At no time after he commenced employment was the victim offered screening or vaccination - the best method to prevent the disease.
The court was told that in part of his work the victim was exposed to the hazards of fresh and dried blood and body fluids, which could contain active Hepatitis B.
In March 2015 he was hospitalised and diagnosed with acute Hepatitis B infection.
It was accepted that it was not possible to establish that he actually contracted the disease while at work, but Rentokill was still found to be culpable.
The company had subsequently reviewed its processes, updated its health surveillance procedure and established a register of all employees working in the Initial Hygiene division to track Hepatitis B results and immunisation.
"While on the one hand the consequences of the failure to take the identified practicable steps in this case could be, and were, very serious, the failures occurred against the defendant having policies that were ahead of the industry standard," the decision said.
Imposing a sentence, Judge Lance Rowe took into account the company's previous good safety record. However, the company had displayed no remorse and initially pleaded not guilty, only changing its plea two weeks before a scheduled trial.
"[The victim] has suffered considerable emotional harm as a result of the defendant's failure to offer him immunity testing or a vaccine. He is entitled, in my view, to feel aggrieved that he has contracted Hepatitis B in the face of these failures on the part of the defendant."
Judge Rowe imposed a fine of $29,250 and ordered the company to pay the victim reparation of $10,000 for emotional harm and $4,998.64 for lost earnings.