The data presented on this page is provided strictly for informational and educational purposes. All figures, coefficients, and reference values originate from the CrashMash Software Suite, developed and distributed by Visual Systems Inc. This information is intended to represent ranges of possible values rather than definitive or absolute reference standards. Users are cautioned that results may vary based on situational variables, conditions, and interpretation. 

Forensic Traffic Data Tables

Accel-Decel Rates

Speed Range f ft/sec² m/sec²
Passenger cars - normal acceleration - Less than 20 mi/hr 0.15 4.8 1.46
Passenger cars - normal acceleration - 20 to 40 mi/hr 0.10 3.2 0.98
Passenger cars - normal acceleration - Greater than 40 mi/hr 0.05 1.6 0.49
Passenger cars - rapid acceleration - Less than 20 mi/hr 0.30 9.7 2.96
Passenger cars - rapid acceleration - 20 to 40 mi/hr 0.15 4.8 1.46
Passenger cars - rapid acceleration - Greater than 40 mi/hr 0.05 3.2 0.98
Passenger cars - deceleration (coasting out of gear) - Less than 20 mi/hr -0.01 0.3 0.09
Passenger cars - deceleration (coasting out of gear) - 20 to 40 mi/hr -0.02 0.6 0.18
Passenger cars - deceleration (coasting out of gear) - Greater than 40 mi/hr -0.04 1.3 0.40
Passenger cars - deceleration (engine braking high gear) - Less than 20 mi/hr -0.04 1.3 0.40
Passenger cars - deceleration (engine braking high gear) - 20 to 40 mi/hr -0.05 1.6 0.49
Passenger cars - deceleration (engine braking high gear) - Greater than 40 mi/hr -0.08 2.6 0.79
Medium trucks - normal acceleration - Less than 20 mi/hr 0.10 3.2 0.98
Medium trucks - normal acceleration - 20 to 40 mi/hr 0.05 1.6 0.49
Medium trucks - normal acceleration - Greater than 40 mi/hr 0.03 1.0 0.30
Large loaded trucks - normal acceleration - Less than 20 mi/hr 0.05 1.6 0.49
Large loaded trucks - normal acceleration - 20 to 40 mi/hr 0.03 1.0 0.30
Large loaded trucks - normal acceleration - Greater than 40 mi/hr 0.01 0.3 0.09

Motorcycle Friction

Condition Coefficient (f)
Motorcycles - Free rolling 0.01-0.02
Motorcycles - Front/Rear Full Lockup 0.8-1.1
Motorcycles - Moderate/heavy front brake application with rear wheel lockup fve = (u/2 + u)/2
Motorcycles - Front Wheel Only - Clean, dry surface 0.65-0.70
Motorcycles - Rear Wheel Only - Clean, dry surface 0.35-0.45
Motorcycles - Rear Wheel Only - Soft soil, sand 0.90-1.2
Motorcycles - Rear Wheel Only - Hard soil 0.70
Motorcycle on Side - Asphalt, soft 1.0+
Motorcycle on Side - Asphalt, hard 0.30-0.48
Motorcycle on Side - Portland cement 0.40-0.75
Motorcycle on Side - Concrete 0.45-0.53
Motorcycle on Side - Gravel 0.70-1.0
Motorcycle on Side - Sand 1.5-1.6
Motorcycle on Side - Hard Soil 0.70
Motorcycle on Side - Light scratching 0.30-0.40
Motorcycle on Side - Crash bar contact only 0.20-0.40
Motorcycle on Side - Heavy scratching/gouge 1/4 inch depth 0.50-0.60
Motorcycle on Side - Lubricated surface from motorcycle fluids 0.20
Rider - Rolling/tumbling 0.85-1.0
Rider - Sliding on Asphalt/Portland Cement/Concrete - Riding Leather 0.60-0.70
Rider - Sliding on Asphalt/Portland Cement/Concrete - Polyester 0.70
Rider - Sliding on Asphalt/Portland Cement/Concrete - Cotton/wool (street clothing) 0.70-0.90
Rider - Sliding on Asphalt/Portland Cement/Concrete - Grass 0.79

Vehicle Braking

Vehicle Type Percentage of Braking (%)
Passenger Vehicles - Only front wheels locked 60-70
Passenger Vehicles - Only rearwheels locked 30-40
Passenger Vehicles - ABS equipped; full braking 100+
Motorcycles - Free rolling 0.01-0.02
Motorcycles - Front/Rear Full Lockup 0.8-1.1
Motorcycles - Moderate/heavy front brake application with rear wheel lockup fe = (u/2 + u)/2
Motorcycles - Front Wheel Only - Clean, dry surface 0.65-0.70
Motorcycles - Rear Wheel Only - Clean, dry surface 0.35-0.45
Motorcycles - Rear Wheel Only - Soft soil, sand 0.90-1.2
Motorcycles - Rear Wheel Only - Hard soil 0.70
Straight Trucks 70-80
Loaded Tractor/Semi Trailer (5 axle) [10% steer, 36% drives, 24% trailer] 60-75
Doubles (Cab over Engine tractor and twin 28’s) 80
Trucks 70-80
Concrete Mixers (Caution: Limited Testing) 45-70
Motor Homes (Caution: Limited Testing) 70-80
Commercial Buses - MC-9 (Greyhound style) 70-80
Commercial Buses - Transit (including articulated city buses) 70-85
Commercial Buses - School 70-80
Bobtails - Cab over Engine 30
Bobtails - Conventional 35
Bobtails w/ BP-1 and BP-2 values 80-85
‘Anteaters’ w/ BP-1 92
Frontlines (86+)w/WABCO 6 Channel anti-lock (Westinghouse AirBrake Company) 84-87

Rollover Thresholds

Vehicle Type CG Height In Track Width In Rollover Threshold g
Cars - Sports 18-20 50-60 1.2-1.7
Cars - Compact 20-23 50-60 1.1-1.5
Cars - Luxury 20-24 60-65 1.2-1.6
Trucks - Pickup 30-35 65-70 0.9-1.1
Trucks - Medium 45-55 65-75 0.6-0.8
Trucks - Heavy 60-85 70-72 0.4-0.6
Passenger van 30-40 65-70 0.4-0.6
Tractor-Trailer ~ 5 Axle (Low CG) NaN NaN 0.5
Tractor-Trailer ~ 5 Axle (High CG) NaN NaN 0.25
Semi tanker ~ 5 Axle NaN NaN 0.35
Tanker ~ Liquefied Gas NaN NaN 0.26
Logging Truck NaN NaN 0.23-0.31

Pedestrian Deceleration

Function/Surface Range
Sliding - Grass .45-.70
Sliding - Asphalt - Leathers .60-.70
Sliding - Asphalt - Polyesters, Synthetics .70
Sliding - Asphalt - Cotton, Wool .70-.90
Concrete .40-.65
On Vehicle (Horizontal Movement) .25-.40
Tumbling .85-1.0

Pedestrian Velocities

Age and Sex Pedestrian Velocity (ft/sec) Pedestrian Velocity (m/sec)
Men less than 55 years 5.4 1.65
Men greater than 55 years 5 1.52
Women less than 50 years 4.5 1.37
Women greater than 50 years 4.3 1.31
Women with small children 2.3 0.70
Children 17-24 months - Dawdling 1.9 0.58
Children 17-24 months - Walking 3.3 1.01
Children 17-24 months - Running 4.1 1.25
Children 6-10 years 3.7 1.13
Adolescents 5.9 1.80
Joggers 9.0+ 2.74 +
Pedestrian to turn quickly 180 degrees 0.5 seconds NaN
Pedestrian to turn at normal pace 180 degrees 1.3 seconds NaN
Elderly to turn at normal pace 180 degrees 2-2.5 seconds NaN

Headstrike Speeds

Function/Surface Unnamed: 1 Range
25-30 Mi/hr 40-48 Km/h To hood of vehicle
30-45 Mi/hr 48 - 72 Km/h To lower section of windshield
45-60 Mi/hr 72 - 96 Km/h To upper section windshield
60+ Mi/hr 96 Km/h + To roof section and over

Impact Speeds

Function/Surface Unnamed: 1 Range
10 Mi/hr or greater 16 Km/h or greater Vehicle surface cleaning or scuffing
14-15 Mi/hr or greater 22.4 - 24 Km/h or greater Fracture of weight bearing leg of pedestrian
17 Mi/hr or greater 27.2 Km/h or greater Deformation of hood
45 Mi/hr or greater 72 Km/h or greater Gross vehicle deformation
50-60 Mi/hr or greater 80-96 Km/h or greater Pedestrian dismemberment

Barrier Speeds

Vehicle Weight mph/in Kph / 5cm mph Km/h
1950-2450 0.64 0.52 3.04 4.86
2450-2950 0.65 0.53 2.46 3.94
2950-3450 0.60 0.49 4.04 6.46
3450-3950 0.52 0.42 4.84 7.74
3950-4450 0.47 0.38 4.33 6.93

Audible Levels

Source dBA
Distinguishable 9-10 dBA above threshold
Insertion loss for vehicle 30 dBA
Inside Vehicle: 50 mph ~ Avg Windows closed / no radio 72 dBA
Horn from Locomotive: 100 ft 96 dBA 49CFR229
Interior cab of Truck ~ Avg 85+ dBA

IBFSA (Pty) Ltd expressly disclaims all liability for any loss, damage, or adverse consequence arising from the direct or indirect use, reliance, or application of the data provided herein. By accessing this page, you acknowledge and accept full responsibility for any interpretation or use of the information contained herein.