John R. Yannaccone, P.E.

DJS Associates, Inc.
1603 Old York Road
Abington, PA 19001
Office: 215-659-2010

John R. Yannaccone, PE has been an engineer for over 25 years. For over 20 of those years, he has worked in the forensic engineering field. Most of his work has been related to the investigation and analysis of mechanical failures of various industrial and consumer products. John’s expertise extends to the investigation and analysis of industrial equipment, household appliances and tools, forklifts, ladders, fall protection, machine guards, ropes course elements, wheelchair lifts and occupant restraints, patient lifts, tree stands along with other consumer products. Much of his work has been in the field of occupant protection, primarily in motor vehicles, including child safety seats, seatbelts, seatbacks, airbags and restraint systems.
His work includes involvement in several research projects including a program to improve the safety of occupants in the rear compartment of an ambulance during normal vehicle operations, as well as crashes. John was also involved in the design, testing and development of a seating and restraint system for use in army trucks to provide increased protection to the hazards seen by the military in the field. John has also acted as the test engineer on numerous full-vehicle crash tests conducted in support of litigation.
Additionally, John is a certified Child Passenger Safety Instructor and teaches classes on child passenger safety. A registered professional engineer in several states, John is also a member of numerous professional societies including National Academy of Forensic Engineers, National Society of Professional Engineers, American Society of Mechanical Engineers, among others. He has co-authored approximately two dozen peer reviewed papers and presented at numerous conferences. John is a nationally certified firefighter and a certified vehicle rescue technician. He has additional training in various other emergency services related disciplines. He is also an emergency vehicle driver/operator and has experience related to occupant protection in emergency vehicles.

Areas of Expertise
  • All Terrain Vehicles (ATV)
  • Black Box/Data Recorder
  • Child Safety
  • Consumer Products
  • Conveyors
  • Cranes
  • Design Engineering
  • Equipment & Machinery
  • Fatigue
  • Forensic Engineering
  • Hydraulic Engineering
  • Lifts
  • Machine Guarding
  • Mechanical Engineering
  • Products Liability
  • Professional Engineering
  • Safety Engineering
  • Seat Belts & Air Bags
  • UTV (Utility Vehicles, Side by Sides)

Expert Background
Q: For what area(s) of expertise have you been retained as an expert?
A: Product maintenance, installment and disassembly procedures
Product design issues
Product malfunctions and misuse
Wheelchair tiedowns and restraints (WTORS)
Wheelchair lift failures, procedures and component failures
Machine malfunction, failure and maintenance issues
Garage door malfunction
Facial steamer, blender, and coffee pot malfunction/failure
Chair malfunction and improper maintenance
Supply line failures
Q: What services do you offer? (E.g.: consulting, testing, reports, site inspections etc.)
A: 3D Laser Scanning
Drone/Aerial Documentation
3D Engineering Animations/2D Exhibits
Site & Evidence Inspection
Forensic Evidence Storage
24/7 Rapid Response


Available Upon Request