Footing is a critical issue in arenas and many surfaces have been used including:
  • sand
  • sand / fibre mixes
  • rubber of various types and mixes

Horses create dust by grinding up the surface every time a hoof hits the ground. Thus all horse arenas need some form of dust control. Control methods include:
  • water
  • orange oil
  • wax / surface additives
  • commercial dust suppressants

Sand

Most arena surfaces contain a significant proportion of sand. Sand is cheap, available and a good starting point for a working surface. To reduce the amount of dust you introduce in to your arena, a washed SiO2 (Silica Dioxide) sand should be used. This type of sand is strong and tends to resist wear and being washed the smaller particles that are inclined to become airborne are already removed.

The grade or mix of sand depends strongly on your requirements. Some factors to consider:
  • When you mix grades of sand they will tend to compact faster and more completely. A single grade of sand will tend to compact least.
  • Very fine sand is not suitable for outdoor arenas especially in high wind areas: it blows and washes away.
  • Finer sand tends to retain water better than coarser sand.
Sand is almost always mixed with something to change its properties. For instance, wood fibre is commonly used to increase the water retention and cause the particles to slide less making the surface less deep.

A useful fact for ordering sand is that 1 cubic metre weighs approximately 1.5 tonnes

Water

Water is a common, simple and environmentally and horse friendly solution to dust control. However, it does require a large supply of water and time (our 20 by 40 arena required 30 minutes of watering per day on days the arena was used to control both the dust and provide a sufficiently good footing. At approximately 200l/min that is 6000l).

Orange Oil

Orange oil has been used to reduce dust on both indoor and outdoor arenas. Typically it is mixed with a detergent to allow it to be sprayed on with water.

Wax / surface additives

Waxed sands have been used in England and Europe for many years. They are hard to get and expensive in Australia. Furthermore, they have had a mixed reputation due to our higher operating temperatures.

Commercial Dust Suppressants

There are many of these on the market but they tend to work by causing the dust particles to clump. In a surface, workability must be maintained, so suppressants that remain fluid during their operating life are desirable. Factors that are important to consider are:
  • safety for you and your horse: you and your horse will be exposed to your dust suppressant - from experience I can say that it will get on your clothes, your saddle, your horses boots, your boots pretty much every where so it is vitally important that the chemical be safe
  • ecological impact - surface from an arena is pretty much guaranteed to escape from the arena on horses hooves and shoes. You should make sure that any chemical you use does not have a significant impact on the surroundings.
  • the interval between reapplication
  • reactivity with your surface - chemicals interact eg petrochemicals weaken some plastics, some chemicals are flammable in small quantities.
It is important to test that a dust suppressant does not cause any unexpected side effects - get a sample, make up a fair quantity of the mixture you intend to use on your surface and give it a few months sitting together just to make sure that nothing unexpected happens.

Planing for failure

When creating a surface it is important to have strategies for making it right if things don’t go to plan. In our case we put down the least amount of sand we could ie 50mm rather than 70mm because it is easy and cheap to add sand if the surface is too shallow - if the surface is too deep you can scrape some off, but that tends to waste the more expensive ingredients of your arena. We also chose to go with a single grade of sand as you can increase the rate of compaction by adding a different grade of sand if the surface is too loose. Finally, we ordered enough dust suppressant to allow for a second dose in two years time or to add more if the dust was not adequately reduced or the fibre absorbed the suppressant more than our tests indicated.

Having a plan meant that we knew what to do if there was a failure in the footing and meant that we did not waste the expensive parts of the surface.

We are pleased to report that so far so good the surface has performed as expected and we have not had to fiddle with the mixture.