According to the ERA, it was clear Mr Gemmell "saw the matter as a debate about the merits of having a portaloo on site" rather than him disobeying an instruction his manager gave him.
Mr Gemmell was asked over four days to remove the item from his worksite, but failed to do so.
According to the authority, Mr Gemmell did not refuse to remove the portaloo, but was "dragging (his) heels".
On February 18, Human Resources manager Jeremy Harker attempted to give him a letter that indicated his suspension, but Mr Gemmell refused to accept it.
The authority said Mr Gemmell "refused to accept the letter because he was annoyed that he was being given it before being asked for his version of events".
Two days later, he admitted he delayed following instructions.
The supervisor also raised health and safety issues about removing the portaloo.
But the authority said he did not previously raise these concerns.
On February 23, Mr Gemmell was dismissed.
The authority found QRS's decision to be "fair and reasonable employer could come to in all the circumstances at the time".
It also found Mr Gemmell would have been in a better position to respond if he hadn't refused the letter of suspension.
"It [QRS] could not force him to take, and read, the contents of the envelope".
However QRS admitted their suspension of Mr Gemmell was unlawful as there was no consultation before it was imposed and no opportunity for his views to be heard.
The authority ruled QRS breached their human resources manual requirement that "employees be given the opportunity to comment on their proposed suspension, and to have their views considered" before a suspension was ordered.
Mr Gemmell was awarded $4000 in compensation for "the grievance he suffered" from this.
