Collision Repair Glossary

The market value of a vehicle before a collision. Used to calculate the total-loss threshold (typically 70-80% of ACV depending on state and insurer).

Advanced Driver Assistance Systems. Includes adaptive cruise, lane-keep assist, automatic emergency braking, blind-spot monitoring, and parking sensors. Requires calibration after most collision repairs that disturb sensor mounting.ADAS calibration guide →

Securing the vehicle to a frame bench or pulling platform before a structural pull. The OEM-correct standard is a minimum of 4 anchor points to prevent twist during the pull.

National Institute for Automotive Service Excellence. The credentialing body that administers the B-Series collision exams (B2 through B6) through Prometric testing centers.

The composite credential earned by holding active ASE B2, B3, B4, and B5 certifications simultaneously. The highest non-OEM credential for collision technicians.Master roadmap →

The process of breaking liquid paint into fine droplets as it exits a spray gun. Affected by air pressure, fluid tip size, and material viscosity. Poor atomization causes orange peel and dry spray.

One of the three major collision repair estimating software platforms (alongside CCC ONE and Mitchell). Publishes labor times, parts databases, and P-Pages used industry-wide.

The pigmented color layer applied between the sealer and the clearcoat. Modern basecoats are typically waterborne in regulated regions and solvent-borne elsewhere.

A deduction applied to a replacement part's cost because the new part adds life or value to the vehicle (e.g., tires, batteries, brake pads). The customer typically pays the betterment portion out of pocket.

Extending the basecoat into adjacent panels for an invisible color transition. Standard practice for metallic and pearl finishes where a hard edge at the panel seam would show.

A milky or hazy appearance in the dried finish caused by moisture trapped in the film during application on humid days. Cure: use slower reducer or a retarder additive.

Press-Hardened Steel used in modern vehicle pillars, rockers, and bumper beams. Cannot be heat-straightened above the OEM-specified threshold (typically ~1100°F). Usually joined with silicon bronze MIG brazing or STRSW, not standard MIG.Boron rules deep-dive →

Controller Area Network. The high-speed communication network connecting modules in a modern vehicle. A short or open on CAN Bus disables multiple modules at once.Wiring diagram guide →

Certified Automotive Parts Association. A quality certification for aftermarket parts ensuring they meet specific fit, form, and function standards comparable to OEM.

California Air Resources Board. The agency that sets the strictest VOC emission regulations for automotive refinishing in the U.S. Most California shops shoot waterborne basecoat for compliance.

A long-life corrosion-inhibiting wax sprayed into enclosed body sections (rocker panels, pillars, frame rails) after structural repair to restore factory rust protection.

CCC Intelligent Solutions' flagship collision estimating platform. One of the three major industry estimating systems alongside Mitchell and Audatex.

The imaginary vertical plane that divides the vehicle left and right. All width measurements during 3D structural measurement are taken from centerline.

The clear protective top layer applied over the basecoat. Provides gloss, UV protection, and chemical resistance. Typically solvent-borne even in waterborne-basecoat systems.Clearcoat gun comparison →

The flat spiral cable in the steering column that maintains electrical connection between the steering wheel (airbag, horn, controls) and the stationary harness. Must be centered before reinstalling the steering wheel.

Reproducing the existing vehicle color on a repair panel. Modern color match uses spectrophotometers or color match cameras plus formula databases from the paint manufacturer.

An imaginary horizontal plane used as the vertical reference for structural measurement. All height measurements during 3D measurement are taken from datum.

Frame damage where one side is shifted forward and the other rearward, creating a parallelogram shape. Detected with diagonal corner-to-corner measurements that don't match.

Gradual loss of gloss in the finished panel over hours or days after spraying. Causes: under-catalyzed clear, insufficient cure, contamination, or trapped solvents.

The loss in market value a vehicle suffers simply because it was in a collision, even after proper repair. Recoverable in some states as a separate claim against the at-fault party's insurer.

Direct Repair Program. An agreement between a collision shop and an insurance carrier that funnels approved claims to the shop in exchange for compliance with the carrier's repair and pricing standards.

A defect where paint particles partially dry mid-air before reaching the panel, creating a powdery, loose surface. Causes: gun too far, air pressure too high, reducer too fast for booth temperature.

Dual-Phase steel. A modern high-strength steel used in body structures. Like UHSS and boron, has limited heat tolerance (typically ~700°F) and often requires STRSW or weld-bonding per OEM procedure.

Diagnostic Trouble Code. A standardized code stored by the vehicle's modules when a fault is detected. Read with a scan tool during pre-repair and post-repair scans.

Electrocoat primer. The factory-applied corrosion-resistant primer layer between the bare steel and the topcoat layers on a new vehicle.

Electronic Parking Brake. Replaces the traditional handbrake cable with a motor-driven actuator on the rear caliper. Most systems require a scan tool to enter service mode before pad replacement; manual retraction damages the motor.

A two-component primer with excellent adhesion to bare metal and corrosion-resistance. Modern best practice applies epoxy primer to bare steel before polyester body filler.Bare steel procedure →

Tapering the edges of existing paint and primer layers around a repair area to create a smooth transition. Standard sequence steps through 80, 180, 320, and 400 grit per layer.

Circular craters in the wet paint film caused by silicone contamination. Cure: identify and remove the silicone source (often tire dressing or hand lotion) with the manufacturer-recommended wax/grease remover, not by adding fisheye eliminator.Defect cheat sheet →

The time between applied coats during which the solvent (or water) evaporates from the film. Insufficient flash causes solvent pop and mottling on metallics.

A pay system where technicians are paid a published "book time" for each repair task regardless of how long the work actually takes. Rewards fast, accurate work; penalizes troubleshooting time.

The interchangeable nozzle in a spray gun that determines material flow rate. Typical sizes: 1.2-1.3 mm for basecoat and clearcoat, 1.4-1.6 mm for primer-surfacer, 1.6-1.8 mm for sealer.

An I-CAR shop-level designation requiring multiple Platinum-recognized technicians on staff plus ongoing training compliance. Frequently required by OEM-certified shop programs and high-tier DRPs.

Flushing solvent through a spray gun and cleaning the air cap, fluid tip, and external surfaces between materials. Avoid soaking gaskets in lacquer thinner overnight even on modern solvent-resistant seals.

Heating, Ventilation, and Air Conditioning. Tested on the ASE B5 covering refrigerant identification (R-134a vs R-1234yf), pressure interpretation, compressor service, and blower circuit diagnostics.

High-Volume, Low-Pressure. The dominant modern spray gun technology, capped at 10 PSI at the air cap. Required by air-quality regulations in most U.S. states for transfer efficiency.

Inter-Industry Conference on Auto Collision Repair. The industry training organization that publishes role-based ProLevel coursework (ProLevel 1, 2, 3) leading to Platinum recognition and Gold Class shop status.ASE vs I-CAR guide →

Tasks that are automatically factored into a line item's labor time per the estimating system's P-Pages. The opposite of "not-included," which must be billed as separate line items.

Damage caused by the vehicle's own components during a collision, such as the hood pushing back into the cowl or the radiator support hitting the engine.

The ISO-standard polymer identifier molded into plastic parts (TPO, PP/EPDM, PUR, PC, ABS). Each ISO code maps to a specific repair method and surface prep requirement.

A test panel or sprayout card painted with the exact gun settings and reducer planned for the customer's car. Used to confirm color match before committing.

Like Kind and Quality. Used or salvage parts sourced for repairs as a lower-cost alternative to new OEM. Insurance policies may specify LKQ for older vehicles; some state laws require customer disclosure.

Frame damage characterized by shortened wheelbase or compressed rail length. Detected by comparing measurements against OEM specifications.

One of the three major collision repair estimating platforms. Mitchell Estimating provides labor times, parts databases, and P-Pages used across thousands of shops.

Uneven distribution of metallic flakes in the basecoat, creating cloudy patches or stripes. Caused by insufficient flash, wrong overlap, or improper gun distance.Mottling deep-dive →

The federal EPA rule (40 CFR Part 63 Subpart HHHHHH) regulating VOC and HAP emissions from automotive refinishing operations. Sets baseline national VOC limits.

Tasks the P-Pages specify must be itemized separately rather than absorbed into another line item's labor (ADAS calibration, wheel alignment, headlamp aim, pre/post scan, hazardous material disposal).

Original Equipment Manufacturer. The vehicle's original manufacturer (Ford, Honda, Tesla, etc.). OEM repair procedures are the authoritative source for collision repair guidance.OEM procedure hierarchy →

A collision shop that has met a specific manufacturer's certification requirements (training, equipment, facilities). Examples: Ford ProMaster, Honda ProFirst, Tesla Approved, Mercedes Authorized.

V = I × R. The fundamental equation relating voltage (V), current (I), and resistance (R) in an electrical circuit. The ASE B5 typically asks at least one calculation question requiring this formula.

A textured finish resembling the surface of an orange caused by atomization or flow-out issues. Common causes: gun too far, low air pressure, fluid tip too large, reducer too fast.

The percentage of overlap between adjacent spray passes. Standard 50% for solid colors; 75% for metallic and pearl finishes to ensure uniform flake distribution.

Procedure Pages. The "included" vs "not-included" operations documentation embedded in estimating systems (CCC, Audatex, Mitchell). The authoritative reference for what gets bundled into a labor time and what must be billed separately.

Industry recognition earned by completing all required I-CAR courses for a specific role at all three ProLevels (1, 2, 3). Required for Gold Class shop status.

A weld made by drilling a hole through the top panel and welding through it to the panel beneath, typically at original factory spot weld locations. Hole size is typically 5/16 inch (8 mm) for body steel.

A diagnostic scan performed after repair completion to confirm no remaining DTCs and verify all systems function normally. Required by most insurers and OEMs.

The usable time window after activator/hardener is added to a paint material before it begins to cure in the cup. Typically 2 to 4 hours for modern clears at 70°F; shorter at higher temperatures.

A diagnostic scan performed before any disassembly to baseline all DTCs and identify which modules are affected by the collision. Required by most insurers and OEMs.

Damage at the direct point of impact. The visible, obvious damage from the collision (smashed bumper, crushed fender). Contrast with secondary and induced damage.

A high-build, sandable primer applied over filler and epoxy primer to level the surface before sealer and basecoat. Typically applied at 3 to 6 mils film build.

The official testing partner for ASE certifications. Operates testing centers nationwide where ASE B-Series exams are administered on locked-down computers.What to expect at Prometric →

The refrigerant used in most automotive HVAC systems on pre-2018 vehicles. Being phased out as R-1234yf replaces it on newer vehicles. NOT interchangeable with R-1234yf.

The current automotive refrigerant on most vehicles built 2018 and later. Mildly flammable, requires different recovery machines and fittings than R-134a.

Remove and Install. Removing a part to access another repair area, then reinstalling the same part. Different labor allowance than R&R per the P-Pages.

Remove and Replace. Removing a damaged part and replacing it with a new one. Full labor allowance per the P-Pages.

ASE's subscription-based recertification path. Subscribers complete short quarterly quizzes throughout each cycle to maintain credentials without taking full Prometric retakes.Renewal App guide →

Reduced Pressure spray gun technology. Runs slightly higher cap pressure than HVLP with better transfer efficiency on clearcoat. Common modern alternative to HVLP for production painters.

Frame damage characterized by a vertical drop along the rail. Detected by comparing height measurements at the cross-members against published OEM dimensions.

The SATA flagship HVLP/RP clearcoat spray gun and successor to the legendary 5000 series. Known for broad spray patterns and excellent atomization.Spray gun comparison →

A diagnostic device that communicates with the vehicle's onboard modules through the OBD-II port. Used for DTC reading, module programming, ADAS calibration, and EPB service mode.

Damage caused by the energy of a collision transferring through the vehicle's structure. Examples: a buckled roof skin from a front-end hit, or a kinked quarter panel because the floor pan shifted.

The decision (per OEM repair procedure) whether to cut and replace a portion of a panel ("section") or replace the entire panel at the factory joint. Many modern panels have OEM-specified sectioning locations only.

A welding technique using silicon bronze wire at lower heat than steel MIG. Used on boron, UHSS, and other modern high-strength panels where heat damage from standard MIG would compromise the steel's structure.

A handheld device that reads a vehicle's existing color by measuring spectral reflection. Interfaces with the paint manufacturer's formula database to return matching mix recipes.

Small craters or bubbles in the dried paint film caused by solvent trapped under a skinned surface. Caused by insufficient flash between coats or force-drying before full flash.

Supplemental Restraint System. The umbrella term for a vehicle's airbags, seat belt pretensioners, and related modules. SRS wiring is yellow-jacketed and never spliced; service requires battery disconnect plus a manufacturer-specified wait period before any work.

Squeeze-Type Resistance Spot Welding. A modern joining technique using electrodes that pinch panels together and fuse them with controlled current. Increasingly required by OEMs on HSS, UHSS, DP, and boron panels.

Work outsourced to a third-party specialist (wheel alignment, ADAS calibration, glass installation, frame straightening). Billed at sublet cost plus a markup per shop policy.

An amendment to the original estimate covering additional damage discovered after teardown or during repair. Requires insurer (and often customer) authorization before the additional work proceeds.

Technical Data Sheet. The paint or material manufacturer's published product specification document covering mix ratio, pot life, flash time, recoat window, film build, and application parameters.

The state-specific percentage of ACV (typically 70-80%) above which an insurer must declare a damaged vehicle a total loss rather than repairing it.

Thermoplastic Olefin. The most common modern bumper cover plastic. Polyolefin requires adhesion promoter or flame treatment before primer.

Frame damage where one corner of the vehicle is higher than the others. Detected with cross-level checks at the cross-members.

Ultra-High-Strength Steel. Used in modern vehicle structures for occupant protection. Cannot be heat-straightened above the OEM threshold (typically ~700°F); often requires STRSW or silicon bronze MIG braze per OEM.

A vehicle construction type where the body and frame are integrated into a single welded structure. Dominant in modern passenger vehicles. Contrast with body-on-frame (most pickups).

Volatile Organic Compound. The reactive solvent compounds that evaporate from paint as it dries. Regulated by CARB in California and NESHAP federally; the primary driver of the industry shift to waterborne basecoat.

The difference in voltage between two points in an energized circuit. Greater than 0.1V per connection or 0.3V total across a high-current circuit indicates corrosion or poor connection. The single most useful electrical diagnostic technique.

A basecoat where the solvent carrier is partly or mostly replaced with water. Required in California and many Northeast states for VOC compliance. PPG Envirobase HP, Axalta Cromax Pro, BASF Glasurit 90, and Sherwin-Williams Ultra 7000 are the leading systems.Compared in detail →

A surface cleaner used after sanding to remove residual oils, waxes, and silicones before primer or topcoat. Used in conjunction with a clean rag and the manufacturer's recommended product.

Combining structural adhesive with STRSW or MIG plug welds in a single joint. The adhesive distributes load across the panel while the welds provide localized fastening. Increasingly required by OEMs on HSS, UHSS, and DP joints.

A zinc-rich primer applied to mating surfaces before welding. Provides corrosion protection at the joint that would otherwise be inaccessible after the panel is welded in place.

An imaginary vertical reference plane (typically at the rear of the vehicle) that defines the longitudinal "0" point for 3D structural measurement.