02/11/2022
MY EXPERT OPINION REGARDING THE NUNA RAVA INSPECTION
This is an abridged version
The Nuna importer did not inspect the seat when given the opportunity, apart from a visual inspection with the cover removed. They advised this was due to it being dirty. The seat in question was no different from the many seats of private clients or at checking clinics. This so-called inspection was carried out by people only trained as technicians. None of the technician training covers mechanical or design principles of fault analysis. So their opinion is not much more than conjecture.
The Nuna Rava is not designed to be easily disassembled like many other seats are. Therefore, making any repairs by the importer, let alone cleaning by a user.
The parts that can/need cleaning are not accessible by a regular user—complicated by the fact that the manual prohibits a user from disassembling it. So a user cannot comply with any cleaning requirements by the manufacturer other than surface cleaning.
This is due to the seat being several layers, with the adjuster strap and recline mechanism under several of these. Getting to the area of concern took around 4 hours of work. This entailed removing two polystyrene pads and two foam pads as these covered screws. For the seat to be returned to a safe state, it would require replacing these four items. This seat is just not designed to be easily serviced or repaired. Let alone cleaned.
Due to the closed-off design, any food, urine, etc., cannot be entirely removed and cleaned. This is a concern, as suggested by Nuna, that cleanliness was the issue (which it was not). They would have seen the issue if they had had a qualified person to strip the seat down. This means the recline mechanism and other vital areas cannot be reached to be cleaned.
Part of my seat inspection was accurately testing the force required to pull the adjuster strap. On receiving the seat, it had an average pull of over six tests of 6.5kg. For comparison, a brand-new Infasecure averaged 1kg, and an expired Infasecure was 1.2kg. A Diono, in bad shape and not well looked after, mould-damaged harness averaged 2kg. Even when a thorough clean the Nuna only lowered to 3.5kg.
Even at 2kg, this is too high a pull for a parent when the seat is Rear Facing. For a parent or older caregiver, this is a significant concern. The tightness of a harness is a crucial aspect for a child restraint. No matter the seat and cost, it cannot offer optimal protection if it is not correctly set up. A loose harness, especially if uneven, increases the child sustaining an injury or being ejected from the restraint entirely.
Ultimately a car seat should be easy to install and use, including the effort required to pull the harness adjuster strap.
1. This is not an isolated case.
2. Yes, the seat was dirty but no more than a typical seat of this much use. I have seen far worse.
3. The state of cleanliness has nothing to do with the issue that it is a design fault.
4. As a user, you cannot disassemble the seat and cannot thoroughly clean the seat.
5. The design issue means the adjustor moves off a thin centre ridge and jams/wedges itself, which results in the high pull load needed.
6. Every seat will eventually succumb to this issue eventually.
7. I don't believe the seat will last its 10-year design life.
8. The primary issue is the excessive pull required and the likely outcome of an incorrectly tightened harness.
9. It is not fit for purpose and this design fault will always lead to the same issues happening.
What Should You Do
• See a good independent child restraint technician
• Check to see if the chest clip is not causing the uneven pull. This is a common problem with US standard seats
• If it has fraying and is hard to adjust, the retailer needs to be contacted for a refund.
Appendix 1 – Qualifications
1. I am a Forensic Crash Consultancy Ltd director in which I carry out crash analysis, road safety consultancy, and deliver training in crash investigation.
2. I am the NZ director of the Australasian & South Pacific Association of Collision Investigators (ASPACI).
3. I am a member of the United States of America-based National Association of Professional Accident Reconstruction Specialists (NAPARS).
4. I continue to attend courses, seminars and conferences in crash analysis and vehicle-related systems to maintain my currency.
5. I am actively conducting practical crash testing and research for myself and other independent organisations.
6. I have given expert evidence on behalf of the police in both the District and Coroners Courts. I also instructed other officers in preparing and presenting expert evidence in court.
7. I have prepared expert reports for the police for District and Coroners Courts, both as an officer and independent consultant.
8. I hold a level 4 Certificate in Adult Education and specialise in learning and development delivery.
9. I have completed an Incident Cause Analysis Method investigation techniques course.
10. Before my current role, I was the Supervising Instructor for all crash investigation training for the New Zealand Police and a subject matter expert on all aspects of Road Policing.
11. I was a supervisor for the Police Professional Driver Programme.
12. I have 16 years of experience as a Police Officer in the New Zealand Police, eight of which as a specialist traffic officer on the Auckland Motorways. I also worked as a crash analyst on the Waitematä and Counties Manukau Serious Crash Units.
13. During this time, I have attended and investigated approximately 1000 crashes, of which 300 were serious injury and fatal crashes.
14. I have attended and completed the following Crash Analysis & Training Consultants Pty Ltd courses:
RAIS01A Identify and Gather Evidence
RAIS02A Analyse and Report on Evidence
RAIS07A Analyse Commercial Vehicle Collisions
CSI003A Conduct Crash Analysis
CSI006A Gather, Analyse and Interpret Pedestrian and Bicycle-involved crashes
RCIMOT503A Analyse Motorcycle Collisions
RCIPHY505A Apply Physics to Road Crash Investigation
RCICRU501A Conduct Crash Analysis using CRUSH application
15. I have attended and completed the following Accident Analysis & Reconstruction Inc (USA) courses.
Advanced Crash Reconstruction utilising crash data retrieval (airbag module)
Crash Data Retrieval Update Course 2018
Use of Unmanned Aerial Vehicle/Drones (UAV) for aerial forensic mapping 2018
Use of the Pix4D software package with UAV forensic mapping 2018
16. I am qualified to use the Vericom 3000 and 4000 Accelerometers to obtain road surface acceleration measurements and drag factors.
17. I have attended and completed the NZ Institute of Highway Technology Skid Resistance Principles for Road Networks course.
18. As the Supervising Instructor for crash investigation, I was the national trainer for the New Zealand Police, and I developed and instructed the following courses:
NZ Police Forensic Mapping Course
NZ Police Basic Crash Investigation Course
NZ Police Friction Supply Testing and Theory
Crash Analysis Case Review and Expert Witness Code of Conduct
19. I delivered the following courses under licence from Crash Analysis & Training Consultants Pty Ltd (Australia) courses:
RCIREP402A Analyse and Report on Evidence Course
CSI003A Conduct Crash Analysis
CSI008A Analyse Commercial Vehicle Collisions
CSI006A Gather, Analyse and Interpret Pedestrian and Bicycle-involved crashes
RCIMOT503A Analyse Motorcycle Collisions
Bosch Crash Data Retrieval Technician
20. Before my Police service, I spent eight years as an Avionics Technician with the Royal New Zealand Air Force. It is a university-level qualification ranging from electrical to advanced electronic systems and general engineering skills.
21. I am a Child Restraint Technician/Assessor and Trainer. I have been directly involved in child restraint installation and crash dynamics since 2013. I have installed hundreds of child restraints in a private capacity and at roadside checkpoints.
22. In my time with the police, I was the police subject matter expert in child restraints. In addition, I investigated and prepared several reports for other crash analysts concerning serious injury and fatal child restraint crashes.
23. On leaving the police, I continue to provide expert reports to the police.