Virkon is the trade name. There are a few different varieties. Virkon S is the one you need. You can get sachets, tablets or tubs of it. I got a tub a while ago as we had a stray kitten with ringworm in isolation in a house full of furries (and us). I also used it in a microbiology lab to clean the worktops. The full usage info is here:
http://www.dolittlefarm.com.au/docs/VirkonBrochure.pdf
Basically, you need a 1:100 dilution for most applications.
A 50g sachet makes 5 litres of disinfectant, or 2 x 5g tablets in a litre.
Tubs come with a measuring scoop.
Disinfection is effective if concentration and contact time are followed. Contact time isn't very clear, but 10 mins is quoted for parvovirus. So leave the floor wet (damp) for 10 mins, or soak items for at least 10 mins at the recommended dilution. FHB (rabbit vet) said RHD was similar to the cat Calicivirus which is listed on the info sheet. Air drying is always best to maximise the disinfectant effectiveness - uv / sunshine also helps the effect. If it leaves a slightly gritty film on the floor, it can be wiped off after, although the formulation is much better than I remember when we used it in the lab.
You can soak bowls, toys, etc in it in a bucket. It can be used in the washing machine for bedding, clothes, etc in with the washing powder.
If you make up a spray bottle, it will keep for a week - which is pretty good for a disinfectant, and handy for random daily cleaning. It does lose its colour and degrade to chlorine compounds, so starts to smell of bleach if you keep it too long.
It's quite nice stuff considering how effective it is - a pink solution with a slight lemon scent and it doesn't wreck your hands - but gloves should really be worn by the user.