 
position automatically when not  occupied.   
38.4  School bus student seats and seat spacing shall meet FMVSS  222.  
 
38.5  School bus seat materials shall meet FMVSS  302.  
 
38.7  Integrated child seats shall not be installed at an emergency exit.  
 
38.8  Each individual wheelchair securement system shall consist of materials from one brand only.  
 
2251- R-369.00 Steering Gear  Assembly . 
 
39.1  All school  bus chassis,  in all passenger  capacities  shall be equipped  with  heavy -duty,  truck -type 
integral power  steering.  Power  steering  components  shall be compatible  with  the GVW  rating.  
 
39.2  No changes  shall be made  in the steering  apparatus  that are not authorized  in 
writing  by manufacturer.  
 
39.3  There shall be a clearance  of at least  2 two inches  between  steering  wheel  and any other  
surface  or control.  
 
2251- R-3740.00 Steps . 
 
40.1  The f First service  door  step  shall be not less than  10 ten inches  from the  ground  while the 
vehicle is in motion  (12 inch for Type D) and not more than 14 16 inches from the ground  (16 
inches for Type  D) when measured from the top surface of the step to the ground. An auxiliary 
step may be provided to compensate for the increase in ground -to-first step clearance. The 
auxiliary step is not required to be enclosed . 
 
40.2  Step  risers  shall not exceed  a height  of 10 inches.  When  plywood  is used  on the top step,  the 
riser height may be increased by the thickness of the wood.  
 
An assist  hand  rail not less than  20 inches  in length  designed  to provide  maximum  loading 
assistance,  shall  be provided  in an unobstructed  location  inside  doorway.  
40.3 The s Surface of steps shall be of non -skid material.  
 
2251- R-3841.00 Stop Signal  Arm . 28  
  
41.1  The stop signal arm shall meet FMVSS  131.  The stop signal arm may extend up to but shall not 
exceed 6.5 feet in length from the side of the bus.  
 
41.2  Rubber  spacers  shall be installed  on either  the side of the bus or the stop  arm so as to 
prevent the sign from making abrasive contact with the side of the  bus. 
 
41.3  The w Wind guard shall be provided to keep the sign in retracted  position.  
 
2251- R-3942.00  Storage  Compartment . 
 
39.01  42.1  A metal  container  of adequate  strength  and capacity  for the storage  of tire chains,  tow 
chains,  and such  tools  as may  be necessary  for minor  emergency  repairs while  bus is in route  
may  be provided. The storage container may be located either inside or outside the 
passenger compartment. If inside, the storage compartment shall be securely fastened to 
prevent the contents  from  spilling  and shall have  a latched  or secured  cover  other  than  a seat  
cushion.  
 
2251- R-403.00 Sun Visor . 
 
430.01 An interior,  adjustable,  sun visor  shall be installed  not less than  six6 inches  wide  and 30 inches  
long.  Type A school buses 14,500 GVWR or less shall have a sun visor according to 
manufacturer’s standard  size.  
 
2251- R-441.00 Tires and Rims . 
 
44.1  Minimum tire and rim sizes for vehicles with a 10,000 GVWR or greater, shall be in 
accordance with FMVSS  120.  21  
  
44.2  Dual rear tires shall be provided on Type B, C and D school  buses  shall have dual rear tires . 
 
44.3  All wheels  shall be one-piece  disc type.  Split  or multi -piece  rims  are not acceptable.  
 
2251- R-425.00 Tow  Hooks . 
 
45.1  Two  front  heavy  duty  tow hooks /loops  or two eyes  shall  be furnished  and factory  installed,  
except  on Type  A and B buses.  Hooks  shall not extend  beyond  the front  bumper  on any 
school  bus shall be factory installed on the front of Type C and D buses . 
 
45.2  Two  rear heavy -duty  tow hooks /loops  or eyes  shall be fastened  securely  to the rear of the 
frame  and shall not protrude beyond outer edge of the  bumper  shall be factory installed on 
the rear of school buses . 
 
45.3  Hooks/loops shall not extend beyond the front or rear bumper on any school bus.  
 
2251- R-436.00 Undercoating . 
 
46.1  The entire underside of the bus body, including floor sections, cross members, and below floor 
line side panels, shall be coated with rust -proofing material meeting or exceeding performance 
requirements of Society of Automotive Engineers, Inc. (SAE)  J1945 . 
 
46.2  The undercoating material shall be applied  with  suitable  airles s or conventional  spray  
equipment as per manufacturer recommended film thickness and shall show no evidence of 
voids in the cured  film.  
 
46.3  The undercoating material shall not cover  any exhaust  components  of the chassis.  
 
2251- R-447.00 Ventilation.  
 
44.01  47.1  Buses School transportation vehicles in excess  more than of  20 feet in length  shall be 
equipped  with  a multi -speed  powered  exhaust  roof ventilator or powered  vent  fan in roof  
hatch,  mounted  in the rear half of the bus. 
 
2251- R-458.00 Windshield Wipers and Washers . 
 
48.1  The wipers  shall be operated  by one or more  air or electric  motors.  If one motor  is used,  the 
wipers  shall  work  in tandem  to give full sweep  of windshield.  
 
48.2  All wiper  controls  shall be located  within  easy  reach  of the driver  and designed  to move  
blades from the driver's direct view when in stop  position.  
 
48.3  For Type  A over  14,500  GVWR,  B, C and D buses,  tThe system reservoir capacity  shall be a 
minimum of one  gallon.  
 
2251- R-469.00 Wiring . 
 
46.01  49.1  Wiring:  All wiring  shall conform to  the requirements  of the Society  of Automotive  
Engineers,  Inc. (SAE)  J1945J2202.  
 21  
 469.01(a)  An appropriate  identifying diagram  (color  plus a name  or number  code)  for all 
chassis  electrical  circuits  shall be provided  to the body  manufact urer for distribution  to 
the end  user.  
 
496.01(b)  A body  wiring  diagram,  sized  to be easily  read,  shall be furnished  with  each  bus body  
or affixed  to an area  convenient  to the electrical accessory  control  panel.  
 
496.01(c) Each wire passing through metal openings shall be protected by a  grommet.  
2251- R-47.00  Specially Equipped Buses.  
 
47.1 Equipping buses to accommodate students with disabilities is dependent upon the needs of 
the passengers. Buses equipped with equipment to accommodate the student needs are not to 
be considered a separate class of school bus, but a regular school bus equipp ed for special 
accommodations. It is recognized by the entire industry that the field of special transportation 
is characterized by varied needs for individual cases and by a rapidly emerging technology. A 
flexible,  “common -sense”  approach  to the adoption  and enforcement  of specifications  is 
prudent.  
 
47.2 Buses equipped  for transporting  students  with  special transportation  needs  shall comply  
with applicable  FMVSS.  
 
47.02(a)  Buses with power lifts shall comply with FMVSS 403, Platform Lift  Systems for 
Motor  Vehicles,  and FMVSS  404,  Platform  Lift Installation in Motor  Vehicles  
 
47.02(b)  A ramp device may  be used in lieu of a mechanical lift if the ramp meets all the 
requirements  of the Americans  with  Disabilities  Act (ADA)  as found  in 36 CFR § 1192.23, 
Vehicle  Ramp.  
 
47.02(c)  Buses with  power  lifts or ramps  shall display  the international symbol  of 
accessibility  on all four  sides  of the bus. The  symbols shall be a minimum  of 6 inches  and 
not exceed 12 inches. Such emblems shall be white on blue  background.  
 
47.02(d)  The term wheelchair tiedown and occupant restraint system (WTORS ) is used  to 
refer to the total system that secures the wheelchair and restrains the wheelchair 
occupant. A wheelchair tiedown and occupant restraint system installed in specially 
equipped buses shall be designed, installed, and operated for use with forward -facing 
wheelchair- seated passengers and shall comply with all applic able requirements of 
FMVSS 222, School Bus Passenger Seating and Crash Protection and FMVSS 302 
Flammability of Interior  Materials.