How to Complete the CHP 108A Bus Maintenance and Safety Inspection Form

The CHP 108A form is California’s standardized bus maintenance and safety inspection record, used by carriers operating buses, school buses, youth buses, farm labor vehicles, and similar passenger-transport vehicles to document that a qualified technician has checked each vehicle on the required schedule. You can download it from the CHP website at chp.ca.gov/forms under the “Bus” section, and the form itself notes that it may be reproduced privately since bulk supplies are not available from the CHP.¹ It runs three pages, covers 40 specific inspection items, and functions as a year-long log rather than a single-visit worksheet.

Which Vehicles the Form Covers

The CHP 108A applies to the passenger-transport vehicles listed in California Vehicle Code Section 34500(c): buses, school buses, school pupil activity buses, youth buses, farm labor vehicles, modified limousines, and general public paratransit vehicles.² If you operate one of these, the inspection program under Vehicle Code Section 34501.12 reaches your terminal, and CHP personnel can arrive at any time to verify your records against the fleet.³ The obligation is the same whether you are a public transit agency, a school district, or a private contractor.

How Often You Must Inspect

Before you touch the form, know your interval. This is where carriers most often slip, because two different cycles apply depending on the vehicle:

School buses, school pupil activity buses (SPABs), pupil activity buses (PABs), and general public paratransit vehicles (GPPVs) must be inspected every 3,000 miles or 45 calendar days, whichever comes first. A bus that sits out of service longer than 45 days does not need to be inspected during that idle period, but it must be inspected before returning to service.⁴
Other regulated buses and vehicles under CVC 34500 must be inspected at least every 90 days, or more often if needed to ensure safe operation. Vehicles out of service for more than 90 days must be inspected before returning to the highway.⁵

Emergency exits run on their own clock. Push-out windows, roof exits, and emergency doors must be inspected at least every 90 days regardless of vehicle type, with the inspection documented and retained per federal requirements in 49 CFR 396.3.⁴

The form’s columns run January through December, which fits a carrier on a 90-day cycle neatly. A school bus fleet running heavy routes will often need to inspect more than once a month and will have to attach supplemental records to capture those extra inspections.

Who Can Sign Off

Not just anyone with a wrench can complete the CHP 108A. California Code of Regulations Title 13, Section 1232(e) requires that anyone performing brake inspections, maintenance, repairs, or service on covered vehicles be qualified under federal standards in 49 CFR 396.25.⁴ Under that federal rule, a CDL with an air brake endorsement by itself does not qualify someone as a brake inspector.⁶

You must retain evidence that each person performing inspections meets the qualification requirements. If you contract the work to a commercial garage, that facility can maintain the qualification records on your behalf, but you remain responsible for making sure the documentation exists and is available for CHP review.⁶

Completing the Form

Header Information

At the top, enter the carrier name along with the vehicle’s unit number, year, make, and license plate number.¹ These fields identify which specific vehicle this record belongs to, and they must match DMV and CHP records exactly. A wrong digit on the plate or unit number creates a cross-reference problem during a terminal audit.

The 40-Item Inspection Grid

The core of the form is a grid of 40 inspection items with a column for each month. For each inspection, the technician records the current mileage and marks every item as either “OK” or “DEF” (defective). The 40 items cover the full range of bus safety systems:¹

Item 1, safety equipment: fire extinguisher, first aid kit, reflective warning devices.
Item 2, driver controls: horn, defroster, gauges, odometer, speedometer.
Item 3, interior: driver seat, passenger seats, padding, interior surfaces, floor.
Item 4, visibility: windshield wipers, windows, mirrors, mirror supports.
Item 5, lighting: all interior and exterior lights, signals, reflectors.
Items 6–7, electrical: wiring condition and protection; battery water level, terminals, cables.
Item 8, warning systems: air, oil, temperature, exit, and vacuum warning devices.
Item 9, climate and ventilation: heaters, defrosters, switches, vents.
Item 10, exterior: doors, body, paint, required markings.
Item 11, cooling system: radiator, water hoses, coolant level, leaks.
Item 12, belts: compressor, fan, water pump, alternator.
Item 13, air system: hoses and tubing for leaks, condition, and protection.
Item 14, fuel system: tank, hoses, tubing, pump, leaks.
Item 15, exhaust: manifolds, piping, muffler for leaks and condition.
Items 16–19, engine: mounting and oil accumulation; clutch adjustment; air filter and throttle linkage; starting and charging system.
Items 20–22, hydraulic brakes: adjustment, components, and condition; master cylinder level and leaks; hoses and tubing.
Items 23–27, air brakes: adjustment, components, and condition; one-minute air or vacuum loss test; compressor governor cut-in and cut-out pressure (85–130 psi); primary air tank drain and check valve function; other tanks drained and checked for contamination.
Items 28–29, tires and wheels: tread depth, inflation, and condition; lug nuts, studs, wheel condition.
Items 30–32, braking function: parking brake holds the vehicle; emergency stopping system labeled and operative; brakes do not release after complete loss of service air.
Items 33–35, steering and suspension: steering system mounting, free lash, and components; steering arms, drag links, tie rod ends; springs, shackles, U-bolts, torque rods.
Items 36–40, undercarriage: frame and cross members; drive shaft, universal joints, and guards; transmission and differential mounting and leaks; wheel seal leaks; cleanliness and security.

California Code of Regulations Title 13, Section 1232(b) also requires that every periodic inspection cover at minimum the brake adjustment, brake system leaks, the two-way check valve in dual air systems (tested by alternately draining and recharging primary and secondary reservoirs), tank mounting brackets, belts and hoses, tires and wheels, and steering and suspension.⁴ The 40-item grid covers all of this, but skipping any of these during an inspection leaves the form incomplete regardless of what else was checked. The same regulation requires that excessive oil or grease accumulation be removed and its source corrected, and that every bus be kept clean and free of litter.

Handling a DEF Mark

When a technician marks an item “DEF,” the defect must be corrected before the vehicle operates on public roads. California Vehicle Code Section 34505.5(b) prohibits operating a covered vehicle on the highway until all listed defects have been corrected and the carrier’s authorized representative has signed off on the repair.⁵ The certification line on the form is where that sign-off goes.

Signatures

Each monthly column has a line for the inspector’s signature and date. The signature is a legal attestation that the technician personally evaluated every item on the checklist and recorded the results accurately. A missing signature in any month leaves a gap in the inspection history that CHP will flag.¹

Lubrication and Service Log

Page three is a lubrication and inspection report. It tracks mileage or hours at each service, the date, and the technician who performed the work, with specific fields for oil changes, oil additions, filter changes, transmission and differential service, wheel bearing service, and battery maintenance. Keeping this on the same document as the safety inspection means the bus’s full mechanical history travels together for audits.

Keeping and Producing the Records

Completed CHP 108A forms must be kept at the carrier’s terminal, which Vehicle Code Section 34515 defines as any place where a regulated vehicle is regularly garaged, maintained, operated from, or dispatched, including a private business or residence.⁷ The CHP’s Terminal Manager’s Compliance Checklist references a retention period of one or more years, depending on the applicable Vehicle Code section and regulation.⁸ Since each form covers a full calendar year, holding onto the current year plus at least one prior year is the practical minimum.

Records must be immediately accessible when CHP arrives. Organize files so each vehicle’s complete inspection history can be pulled quickly, because inspectors select a sample based on fleet size, ranging from every vehicle in a one- or two-vehicle fleet up to 20 vehicles for fleets of 91 or more.³

What Happens If Records Are Missing

Vehicle Code Section 34501.12(b) makes the consequence automatic: if a carrier fails to provide vehicles and records when requested, the CHP shall issue an unsatisfactory terminal rating.³ A single unsatisfactory rating gives you 120 days to fix the problem and triggers a reinspection. Three consecutive unsatisfactory ratings cross into what California regulations call “consistent failure,” which opens the door to civil, criminal, or administrative action against the carrier’s permit, operating authority, or license.⁹

A completed, signed, and accessible CHP 108A for every vehicle is what keeps the carrier out of that pipeline. The form is the proof that the inspections happened, that defects were caught, and that corrections were made before the bus went back on the road.

1
California Highway Patrol. Bus Maintenance and Safety Inspection, CHP 108A
2
California Legislative Information. California Vehicle Code Section 34500
3
California Legislative Information. California Vehicle Code VEH 34501.12
4
Legal Information Institute. California Code of Regulations Title 13 Section 1232 – Vehicle Inspection and Maintenance
5
California Legislative Information. California Vehicle Code Section 34505.5
6
Federal Motor Carrier Safety Administration. Part 396
7
California Highway Patrol. Welcome to BIT, the Basic Inspection of Terminals Program
8
California Highway Patrol. Terminal Managers Compliance Checklist, CHP 800D
9
Legal Information Institute. California Code of Regulations Title 13 Section 1233 – Safety Compliance Ratings