Bio security is a funny one, I suppose it depends on how many animals you are dealing with and type. Pig farmers are generally ahead of the curve on this (because they have to be) compared to cattle or sheep etc and obviously if you are fattening the odd weaner for the freezer you might not feel the need to embrace all the regulation and best practices of the industry.
For what it is worth the bepx and red tractor schemes (I use those two because I know them) are similar
Bpex:
http://www.bmpa.uk.com/_Attachments/Resources/4831_S4.pdfRed tractor:
http://assurance.redtractor.org.uk/resources/000/799/072/RT_%28ABMABP%29Transport_Standards_v2_4_June_2011_%28change_to_2.2.1_13.01.14%29.pdfI use a normal car wash detergent, then rinse, then FAM 30, then rinse again on my trailer plus arks, troughs etc between batches of pigs.
It is important to remember that disinfectant is not a detergent and should only be used on already cleaned surfaces. If you are transporting pigs it is particularly important to remember this as their feces (as in humans) contains fats that are difficult to break down.
Steam cleaning is exactly that, a 'cleaning' process. It is not a recognised form of disinfectant and as posted above you should only use one of the approved chemicals noting the dilution and contact time required.