1  
  
COLORADO MINIMUM STANDARDS GOVERNING SCHOOL TRANSPORTATION 
VEHICLES 1 CCR 301 -25 
 
1.0 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 and school transportation vehicles 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 buses and 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 minimum standards to 
align with recent federal standard s 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 vehicles 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 scho ol 
transportation 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  2  
  
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 MinimumStandards.  
 
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 Effective  Date . 
 
2.1 Except  as indicated  in Rule  64.01(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  MinimumStandards.  
 
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 unless it meets all FMVSS requirements for school buses. Upon passage of a local board of education resolution, a school district may purchase a use d over -the-road motor coach (motor coach) bus and/or attain a short - 
term rental of a motor coach bus from a contract carrier for the transportation of students to school related events. Such resolution shall specify that consideration was given to the sta ndards 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 resoluti on is not necessary for transporting students on common 
carriers.  
 
4.2 School  transportation  vehicles  currently  transporting  Colorado  students  may  continue  in use. 
 
2.2 School districts, charter schools, and service providers are discouraged from operating Only 
school transportation buses, per Rule 7.12, vehicles that were manufactured, per the date listed 
on the certification plate, or decal, which are over 25 years of age. 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 ofmanufacture.  
 
2.3 School districts, charter schools, and service providers shall not sell or lease any school bus or 
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 3  
 Colorado students for any purpose. Likewise, a school district, charter school, or service provider 
shall not purchase any school bus or school transportation vehicle over 20 years of age.  
 
2.4 School districts, charter schools, and service providers are discouraged from operating school 
transportation small capacity vehicles per Rule 7.16 that were manufactured, per the date listed on 
the certification plate, or decal, which are over 15 years of  age. 
 
2251-R-6 3.00 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 Minimum Standards and shall be certified by the school bus 
manufacturer by the attach ing ment a certification of a plate  ordecal.  
 
3.2 It shall be the responsibility of the school district , 's/charter school, and ser vice 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 responsibilit y 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 related events in Colorado . There shall be no fee  toregister.  
 
3.5 All school transportation vehicles must meet and continue to meet all applicable FMVSS 
regulations  in effect  on the date  of manufacture,  per the date  listed  on the certification  plate  or 
decal . 
 
2251-R-3 4.00 Responsibility of Suppliers.  
 
4.1 Dealers, distributors , and manufacturers of school buses and multifunction buses school buses 
and 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 buses and 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, and service providers and sc hool 
transportation operations within the State of Colorado advising that equipment supplied by 
such dealer, distributor, or manufacturer is not in compliance with the  MinimumStandards.   
  
 
43.02(a) If a dealer, distributor, or manufacturer has been notified of non -compliance in 
accordance with subsection Rule 4.2 3.02 of these rules and replaces or modifies the 
equipment to meet the Minimum Stand ards, a written notification of compliance will 
be issued from the Colorado Department of Education (CDE) within 30 days after proof 
of compliance.  
 
2251-R-7 5.00 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 , charter school  
 
and/or attain a short -term rental of a motor coach bus from a contract 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 st udents, 
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 stu dents 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. A motor coach shall not be used for transporting 
students to and from school or school to school for route  purposes . 
 
6.02(a) A board resolution is not necessary for transporting students on common carriers.  
 
 
6.4 Effective January 1, 2025, pursuant to Section 8 of these rules, vehicles with a capacity of more  than  
12 passengers  that do not meet  the Colorado  Rack  and Load,  Kentucky  Pole  test and FMVSS School   
4 6.3 Type B, C, and D multifunction buses shall not be used for transporting students to and from school  
for route purposes.   or service  provider  may purchase a used over -the-road motor coach (motor coach) bus 
 5  
  
 
6.5 Per the effective date of these rules, school transportation vehicles, per Rule 7.14, owned or leased by the 
school district, charter school or service providers that are used for student transportation shall  not have the 
windows  obstructed  in any way by advertising,  decorations  or vehicle  wraps.  
6.05(a)   Exception: Tint applied by the vehicle manufacturer to industry standards.  
 
 
 
  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 RevisedStatutes.  
 
7.1 Boards of C ooperative 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 charter school 
created pursuant to the provisions of article 30.5 of title 22.  Section  22-1- 101(2)  
 
7.3 Colorado Rack and Load Test - is designed to verify the 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 functi onal 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 rollover 
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 mu st not occur 
when the roof bends between 8 -10 inches.  
 
7.5 Fifteen Passenger Van – is a van, not a Type A School bus, that has the capacity of 
transporting 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.  Bus Safety Standards, as required, are prohibited from transporting students for any  reason.  
6.05(b)  Exception: Route identification is permitted per 1CCR 301 -26, 16.04.  
6.6 Any type of passenger vehicle with a fiberglass roof shall not be permitted to transport students unless it  
meets Colorado Rack and Load.  6  
  
 
7.8 Multifunction School Activity Bus (MFSAB) - 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. Pursuant to Rule 6.3, Type B, C, and D multifunction buses shall not be used for transporting students to and from home to school for route  purposes. 
 
7.08(a) Exception: Per 1 CCR 301 -26, 18.1, Type A Multifunction buses may be used to 
transport students to and from school, school to school for route purposes and 
activities.  
 
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 Sys tem – this 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 do wn, which assists the 
use of traditional/service  brakes.  
 
7.11 SAE – Acronym for Society of Automotive Engineers,  Inc. 
 
7.12 School Bus - means a passenger motor vehicle which is designed and used to carry more than 12 
passengers in addition to the driver, 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 privat ely 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 (12 passengers includi ng 
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 equipped to accommodate studen ts with disabilities that 
are dependent upon the needs of the  passengers. 7  
  
 
7.18 Transportation Network Company (TNC) – transportation provided by a company or individual as 
part of their operation as a common carrier, or transportation 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 
Commission are not included within the definition of school transportation vehicle.  8  
  
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” Ss chool 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 thefront 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 the 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” Ss chool 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, z inc-phosphate -coated 
and zinc -chromate or epoxy primed or conditioned by an 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, close d 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 i ntermediate 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  ormaterial 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.  9  
 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  the 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 as 
outlined in Rule  7.4. 
 
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  structuralmembers.  
 
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 theapplication plate 
shall not exceed 5 1/8 inches; and  
 
814.09(a)(2) Each emergency exit of the vehicle provided in accordancewith FMVSS  
10  
 217 shall be capable of operation as specified in that standard during the full 
application of the force and after release of theforce.  
 
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 inches 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 diagonallydownward 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 bee napplied.  
 
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 s this 
application of force. 
 
814.09(b)(6) Measure the diagonal movement of any point on theforce application 
plate which occurred during the application of force in accordance with Rule 
8.09(b) (5) and open the emergency exits as specified in Rule8.09(a)(2).  
 
814.09(b)(7) Release all diagonal force applied through the force application plate and 
operate the emergency exits as specified in Rule 814.09(a)(2).  
 
814.09(c) Test Conditions: The following conditions apply to the requirements 
specified in Rule 8.09(b) (3).  
 
814.09(c)(1) Temperature: The ambient temperature is any level between32 degrees 
Fahrenheit and 90 degrees Fahrenheit.  
 
814.09(c)(2) Windows and Doors: Vehicle windows, doors and emergency exitsare in 
the fully - closed position and latched but notlocked.  
 
814.09(d) An alternative method of testing for the racking load test shall beas  
 
follows:  11  
 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 = 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 an d 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  DVWmust  
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 fac ilitate 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  
12  
 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 iden tical 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 exceed 4 four inches.  
 
814.09(d)(3) Manufacturers shall specify which testing method was usedand 
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 1/2 feet ) pursuant  to 8  
feet, except under the provisions of Section 42 - 4-502 (4)(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 conditioningunits.  
 
10.2 IThe interior  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 have the screen visible 
while driving to aid substitute and new operators.  
 
2251-R-8 11.0 0 Aisle.  
 
11.1 Minimum  aisle  clearance  between  seats  and to all emergency  doors  shall be 12 inches  at seat 
level.  13  
  
 
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-9 12.0 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 the battery  box.  The bBattery  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 placed 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  areacceptable.  
 
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 minutedisplacement.  
 
1411.02(b) Moisture ejection valve: An au tomatic 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: The c Control val ve of the parking brake systemshall 
be designed and constructed to conform with thefollowing:  
 
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 steer ing 
column.  
 
2251-R- 1215.00 Bumpers.  14  
  
 
15.1 Front bumper  shall:  
 
152.01(a) Be at least 3/16 inch thick of pressed steel channel, one piececonstruction with 
minimum of eight - inch width (high), except Type A buses under 14,500 GWVR.  
 
152.01(b) Be of extended design to offermaximum 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 maximumprotection.  
 
152.01(c) Be of sufficient strength to ensure that the front of the bus may belifted by 
means of a bumper type jack withou t permanent deformation of thebumper.  
 
15.2 Rear bumper  shall:  
152.02(a) Be of pressed steel channel or equivalent material, at least 3/16 -inchthick, 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 
the rear- most point of the body at the floor line.  
 
152.02(c)© Be fastened to chassis frame side rails in such a manner as to develop the full 
strength of bumper section from rear or side impact. Bracing materials shall have an 
impact ratio comparable to that of the bumper material and shall be fastened at the 
ends an d radii of the bumper, attached to the side of the frame only, and not to the 
body at any point.  
 
152.02(d) Extend beyond the 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 the 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  
  
 
15.03(b) An American flag sticker, no larger than 7 inches by 11 inches, may be included on the 
rear bumper of the school transportation vehicles, 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 the school 
transportation vehicles.  
 
15.03(d) Bumper stickers and/or signage th at 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 exc eed 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  transportingstudents.  
 
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  theserules  
 
5.07(a)(2)  Lettering “SCHOOL BUS”, as required by section 26.01 ofthese  rules 
 
5.07(a)(3)  Lettering “STOP ON FLASHING RED” as required by  section  26.06of  
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 ofthese 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.  
 
7.77.6School 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 ordecal.  
 
7.87.6It 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  16  
  
 
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.  
 
7.97.6When selling a school transportation vehicle, it is the school district's/charter 
school’s responsibility 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  toregister.  
 
7.11 7.6 All school  transportation  vehicles  must  meet  and contin ue 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 electronic copy) for each ind ividual 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 components 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 17  
 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. Battery tray is to be equipped wit h 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  areacceptable.  
 
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  systemshall 
be designed and constructed to conform with  thefollowing:  
 
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 piececonstruction  
with  minimum  of eight  inch  width  (high),  except Type  A buses  under  14,500 GWVR.  
 
12.01(b)  Be of extended design to offermaximum 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  maximumprotection.  
 
12.01(c)  Be of sufficient strength to ensure that the front of the bus may  belifted  
by means of a bumper type jack without permanent deformation of  thebumper.  18  
 12.212.1  Rear bumper  shall:  19  
  
 
12.02(a)  Be of pressed steel channel or equivalent material, at least  3/16 -inchthick,  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 purchaseroption . 
 
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.  20  
  
 
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 beblack.  
 
16.01(g) The hood of a bus may be painted matte black.  
 
Retro -Refle ctive 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 -ReflectiveNSBY  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  permanentlyattached.  
 
14.02(a)  Type A buses 14,500 GVWR or less may use other metal  ormaterial with  
strength and corr osion 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  listedabove. 
 
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  21  
  
 
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  structuralmembers.  
 
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 theapplication  
plate shall not exceed 5 1/8 inches;  and 
 
14.09(a)(2)  Each emergency exit of the vehicle provided in  accordancewith  FMVSS 
217 shall be capable of operation as specified in that standard during the full 
application of the force and after release of theforce.  
 
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 le ngth of the vehicle's roof 
measured along its  longitudinalcenterline.  
 
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 diagonallydownward  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 beenapplied.  
 
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 theforce  
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  in14.09(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  between32  
degrees Fahrenheit and 90 degrees  Fahrenheit.  
 
14.09(c)(2)  Windows and Doors: Vehicle windows, doors and emergency  exitsare in 
the fully -closed position and latched but  notlocked.  
 
14.09(d)  An alternative method of testing for the racking load test shall beas  
 
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 = 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  
 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  load DVWmust  
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 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.  
 
14.09(d)(2)(B) A two -cycle loading sequence shall be cond ucted, 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 usedand  
submit  appropriate  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  the windshield area,  the left 
front side window to the rear of the driver's vision, and the 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 b lades 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  the manual lever is used, 
no parts shall come together so as to shear or crushfingers. 
 
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 the 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 instructions 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  the floor  or dropping to the 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.  15  
  
 
21.2 EV-Specific  Labeling  
 
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 
unauthorized 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 we ll-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 require ments of 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 recommendation s. 
 
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 propulsion batteries and the requirements to stat ically 
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 adequate 
insulation for the voltage used and for ambient temperatures ranging from - 15 degrees 
Fahrenheit to 120 degrees Fahrenheit . 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 protection against electrical overloads caused by short circuits or 
other excessive current conditions through the use of fuses, cir cuit breakers, and ground 
fault interruption. 
 
21.04(b) The EV Drive System shall have a system for protecting system components 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.  16  
  
 
21.04(c) The EV High Voltage System shall be designed so that when the ignition switch is off or in 
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 ignitio n 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 passenger 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 add ition 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 shall 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  17  
  
 
floor line and cannot come into contact with the road surface.  
 
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 drive selector 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 manual 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 an electric heater control valve.  
 
2251-R- 1922.00Emergency 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   RIGHT SIDE 
EMERGENCY   
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 andmounted with 
enough clearance to permit opening withouttouching 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 servicedoor.  
 
 
 
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  fireextinguisher.  
 
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 e asily read without 
removing the extinguisher from its mountedposition.  
 
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’scontents. 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.  22.03(e)  The rear emergency door shall contain upper and lower glass panels  which  comply  
with FMVSS 205. Glass in the emergency door shall provide the maximum area of 
visibility for the safe operation of the  bus. 
22.03(f)  The emergency window glass shall meet FMVSS 205. Glass shall  be tempered  
unless specified laminated by the  purchase r. 19  
 Contents of the 24 - unit First Aid Kit:  
 
 
 
  
 
   
 
  
 
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.  
23.5 Body fluid cleanup kit: Each All school transportation vehicles 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 vehic les shall carry  the following  emergency  equipment:  
 
20.06(a)  Three (3) emergency triangle reflectors in a securelymounted  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 chemicalfire extinguisher  with  
  a minimum rating of 1A10BC,    
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 
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 
 20  
  
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 in20.04,  
 
23.8  Emergency  equipment  shall be securely  mounted, . Emergency  equipment  shall be clearly  
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  busbody.  
 
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 the 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 the tops of the  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 the type recommended by the manufacturer of floor- covering material. All 
seams 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  orsecured.  
 
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 to prevent water from getting underneath the steptread.  
 
25.5(a) New and emerging coatings may be used in lieu of step treads but shall incorporate 
white or yellow nosing.  
 
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  21  
 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  themanufacturer. 
 
26.2 Any wW elding 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.  
 
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 the fueltank. 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 inside 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 degrees 
Fahrenheit to +10 degrees Fahrenheit and maintaining passenger compartment temperature of 50 degrees Fahrenheit. One of the heaters shall be locate d 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 fro nt 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 H eater cores and fans shall be completely encased but designed to permit servicing  heater  22  
 assembly by removing all or part of thecase.  
 
29.4 Heater hose installation in the engine compartment shall include two shut -off valves shutting 
off coolant  completely  whennecessary.  
 
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.  
 
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 othe r 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 the 
cooling system of the bus to - 30 degrees Fahrenheit tested at normal  enginetemperature.  
 
 
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 the words “SCHOOL BUS” in black letters at least 8 eight inches high 
on both the front and rear of the 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 background pursuant to Rule 36.1. (see 
15.02B)  
 
30.2 School buses shall bear the name of the 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 commun ity, consolidated, and district may  beabbreviated.  
 
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.  23  
 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 orcharter school’s 
governing board, may appear only on the side(s) of the bus in the following 
areas:  
3026 .098(a)(1) The location and securement of the advertising shall have prior 
written CDE app roval.  
 
3026.0 98(a)(2) The signs shall not extend from the body so as to allow ahandhold 
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 o r otherdevice s. 
 
3026.0 98(a)(4)  The signs shall not be placed on side emergency door(s).  
 
3026.0 98(a)(5) Advertising signs shallnot 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 bB attery compartment shall be labeled with the word“Battery”.  
 
30.11 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 conditioningunits.  
 
28.228.1  Interior of bus shall be free of all projections  likely  to cause  injury.  
 
2251-R- 2932.00 Lamps and Signals . 30.12 Multifunction buses shall bear the words “ACTIVITY BUS” in black letters at least 8 inches high on 
both the front and rear of the body. Lettering shall be placed without impairment of its visibility. 
All lettering shall conform to Standard Alphabets for Highway Signs, Series B 2000.  24 32.1   All lamps, signals, reflectors and their installation shall conform to the requirements of the   
 Society of Automotive Engineers, Inc. (SAE) J1945J2442 . 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/taillamps. Two combination 
stop lamps shall have a lens diameter of at least 7 seven 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.  
 
32.3 Interior lamps:  Interior lamps  shall be provided  which  adequately  illuminate  aisle.  A separate 
lamp shall be provided in the  stepwell.  
 
32.4 Back -up lamps:  Back -up lamps  shall  have  a lens diameter  of at least  of minimum  diameter 7 
seven  inch es 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 andtwo 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 discharge 
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 manuallyby 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 areflashing.  25  
  
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 thedual -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 usevisors.  
 
32.7 Type  D rear engine  buses  shall have  two hazard  lamps  each  visible  to the rear when  the engine 
door is open. The l amps 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 no t 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 
operation.  The lLamp  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  the 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 The bBody front  shall be attached  and sealed  to the chassis  cowl  to prevent  the 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 inoperation.  
 
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 s chool activity bus 
standards, designed for transportingstudents.  26  
  
 
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 th e 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(ba)(2) Shall not have the identification ofLettering “SCHOOL BUS”, as  required  by 
section Rule 30.1 26.01 of these  rules  
 
35.017(ca)(3) Shall not have the identification of Lettering “STOP ON FLASHING  RED”  as 
required by section Rule 30.7 26.06 of these rules  
 
35.017(da)(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  
 
35.017(ea)(5) Shall not have a s Stop signal arm, as required by section Rule  41.138.00  of 
these rules   
 
35.017(fa)(6) Shall not be required to have the r Retro -reflective material color,  as 
required by section Rule 36.3 15.02 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 
emergenc y 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 -ReflectiveNSBY material comprising 
background  for lettering  of the front  and/or  rear “school  bus”  signs.  
 
36.4 “Activity Bus” signs: Sides of multifunction bus body shall be marked with white retro -reflective 
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.in white material comprising background for the lettering of the 
front and/or rear of the multifunction school activity  bus. 
 
36.5 Sides of school 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 27  
 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  beself -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 . 
 
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 portableseatsany type of seats that are not secured 
to the floor by the manufacturer. 
 
38.3 Forward -most pupil seat on the right side of the bus shall be located not to interfere with the 
driver's vision. The seat shall not be farther forward than the barrier behind the driver or the 
rear of the 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, inc luding 
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 cloth ing 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 automati cally when  notoccupied.  
 
38.4 School bus student seats and seat spacing shall meet  FMVSS222.  
 
38.5 School bus seat materials shall meet FMVSS  302.  
 
38.6 Integrated child seats shall not be installed at an emergency  exit.  
 
38.7 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.  28  
  
39.3 There shall be a clearance  of at least  2 two inches  between  the steering  wheel  and any other 
surface or control.  
 
2251-R- 3740.00Steps . 
 
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 TypeD) 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  thewood.  
 
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 . 
 
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 thebus.  
 
41.3 The w Wind guard shall be provided to keep the sign in  retractedposition.  
 
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 the 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 six 6 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 Minimu m tire and rim sizes for vehicles with a 10,000 GVWR or greater, shall be in 
accordance with  FMVSS120.  21  
  
44.2 Dual rear tires shall be provided on Type B, C and D schoolbuses 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 thebumper 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 airless 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 the 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 the 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 the 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) J1945 J2202. 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 agrommet.  
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  LiftSystems for 
Motor  Vehicles,  and FMVSS  404,  Platform  Lift Installation in Motor  Vehicles  
 
47.02(b)  A ramp device maybe 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  bluebackground.  
 
47.02(d)  The term wheelchair tiedown and occupant restraint system (WTORS ) isused  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 
whe elchair- seated passengers and shall comply with all applicable requirements of 
FMVSS 222, School Bus Passenger Seating and Crash Protection and FMVSS 302 
Flammability of Interior  Materials.