The standards, requirements, and procedures set forth in this chapter are applicable to equipment originally installed by the manufacturer or required by federal or State requirement on trucks (over 10,000 pounds GVWR), multipurpose passenger vehicles having a chassis rating greater than 10,000 pounds, truck tractors, commercial buses, and type I school vehicles. Any questions regarding these standards or specifications shall be referred to the Automotive Safety Enforcement Division of the Maryland State Police. Any person constructing or reconstructing a vehicle shall assure the vehicle meets or exceeds all applicable federal and State safety standards. Steering. Inspect the entire steering system including steering, wheel, steering column, lash, linkage, free play, and power steering for missing, loose, damaged, or worn parts. Steering Wheel. The steering wheel shall be inspected to determine whether it is circular (complete rim) and free of cracks, breaks, or objects which will interfere with the safe steering of the vehicle. The inspection will also be made to determine whether the steering wheel is original equipment or equivalent, including diameter. Energy Absorbing Steering Column. Some model vehicles may be equipped with an energy absorbing steering column. This special column was designed to absorb energy by controlling the collapsing of its components. It collapses under impact from wither end of the column—steering gear end or steering wheel end. To determine whether the components are capable of functioning as designed, a careful inspection shall be performed, and include any objects on the steering column. An external examination of either shear pins or collapsible mesh-type material shall also be performed. Coupling. On heavier vehicles, there may be a flexible coupling in the steering column located just above the steering gear, usually known as “rag joint”, “pot joint”, or “U joint”. Lash, Free Play, and Travel. Inspect the steering system to determine whether excessive wear or improper adjustment of the linkage or steering gear exists. The vehicle shall be on a dry surface. If equipped with power steering, the engine shall be running and the fluid level and belt tension shall be within manufacturer's recommendation. (See Figure 3) Linkage. Linkage Play. Excessive free play causes wheel shimmy, erratic brake action and steering control problems. Make sure any looseness detected is not wheel bearing free play. Spring or Torsion Bar Height. Optimum front spring height is established as part of the overall design of front wheel alignment angles. Power Steering. Figure 1—TYPICAL SHEAR CAPSULE LOCATION. Wheel Alignment. There are five basic factors which are the foundation to front wheel alignment: caster, camber, toe-in, steering axis inclination, and toe-out on turns. All are mechanically adjustable except steering axis inclination and toe-out on turns. Overall front wheel alignment can be somewhat grossly indicated by measurement of front wheel toe. Excessive toe-in or toe-out is a general indication that a complete check should be made of all front wheel alignment factors. Rear wheel misalignment on vehicles with fixed rear suspension can be caused by broken or damaged springs, trailing rods, or center bolts and improper toe or camber adjustment on vehicles with independent rear suspension. If during road test there are no undesirable steering or handling reactions, caster and camber check is not necessary. Caster. Caster is the forward or backward tilt, from vertical of the spindle support arm at the top. Improper caster can cause hard steering, low speed shimmy, wander, and brake pull problems. Camber. Camber is the inward or outward tilt of the top of the wheel from vertical. Improper camber can cause erratic tire wear problems, hard steering, and wander. Rear Wheel Alignment. The wheelbase of a vehicle with tandem rear axles is determined by measuring from the center of the front wheel to the midpoint between the tandem axles. When measuring for tracking, the dimensions shall be taken between rear wheel centers. (See Figure 8 or 9) Figure 6—CASTER ANGLES. Agency Note: Not applicable if vehicle specifications indicate different left and right wheel base dimensions. Figure 8—REAR WHEEL ALIGNMENT-TANDEM BUSES. Figure 9—TRUCK WHEEL BASE. Figure 10 — TYPICAL BALL JOINT. Figure 11 — PRE LOADED BALL JOINT. Figure 12 — WEAR INDICATING BALL JOINT. Suspension. Inspect the suspension system for missing, broken, damaged, worn, rusted, or modified wheel bearings, ball joints, control arms, springs, torsion bars, or frame that would affect vehicle stability. Ball Joints. In checking for motion of ball joints, check in accordance with manufacturer's specifications, keeping in mind that the load carrying joint is unloaded in procedures(a) and (b), below, and that a pry bar pressure sufficient only to lift the weight of the wheel assembly is required. If the inspector uses the leverage of a pry bar to exert excessive pressure, he can easily force an apparent ball joint movement and get a false reading. This may result in expensive replacement of perfectly good joints. Therefore, only a 12- to 18-inch pry bar should be used. Ball Joint (wear-indicating). Some manufacturers provide a wear-indicating ball joint to facilitate inspection in which case a visual inspection is made with joints loaded. Ball Joints (nonload carrying). Inspection of nonload carrying ball joints shall also be performed with the joints unloaded. With the vehicle properly jacked, inspect for any noticeable looseness. King Pin or Spindle Bolts. Inspection of king pins or spindle bolts shall be made to determine whether there are any missing, broken, or worn parts that may affect the steering or suspension of the vehicle. Wheel Bearings. Wheel bearings out of adjustment can cause wander, unequal brake action, and noise due to interference of parts. Springs and Torsion Bars. Air Suspension. Some school buses, commercial buses, trucks, and truck tractors may be equipped with air suspension systems. Inspection of the system consists of checking for air leaks, proper height and ride level. CAUTION: The inspector should not use a creeper under the vehicle unless the vehicle is properly jacked and supported. Air Suspension. Retractable Axle (not applicable to school vehicles). Some large vehicles may be equipped with retractable axles. If the axle is the type having independent suspension, the toe shall be checked the same as for the front suspension systems (see Figure 5). Shock Absorbers (if equipped). Lift Axle Air Pressure System. The lift axle shall have a certified air pressure to ensure the minimum load of 12,000 pounds for an evenly loaded vehicle with a gross vehicle weight of 70,000 pounds. Figure 13—BALL JOINT JACKING PROCEDURE. Brake Inspection—Heavy Vehicles. Certain items of special interest shall be considered by the inspector when evaluating the braking on large, heavily loaded vehicles. Safety. The vehicle or combination of vehicles may weigh many tons and too much stress cannot be put upon the safety of the inspector and others when testing the stopping ability of the vehicles. These tests shall be conducted with extreme care in order to prevent possible skidding, jackknifing, load shifting, and overturning. In particular, extreme care shall be used in testing liquid cargo-carrying vehicles under partially loaded conditions because of the sudden surging of the cargo. Practicality. A thorough brake inspection includes the inspection of the inside of the brake assembly. The removal of wheel hubs and drums from large commercial vehicles is difficult because of size and weight problems and extreme care shall be taken to assure they are properly returned to the axle. A thorough examination of the hydraulic, vacuum, or air systems will normally give a fair idea of general condition of the braking system, especially when augmented by a practical performance demonstration. Service Brake Performance Tests. Road. Simple tests and visual procedures. Service brake tests shall be conducted on a substantially level, dry, hard, smooth surface road or area that is free from loose material, oil, or grease. Using the service brake only, the stopping ability of the vehicle shall be tested by one of the following methods: Platform Test. Before attempting inspection by this method, the inspector should be trained and experienced in the use of the equipment and the equipment must have adequate capacity. Dynamic Brake Inspection. This test is for stations equipped with a roller-type brake dynamometer. The rollers should be dry, smooth and free of oil or grease. The equipment indicates both braking effort and imbalance. Brakes on front and rear axles are evaluated separately. Hydraulic System. Tests and visual inspection procedures. Recommended for inspection programs which must accommodate a large volume of vehicles. Results will indicate whether a vehicle has reasonably safe brakes at the time of inspection. The engine shall be running when vehicles are checked with power assisted hydraulic systems. These procedures are applicable to vehicles equipped with hand controls for the physically handicapped. At least one wheel and drum assembly shall be removed from each axle equipped with brakes. On disc brakes only wheel assembly removal is necessary. Any wheel or drum assembly removal shall be on alternate sides. Always inspect a brake assembly which shows evidence of leaking fluid or grease. Do not remove hydraulic wheel cylinder dust boots for inspection. Leakage can be determined by pushing on the outside of the boot. Drums and Discs. Some vehicles have a combination of disc (caliper) type brakes on the front wheels and drum-type brakes on the rear wheels. On vehicles equipped with disc brakes, some drag can be felt when turning the wheel and tire. This drag is not excessive if the wheel can be turned readily with both hands. Brake Linings and Pads. Mechanical Linkage. Includes the parking brake and manual brake controls on vehicles equipped for physically handicapped persons. Vacuum System. Air System—Function: Compressor—Low Indicator—Governor. Air Leakage and Reserve. It may be desirable to install in the system an air gauge (0—150 psi) which has 5 or 10 psi increments, so that small changes in pressure can be more easily observed. Air Brakes—Parking and Emergency Systems. Commercial buses and some trucks may be equipped with hand-operated controls for parking and emergency air brake systems. Actuator Reserve. Emergency Brakes. To avoid confusion between emergency and parking brake systems, refer to definitions (see §T). On vehicles equipped with spring-type emergency brake systems, manual operation of the control valve will also provide an effective parking brake system. Parking Brakes. An emergency brake can also serve as a parking brake but a parking brake is not adequate to serve as an emergency brake. Most large vehicles with hydraulic brake systems and some large vehicles with air brake systems will have a parking brake located on the propeller (drive) shaft. This type of parking brake is usually open and easily inspected. Brake Performance Chart. As of July 1, 1972, all vehicles subject to the regulations of the Bureau of Motor Carrier Safety are subject to the stopping requirements in this Brake Performance Chart except the column pertaining to Emergency Brake System, which are effective on vehicles manufactured after July 1, 1973. This deceleration as measured in brake tests cannot be used to compute the values in Column 4 because it is not sustained at the same rate over the entire period of the stop. The deceleration increases from zero to a maximum during a period of brake system application and brake force build-up. Also, other factors may cause the deceleration to decrease after reaching a maximum. The added distance which results because of a maximum deceleration is not sustained is included in the figures in Column 4 but is not indicated by usual brake testing devices for checking deceleration. There is a definite mathematical relationship between the figures in Columns 2 and 3. If the decelerations set forth in Column 3 are divided by 32.2 feet per second per second, the Column 2 figures will be obtained (for example, 17 divided by 32.2 gives 52.8 percent). Column 2 is included in the tabulation because certain brake testing devices utilize this factor. The decelerations as in Column 3 are an indication of the effectiveness of the basic brakes, and as measured in practical brake testing are the maximum braking decelerations attained at sometime during the stop. The distances in Column 4 and the decelerations in Column 3 are not directly related. Brake system “application and braking distance in feet” (Column 4) is a definite measure of the overall effectiveness of the braking system, being the distance traveled between the point at which the driver starts to move the braking controls and the point at which the vehicle comes to rest. It includes distance traveled while the brakes are being applied and the distance traveled while the brakes are retarding the vehicle. The distance traveled during the period of brake system application and brake force buildup varies with vehicle type, being negligible for many passenger cars and greatest for combinations of commercial vehicles. This fact accounts for the variation from 20 to 40 feet in the numerical values in Column 4 for the various classes of vehicles. The deceleration requirement in Column 3 is the same for all classifications of vehicles except for passenger vehicles, not including buses, because brakes on vehicles in the second, third and fourth classifications are all capable with reasonable maintenance of producing the designated deceleration as measured by brake testing devices. A higher deceleration requirement is warranted for passenger cars in view of United States Department of Transportation/Federal Highway Administration test data. Decelerometers. The method of brake system application and braking distance is not to be confused with the distance indicated by the inertia-type decelerometer and other existing brake testers, which often are purported wrongly to measure the vehicle stopping distance. The pendulum and U-tube decelerometers used for brake testing are instruments scaled to read deceleration or equivalent braking force (sometimes referred to as brake efficiency) in percentages. The principle of the pendulum-type decelerometer is that a pendulum on a vehicle moving at a uniform speed will assume a vertical position. When the vehicle speed is reduced by application of the brakes, the pendulum will swing forward to an angle away from the vertical. The tangent of the angle through which the pendulum moves is directly proportional to the deceleration. Basically, the U-tube fluid-type instrument is a closed glass tube formed in the shape of a U. When vehicle speed is reduced by braking, the inertia of the fluid causes the level in the glass tube to fall. The distance the level of the liquid falls is proportional to the deceleration in feet per second per second, which is read from a scale on the front part of the glass tube. The vehicle will normally pitch because the lines of action of the inertia and braking forces are different. In order to minimize erroneous responses, the decelerometer, if used, should be put as close to the center of the vehicle as practical. Brake Testing Machines. These types of brake testers measure braking force at each wheel. The effectiveness of the brake testers that measure braking force in the testing of vehicles other than passenger vehicles or light trucks is very questionable. The dimensions of these brake testers do not permit practical and reliable testing on combination vehicles. Use should therefore be restricted to two-axle vehicles. The simulated road surface of surface of these machines will occasionally exhibit much higher coefficients of friction than is possible on the highway. Excessive braking should therefore be avoided, be avoided, because braking distribution information is distorted. For drive-on-and-stop test machines, the vehicle is driven on the pads at speeds of 4 to 8 mph. When the brakes are applied at the time the vehicle is moving on the pads, the braking effort at each wheel causes a proportionate movement of the pad against the measuring system. The braking force on the pads is measured by indicating or recording instruments. The roller-type brake testing machine has powered rollers that turn the individual wheels while the brakes are applied in order to measure the brake force developed. Test Wheel Equipment. Any type of fifth or test wheel equipment can be used, if it obtains the following results: It measures the distance within plus or minus 3 percent of the values obtained by the “hot-shot” method, which uses an electrically fired gun. The road speed of the test wheel is measured with a speedometer designed to hold the indicating hand at the speed from which the stop is initiated. The speedometer shall indicate the speed to within plus or minus 2 percent of the speed timed with a stopwatch over a measured mile. Definitions. “Brake system” means a combination of one or more brakes and their related means of operation and control. “Deceleration” means the rate of reduction of the speed of the vehicle, expressed in feet per second per second. “Equivalent braking ratio” means the percentage ratio of the sum of retarding forces developed by each braked wheel to the “as tested” gross weight of the vehicle or combination. “Emergency brake system” means a brake system used for retarding and stopping the vehicle in the event of a malfunction in the service brake system (this function may be performed by the parking brake system or by a portion of the service brake system, or by a separate brake system). “Parking brake system” means a brake system used to hold and maintain a vehicle in a stationary position (a positive mechanical means is employed to hold the brake applied when the vehicle is unattended). “Pedal reserve” as applied to hydraulic, mechanical, or power-assisted hydraulic brakes, means the amount of total pedal travel left in reserve when the pedal is depressed to the brake-applied position (the purpose of the pedal reserve check is to ascertain the degree of the brake adjustment and to demonstrate satisfactory brake actuating system condition). “Service brake system” means a brake system used for retarding, stopping, and controlling the vehicle under normal operating conditions. “Stopping distance” means the distance traveled by a vehicle from the point of application of force to the brake control, to the point at which the vehicle reaches a full stop. Tire Inspection. Reference is made to Figures 17 and 18 for visual aid in determining tire wear. A radial ply tire may not be used with a nonradial-type tire on the same axle. All tires on the steering axle shall be the same size and type of construction. All tires shall be the same size on the same axle. Wheel Inspection. The fuel system includes the fuel tank, fuel pump, and necessary piping to carry the fuel from the tank to the carburetor or to the injection system. The exhaust system includes the exhaust manifold, and all piping leading to and including the muffler, catalytic converter, resonator, and the tail piping. This regulation represents the current recommendations of the Vehicle Emissions Inspection Panel of the Motor Vehicle Manufacturers Association, Inc., regarding engine maintenance inspection required to minimize vehicle emissions. This section is advisory and is primarily related to 1968 and later models. The inspection of emission control systems applies only to spark ignition engines, not to diesels. This regulation is applicable to school vehicles only. Crankcase Ventilation. The ventilation system of the crankcase is common to engines using either an “air injection” system of control or an “engine modification” system. The engine should be warm and running at idle before inspection of vent system. Air Injection Type—Idle Speed and Timing. An air injection-type exhaust emission control system can be identified by an air pump and a distribution system to the exhaust ports. The air pump is normally driven by a belt off the crankshaft or water pump pulleys. Only the plumbing, idle speed and ignition timing need be inspected. Reference is made to the Idle Setting Limits Table I. Engine Modification Type—Idle Speed and Timing. An “engine modification” control system may be most easily identified as one without an air pump. The emissions are primarily controlled by engine design. The items to be inspected are vacuum, idle speed, ignition timing, and idle air-fuel mixture by measuring the carbon monoxide (CO) content of the exhaust. Refer to Table II, Idle Setting Limits. Engine Modification-Type Fuel Mixture (Carbon Monoxide). The carbon monoxide (CO) concentration in the exhaust of most vehicles may not be more than 3 percent. Be sure that the testing is done by an experienced operator and that the exhaust analyzer is properly calibrated. Bumpers shall be inspected for broken or missing parts, abnormal protrusions, sharp edges, or conditions that could be hazardous to persons. The bumpers shall be securely mounted to the vehicle and be capable of absorbing a reasonable degree of impact. Every truck with a GVWR over 10,000 pounds, except truck tractors and vehicles engaged in drive-away/tow-away operations, which is so constructed that the body or the chassis assembly, if without a body, has a clearance at the rear end of more than 30 inches from the ground when empty, shall be equipped with a permanent rear bumper or metal frame attached to the underside of the rear of the truck. The bumper or frame may not be any wider than the width of the truck, and may not be more than 30 inches above the highway when moving and shall be constructed of heavy gauge steel. The maximum transverse distance from the widest part of the vehicle at the rear to the bumper or metal frame may not exceed 18 inches. The frame shall be constructed so as not to interfere with lights or other warning devices. Any truck so constructed and maintained that the body, chassis, or other parts thereof afford the protection required by this section shall be deemed in compliance with this section. The provisions of this section do not apply to vehicles where the installation of the required bumper or metal frame would prevent operation of the vehicle to secure its designated purpose. A person may not operate, cause or permit to be operated any bus or truck on the highways of this State unless it is equipped with suitable metal protectors or substantial flexible flaps behind the rearmost wheels of the vehicle to prevent the projection of rocks, dirt, water, or other substances to the rear and to minimize side spray. This regulation does not apply to any farm tractor or any vehicle registered as a farm truck or to uncoupled truck tractors or other vehicles where the construction is such that complete freedom around the wheel area is necessary to secure the designed use of the vehicle. Procedures Reject Vehicle If: A. The protectors or flaps shall have a ground clearance of not more than one-third of the horizontal distance from the bottom edge of the protector or flap to the centerline of the axle, provided, however, that no protector or flap need becloser to the ground than 6 inches under any condition of loading. The protector or flap shall extend laterally at least the width of the tire or tires being protected. A. Measurement A is longer than 1/3 the length of Measurement B and the vehicle is not equipped with flaps (see Figures 20 and 21).B. Protector or flap does not extend laterally at least the width of tire or tires.C. Protectors or flaps not securely attached to the vehicle. B. If any truck or bus is so designed or constructed that the objectives of this regulation are accomplished by reason of fender or body construction or other means of enclosure, either permanent or temporary, then the requirements of this regulation have been satisfied. Figure 20—REAR WHEEL PROTECTOR FLAP REQUIREMENTS. Figure 21—REAR WHEEL PROTECTOR FLAP REQUIREMENTS. Fender inspection shall include condition, mounting, and coverage of wheels and tires. If the body of the vehicle does not provide coverage, the vehicle shall then be equipped with suitable metal protectors or substantial flexible flaps behind the rearmost wheels of the vehicle. Procedures Reject Vehicle If: A. Fenders shall be securely attached to the vehicle and inspected for tears, sharp or jagged edges, sufficient coverage of the wheel and tire both from the body outward and to the front and rear of tires and wheels. Fenders may be extended outward to compensate for tire and wheel changes provided these extensions: A. (1) Fender has tears, sharp or jagged edges. (2) Fender is not securely fastened to the body. (3) Fender does not extend outward from the body to cover the top of the wheel and tire. (1) Provide required coverage of wheels and tires; (4) The rear of all fenders do not extend downward to the horizontal centerline of the wheel. (2) Are constructed of substantial materials; (3) Are securely attached to fenders the fenders; (5) Fronts of all fenders do not extend forward from the vertical centerline of the wheel to at least within a 45-degree angle of the horizontal centerline. (4) Have all edges rolled to eliminate sharp or jagged edges;; (5) Do not contact tires during different vehicle attitudes; (6) Fender has been extended downward to compensate for suspension modifications. (6) On trucks and truck tractors, applies only to front fenders and rear fenders when equipped. (7) Fender is missing. (8) The vehicle is not equipped with flaps behind the rear wheels when required. Figure 22—FENDERS. Body exterior components and sheet metal parts, if damaged or dislocated so that they project from the vehicle to present a safety hazard to occupants, pedestrians, or other vehicles, may be cause for rejection of the vehicle. Procedures: Reject Vehicle If: A. Protruding Metal: Inspect for torn metal parts, moldings, rub rails, etc., which may protrude from vehicle. A. (1) Body components or sheet metal are subject to rejection if a condition exists which is hazardous to occupants, pedestrians or other vehicles. (2) Torn metal, broken glass, or other loose or dislocated parts protrude from the surface of the vehicle which is hazardous to occupants, pedestrians, or other vehicles. Figure 23—SCHOOL VEHICLE CONSTRUCTION AND SEATING. General Lamp and Reflector Inspection. This includes all original equipment, exterior lighting plus whatever lights are authorized. School vehicles have special marking and lighting to assure their identity. Refer to diagrams of front and rear views (Figures 27 and 29). Preparation for Headlamp Aim Inspection. Preparation for headlamp and aim inspection is to be done by owner of vehicle before inspection. Frame leveling and wheel alignment inspection is done before inspection. Frame leveling and wheel alignment inspection is done at the station. Any one of the items listed below can affect the inspection results and may cause rejection of the vehicle. To prevent this and reduce inspection time, the owner should have the first three items completed before inspection. Headlamp. High Beam. Vehicle shall be equipped with either the dual headlighting system consisting of four 5 1/4-inch diameter units, two of which shall be No. 1 and two of which shall be No. 2; or four 6 1/2 × 4 1/2 inch rectangular units, two of which shall be No. 1A and two of which shall be No. 2A; four 5.93 × 3.64-inch rectangular-type F units, two of which shall be LF units and two of which shall be UF units; or a single headlighting system consisting of two 7-inch units; or two 8 × 5 inch rectangular units; or an approved bulb and reflector-type system. All units bearing the marking No. 2 shall be inspected and aimed on low beam. All units bearing the marking No. 1 or no number shall be inspected and aimed on high beam. Headlamp inspection and aiming by the photoelectric-optical method, not applicable to school vehicles, requires a level area sufficient for the vehicle and test equipment. The test equipment shall be accurately calibrated to the floor and accurately aligned to the vehicle. Additional lighting information is contained in §§E, F, and G (limits are in inches at 25 feet). Labeling requirements for sealed beam headlamps manufactured on or after July 1, 1979: 5 3/4 inch type 1-1C1, type 2-2C1; 6 1/2 inch by 4 1/2 inch type 1A-1A1, type 2A-2A1; 7 inch type 2-2D1; 8 inch by 5 inch type 2B-2B1; type F 5.93 inch by 3.64 inch—low beam—LF, high beam—UF. Type F units require a special aimer adapter and must be aimed in accordance with the manufacturers' recommended procedures. Bulb and reflector-type headlamps currently approved contain a 9004 Sylvania bulb in a normal reflector unit or an H-4 bulb in a sealed reflector unit. Sealed reflector units contain a glass bubble which encases the bulb when in place which can be detected by removing the bulb and determining if the bubble exists. Low Beam. Inspect the low beam headlamp in the same method as indicated for high beam. Always inspect the following sealed beam units on low beam only: 5 3/4 inch diameter or 6 1/2 × 4 1/4 inch rectangular marked type 2 or 2A and 7 inch diameter or 8 × 5 inch rectangular marked type 2 or 2B. Agency Note: Labeling requirements for sealed beam headlamps manufactured on or after July 1, 1979: 5 3/4 inches Type 1—1C1, Type 2—2C1; 6 1/2 inches by 4 1/4 inches Type 1A—1A1, Type 2A—2A1; 7 inches Type 2—2D1; 8 inches by 5 inches Type 2B—2B1 Headlamp—Applicable School Vehicles Only. To compensate for the various conditions of loading encountered during inspection, the frame or body floor shall be made level before checking. This will provide a standard condition for inspecting all vehicles and may be accomplished by using a combination of blocks under the rear wheels or a lifting device (jack) or both for the front end. A spirit level may be laid along the frame side member. Place vehicle in a darkened location of sufficient size for the vehicle and an additional 25 feet from lamps to screen. Level the vehicle frame as described in §C(1). The vehicle shall be located accurately in front of the screen. An approved marked screen and adequate test area are required. Inspect the low beam headlamp in the same method indicated as for high beam. Always inspect the following sealed beam units on low beam only: 5 3/4 inch diameter or 6 1/2 × 4 1/4 inch rectangular units marked type 2 or 2A and 7 inch diameter or 8 × 5 inch rectangular units marked type 2 or 2B. Figure 30—AIMING SCREEN BEAM PATTERN-HIGH BEAM. Fog Lamp and Auxiliary Driving Lamps. If a vehicle is equipped with either fog lamps or auxiliary driving lamps they shall be properly aimed. Fog lamps shall be mounted on the front of the vehicle at a height not more than 30 inches or less than 12 inches above the level surface on which a vehicle stands. Only two fog lamps are allowed by law. Auxiliary driving lamps shall be mounted on the front of the vehicle at a height not more than 42 inches or less than 16 inches above the level surface on which the vehicle stands. Only two auxiliary driving lamps are allowed by law. The mounting heights of auxiliary driving lamps do not apply to emergency vehicles. Definitions. “Asymmetrical beam” (nonsymmetrical) means a beam in which both sides are not symmetrical with respect to the median vertical plane of the beam. All lower beams are asymmetrical. “Back-up lamp” means a lamp used to provide illumination behind the vehicle, and to provide an indicator when the vehicle is in reverse gear. “Clearance lamp” means (on trucks and buses 80 inches or more wide) a lamp which shows to the front or rear of a vehicle, mounted on the permanent structure of the vehicle as near as practicable to the upper left and right extreme edges to indicate overall width and height of the vehicle. “Cornering lamp” means a steadily burning lamp used when the turn signal system is operating to supplement the headlamps by providing additional road illumination in the direction of the turn. “Driving lamp” means the auxiliary lamp or lamps that may be used to supplement the upper beam of the regular headlamps. “Emergency warning lamp” means a lamp which provides a flashing light to identify an authorized vehicle on an emergency mission. The emergency signal may be an oscillating lamp, a rotating beacon, or pairs of alternately or simultaneously flashing lamps. “Fog lamps” means a lamp which may be used with the lower beam headlights to provide illumination under condition of rain, snow, dust, or fog. “Hazard warning lamp” means a turn signal lamp which flashes simultaneously to warn of the presence of a vehicular hazard. Headlamps. Five and 3/4 Inch Round Sealed Beam Unit. “Type 1 sealed beam unit” means a sealed beam unit 5 3/4 inches in diameter having a single filament and providing only an upper beam distribution of light. This unit is identified by a number 1 on the lens and is aimed on the upper beam. “Type 2 sealed beam unit” means a sealed beam unit 5 3/4 inches in diameter having two filaments, one filament providing the lower beam and one filament providing fill-in light for the upper beam. This unit is identified by a 2 on the lens and is aimed on the lower beam. “Seven Inch Round Sealed Beam Unit” means a sealed beam unit 7 inches in diameter providing an upper and lower beam. This unit is identified by a number 2 on the lens and is aimed on the lower beam. If there is no identifying number on lens, it means a sealed beam unit 7 inches in diameter providing an upper and lower beam. It is aimed on the upper beam. “Eight Inch by 5 Inch Rectangular Sealed Beam Unit” means a sealed beam unit providing an upper and lower beam. This unit is identified by a number 2B on the lens and is aimed on the lower beam. Six 1/2 by 4 1/2 Inch Rectangular Sealed Beam Unit. Type 1A—means a sealed beam unit having a single filament and providing only an upper beam distribution of light. The unit is identified by a number 1A on the lens and is aimed on the upper beam. Type 2A—means a sealed beam unit having two filaments, one filament providing fill-in light for the upper beam. This unit is identified by a number 2A on the lens and is aimed on the lower beam. “Bulb and reflector headlamps” means a lamp assembly providing an upper and lower beam light by means of a replaceable bulb. These lamps are aimed on lower beam. They shall be capable of producing at least 5,000 candlepower output on upper beam and 3,500 candlepower output on lower beam, and must be capable of being aimed. 5.93 x 3.64 Inch Rectangular Sealed Beam Unit. Type LF—sealed beam unit having a single beam filament and providing only a lower beam distribution of light. The unit is identified by the designation LF on the lens. A special aimer adapter is required for aiming, and aiming must be accomplished in accordance with the manufacturer's recommended procedures. Type UF—sealed beam unit having a single beam filament and providing only a upper beam distribution of light. The unit is identified by the designation UF on the lens. A special aimer adapter is required for aiming, and aiming (if applicable) must be accomplished in accordance with the manufacturer's recommended procedures. “Headlamp lower beam” means a distribution of light so directed as to avoid glare in the eyes of oncoming drivers while providing illumination ahead of the vehicle and intended for use in congested areas and on highways when meeting other vehicles within a distance of 500 feet. “Headlamp upper beam” means a distribution of light intended primarily for distant illumination and for use on the open highway when not meeting other vehicles. “Identification lamps” (on trucks and buses 80 inches or more wide) means lamps used in groups of three, in a horizontal row, which show to the front or rear or both, having lamp centers spaced not less than 6 or more than 12 inches apart, mounted on the permanent structure as near as practicable to the vertical centerline and the top of the vehicle, to identify certain types of vehicles. “Indicator lamp” means a lamp visible to the operator of a vehicle that indicates: Appropriate electrical circuits are in operation; Malfunction of vehicle performance; and Requirement for remedial action by the operator of the vehicle. “Lane changer” means a device, usually incorporated in the turn signal switch which will actuate the turn signal lamps when held by the driver. It is intended for momentary use for signaling a lane change. When released by the operator, it will return to neutral and de-activate the signal lamp. “License plate lamp” means a lamp used to illuminate the license plate on the rear of a vehicle. “Operating units or switches” means devices by which the functioning lamps are controlled. “Parking lamp” means lamps used to designate the front of a parked vehicle. “Passing lamp” means an auxiliary lamp or lamps that may be used to supplement the low beam of a standard headlamp system. It is not intended for winding roads or congested city areas. “Reflective devices” means a device used on vehicles to give an indication to an approaching driver by reflected light from the headlamps of approaching vehicles. “SAE Lighting Identification Code” means a series of standardized markings for lighting devices which a manufacturer or a supplier may use to mark his product to indicate the SAE lighting standard or standards to which the device is designed to conform. The code is not intended to limit the manufacturer or supplier in applying other markings to the devices. “Sealed beam headlamp assembly” means a major lighting device used to provide general illumination ahead of the vehicle. It consists of the following: One or more sealed beam units (bulb assembly); Means for mounting securely to the vehicle; Means to permit required aim adjustment. “Sealed beam unit” means an integral and hermetically sealed optical assembly with the name “Sealed Beam” molded in the lens. “Side marker lamp” means a lamp on the left and right sides, beamed to the side, and intended to indicate vehicle length. They are located near the front and rear on each side and, for vehicles over 30 feet in length, are also located at the midpoint (intermediate side marker). “Stop lamp” means a lamp giving a steady warning light to the rear of a vehicle, to indicate the intention of the operator of the vehicle to reduce speed or stop. “Symmetrical beam” means one in which both sides are symmetrical with respect to the median vertical plane of the beam. Lamps having symmetrical beam are: Five 3/4 inch diameter type I; Five 3/4 inch diameter type 2 (upper beam filament); Six 1/2 by 4-1/4 inch type 1A; Six 1/2 by 4-1/4 inch type 2A (upper beam filament); Eight by five inch type 2B (upper beam filament); All 7 inch diameter units (upper beam filament). “Tail lamp” means a lamp used to designate the rear of a vehicle. “Turn signal lamp” means a lamp which provides a flashing warning light to indicate the intended direction of the turn. SAE Identification Code (J759C SAE Handbook). The following list is an identifying code for lights and signaling devices: All equipment for testing headlamps shall comply with the Society of Automotive Engineers Recommended Practice for Headlamp Inspection Equipment. Headlamp Testing Machines. Headlamp Testing Machine. When a headlamp testing machine is used, it shall give results equivalent to those obtained using a screen. It shall be in good repair and adjustment, and shall be used in accordance with the manufacturer's instructions. A machine using a photoelectric cell or cells to determine aim should also have a visual screen upon which the beam pattern is projected proportionally to its appearance and aim on a screen at 25 feet. The visual screen shall be plainly visible to the operator and have horizontal and vertical reference lines to permit visual appraisal of the lamp beam. Mechanical Aimer (applicable to school vehicles only). When a mechanical aimer is used, it shall be in good repair and adjustment, and shall be used according to the manufacturer's instruction and shall be calibrated to the slope of the floor on which the vehicle stands. Screen (applicable to school vehicles only). When a screen is used, it should be 5 feet high x 12 feet wide with a matte white surface well shaded from extraneous light, and properly adjusted to the floor on which the vehicle stands. Provisions may be made for moving the screen so that it can be aligned parallel with the rear axle so that a horizontal line drawn perpendicularly from the centerline of the screen will pass an equal distance midway between the two headlamps. The screen shall be provided with a fixed vertical centerline, two laterally adjustable vertical tapes, and one vertically adjustable horizontal tape. Electrical System. To save time, the inspector should develop his own plan or sequence for checking miscellaneous electrical items, many of which can be inspected while inspecting other items. Seats, Stanchions, Rails. Visors and Defroster. Sun visors shall be located in front and above the driver and passenger positions. Heaters, Step or Stepwell, and Vents. Fire Extinguisher, First Aid Kit, and Tire Chains. Every school vehicle shall be equipped with a dry chemical fire extinguisher, and first aid kit container mounted in plain view in the driver's compartment, and where applicable, tire chains. Warning Devices. Color. Signs and Lettering. Retro-Reflective Tape. Identification. Inspect for presence, size, and condition of required or permitted identification. Outside Mirrors. Every vehicle shall be equipped with an outside rearview mirror on the driver's side providing a view of the highway for a distance of at least 200 feet to the rear. Every school vehicle shall be equipped with at least one convex mirror, not less than 7-1/2 inches in diameter, which shall be firmly mounted on the left front corner forward of the seated driver so that he may observe a reflection of the road from the front bumper to a point where direct observation is possible. One outside rearview mirror on each side of a school vehicle shall be mounted forward of the driver's seat and have an area not less than 50 square inches (minimum 5 inches wide by 10 inches high). Additionally on school vehicles manufactured after December 31, 1972, there shall be on each side of the vehicle a convex mirror of not less than 20 square inches of reflective surface. The convex mirrors may be incorporated in the plain rearview mirror provided the plain view reflective area is not reduced, or they may be mounted independently. Either type shall be independently adjustable. Inside Mirrors. Every vehicle shall be equipped with an inside rearview mirror except as noted in §B(1) and (2). The inside rearview mirror shall be clear view glass and adjustable, and provide a clear stable reflected view 200 feet to the rear. School vehicles shall be equipped with a mirror 6 inches by 30 inches, metal backed, framed with rounded corners, and firmly mounted as far forward as possible, and provide a clear stable reflected view of the road surface to the rear of the vehicle for a continual distance beginning not more than 200 feet to the rear. Safety glazing material is marked with the manufacturer's distinctive designation or trademark, model number and the letters “AS” followed by a number from 1 through 16B, which indicates where the glazing may be used on the vehicle. Safety glazing material also has the symbol “DOT” (Department of Transportation) and a manufacturer’s code mark that the NHTSA (National Highway Traffic Safety Administration) assigns to the manufacturer. Any questions regarding glazing shall be referred to the Automotive Safety Enforcement Division of the Department of State Police. Proper Marking and Operation. Signs and Materials on Windshield or Windows. Inspect all glazing for unauthorized material or conditions that obscure the driver's vision. Post Manufacture Window Tinting. Definitions. “Acute area” means the windshield area 8 inches wide by 5 inches high, located directly in front of the driver, centered vertically on the steering wheel of the vehicle and horizontally in the center of the critical area. “Cloudiness” means any degree of visible discoloration or separation, except tinting that does not affect clear vision. “Critical area” means the normal windshield wiper sweep, except the area obscured by the hood, fenders, or rearview mirror. “Discoloration” means a condition which impairs the transparency of the glazing. “Non-critical area” means all windshield area outside the critical area. “Normal windshield wiper sweep” means the area of the windshield cleaned by the windshield wiper, excluding the return position on both passenger's and driver's sides. Glazing Damage. The windshield wipers shall be inspected for operation, control, condition of blades and arms, or any missing part. Inspection shall consist of operation and presence of catches and safety catches, insuring that the hood covers at least the top part of the engine compartment; and if equipped with an air scoop or bubble, it does not extend higher than 1/3 the vertical height of the windshield. Inspection of doors, handles, latches, and hinges applies to all vehicles originally manufactured with doors and all other vehicles which are equipped doors. Doors—Service, Emergency (applicable to school vehicles only). Service doors may be split-type, sedan-type, or jackknife-type with vertical closing edges covered with flexible material. Floor and trunk pans shall be inspected for holes or rusted and weakened conditions. Speedometer, odometer, or hubometer will be inspected to determine if they are connected and operable, the dial and calibrations are legible, and calibrated in miles or kilometers. The vehicle owner shall establish a preventive maintenance program recording inspection, repairs, and maintenance by vehicle number, and include at least annually a complete preventive maintenance inspection, to assure that each vehicle is in compliance with all sections of this handbook pertaining to school vehicles. When the wheels have been removed for inspection or maintenance, and after the wheels have been replaced, the vehicle shall be test-driven to assure there is no brake imbalance before the vehicle is released for pupil transportation. Before September of each year, the Administration shall determine that the annual preventive maintenance inspection on each vehicle has been performed within the previous 12 months, repaired or replaced systems or parts are operating properly, and the condition of the vehicle is in accordance with the established standards. The Administration may require a wheel or wheels to be pulled by the vehicle owners or mechanic, to verify condition and repair of brake and other systems. In the event of a change of vehicle ownership and before the vehicle is authorized to transport school children, the Administration may require a preventive maintenance inspection and accomplishment of any maintenance found necessary. Preventive Maintenance Inspection. Regular Inspection. Regular inspections shall be performed twice annually as required. This regulation does not apply to a: Class K (farm area) vehicle as defined in Transportation Article, §13-935, Annotated Code of Maryland; Construction vehicle working within the confines of a public works construction work project site as outlined in the construction project's plans and specifications, provided the distance travelled does not exceed 1 mile or the distance specified in an extension granted by the Maryland Department of Transportation; Construction vehicle or mining equipment while crossing a highway between construction or mining sites; or Vehicle, within the Port of Baltimore for a distance not to exceed 1 mile, carrying a load of loose material between a stockpile or storage facility and a vessel docked at the Port. This regulation applies to: Any vehicle, not otherwise exempted, manufactured on or before July 1, 1990 and carrying loose material if any part of the loose material is within 6 inches of the top of any bed enclosure it touches; Any vehicle, not otherwise exempted, manufactured after July 1, 1990 regardless of the loading of loose material; After January 1, 1992, any vehicle not otherwise exempted and regardless of loading of loose material. The requirements of this regulation apply only to the issuance and certification of a safety equipment repair order and do not apply to a complete inspection required upon sale or transfer of ownership of a used vehicle. A safety equipment repair order may be certified only if the cover is present, fully covers the top of the bed, and meets the requirements of this regulation. Transportation Article, §§12-104(b), 23-101—23-105, and 24-106.1, Annotated Code of Maryland Effective date: Chapter revised effective October 3, 1980 (7:20 Md. R. 1880) Chapter revised effective October 31, 1988 (15:22 Md. R. 2557) Regulation .02 amended effective October 9, 1995 (22:20 Md. R. 1544) Regulation .05 amended effective April 1, 1991 (18:6 Md. R. 686) Regulation .06 amended effective April 1, 1991 (18:6 Md. R. 686) Regulation .10 amended effective April 1, 1991 (18:6 Md. R. 686) Regulation .14 amended effective February 1, 2012 (39:1 Md. R. 18) Regulation .16 amended effective April 1, 1991 (18:6 Md. R. 686); August 21, 2000 (27:16 Md. R. 1526); February 1, 2012 (39:1 Md. R. 18) Regulation .19 amended effective February 1, 2012 (39:1 Md. R. 18) Regulation .23 adopted effective April 1, 1991 (18:6 Md. R. 686)