How to Pass Your Individual Vehicle Approval (IVA)

We understand that when you’re applying for your Individual Vehicle Approval, ensuring your seat set up correctly is critical and not all seats are suitable for this. You do not need specific seats or harnesses in order to pass your approval, but making sure that the seats you’re using are correct is highly important. Through this article, we’ll be discussing the various important factors to consider whilst providing you with links to our specialist sport seat website for products suitable at each point, so you can pass your approval with ease.

Sharp Edges & Interior Projections

All aspects of the design and construction of the vehicle must be such that no immediate danger is present or likely to be present for any person in the vehicle or other road users. This also applies to the vehicle’s seating.

  • GRP Fibreglass Seats: These seats may need to be professionally trimmed to ensure there are no sharp edges at any point of its construction, ranging from the bottom of the base to the top of the headrest. The fibreglass should be smooth & curved at each corner, as to present no danger in an incident. We also recommend seats with standard shoulder supports and without built-in head restraint systems.
  • Steel Frame Seats: These seats are also suitable for an IVA. Steel frame seats are usually made from tubular steel, covered in foam and then trimmed to suit. The key to these seats is to have a suitable headrest.

Seat Fixings & Installation

If you’re using fibreglass seats or steel frame seats, you can install them in two different ways.

  • Fixed Position: You can bolt your fibreglass seats directly into your vehicle in a fixed position. They do not need to slide, as the most important part of this is the type of fixings used and the way in which they are secured. The IVA tester will shake the seat vigorously to ensure it’s firmly fixed to the chassis, so we recommend taking time to get this right.
  • Sliding Position: You can also bolt your seats to sliding runners, which can be fitted to the vehicle allowing forwards and backwards movement. Again, both the seat and the sliders need to be securely bolted into position. We strongly recommend a double locking sliding runner for a more secure installation because single locking runners can have too much ‘play’ on one side, meaning the seat has movement on the unlocked side. Browse our full range of sliding runners over on our website.

Do You Need Headrests?

The simple answer to this is yes. All seats – including fibreglass bucket seats, steel frame bucket seats or sports recliners – must have headrests. It is essential that your seats feature suitable headrests, as you will fail your IVA without them. These can be built into the design of the seat or on adjustable legs like you see in your average road car.

  • As stated by the IVA M1 inspection manual, the head restraint must be securely attached to the seat, appropriately positioned and of adequate strength to fulfil its function.
  • The height of the top of the head restraint above the ‘R-point’ must be at least 700mm, as shown in the diagram taken directly from the IVA M1 inspection manual.

IVA seat diagram

What Do We Recommend? 

Our recommendations will vary depending on the type of vehicle you are putting through an IVA. This is because we are aware that the size & shape of every vehicle and cockpit area will be very different. A Ford GT replica, for example, will be able to install very different seats to a Locost 7 kit car.

  • Your Interior Dimensions: If you know the interior dimensions, of your vehicle, including the space you have available between the door sill & your central tunnel, as well as the space available at the shoulders, then contact us and we’ll give you a list of recommendations to suit your requirements.

Using Harness Belts With Your Seats:

You can use harness belts to pass an IVA. Again, the importance behind these is that they are securely fitted to the body or chassis, at the correct angle for the installed seats, with no exposed or sharp edges that sit within the region occupied by the harness belt webbing.

  • This image, taken from the Schroth harness installation guide, shows the correct angles & positions that the harnesses should be secured at. The angle of each harness is very important, recommended to be no more than 20-degrees downwards, due to the way the forces would be transferred to the seat & your neck during an incident.

Harness belt angle guide

Our Recommended Harness Belts

As we know that not all cars are equal, you may need harnesses cut to different lengths for your own requirements & vehicle setup. With this in mind, we recommend a wide range of TRS Motorsport and LUKE harnesses, made right here in the UK. We work closely with both production teams, so we can ensure you’ll be able to get harnesses cut to the right length & with the right fixings for your vehicle in order to make them a perfect fit.

Creating Your Perfect Setup

Now you’re ready to get the right seat and harness for your vehicle, contact us today & we’ll work with you to ensure you have the perfect setup with all the correct equipment to suit your needs, so you can get your vehicle through its IVA with confidence.