Redlands Veterinary Clinic in Brisbane, owned by David Lovell, had been the subject of several complaints by horse owners following the outbreak which claimed the life of vet Ben Cunneen and also infected a nurse, who was later released from hospital.
The board said it had decided to take the unusual step of releasing its findings, given the public interest in the matter.
"Across all of the matters raised, the board was unable to determine that any prima facie case exists to support a finding of misconduct in a professional respect as defined in the Veterinary Surgeons Act (1936)," the board said in a statement.
"The board appreciates that standards must be continually improved but when considering the material before it took the view that 'one-off' or occasional hygiene deficiencies in a busy practice did not constitute professional misconduct."
It said that while it was not charged with investigating the Hendra virus infection situation at the clinic, it realised that the outbreak must be considered in upgrading standards and procedures in the future.
"Hendra virus is unique in Australia in representing a serious threat to horses and to humans. While Hendra virus remains a sporadic disease of horses, and would not normally be expected to be a likely occurrence in a veterinary clinic premise, its consequences demand stringent new standards."
The Veterinary Surgeons Board intends to work with the Australian Veterinary Association, through its special interest group Equine Veterinarians Australia and the relevant experts within the Department of Primary Industries to set new minimum standards and operating procedures.
"The board will also highlight to veterinary surgeons the importance of considering Hendra virus infection in their diagnostic process and in taking immediate steps to exclude this as a possible cause."
The board appointed an independent solicitor to carry out the investigation. The solicitor used two leading equine veterinarians, from Queensland and Western Australia, for expert comment on the facts gathered.
The board's officers also visited a range of Queensland equine practices and canvassed practices Australia-wide to ascertain what "normal" standards of hygiene and clinic practice existed.