A WorkSafe investigation found that the ramp handle could dislodge from the winch shaft and no automatic brake system was in place for when the ramp was being lowered.
WorkSafe head of specialist interventions Simon Humphries said the worker had spent almost a month in hospital and was unable to work for nine months following the incident.
"The safety of workers can't be left to chance, and this worker has lifelong vision and hearing impairments as a result of a farmer's substandard equipment.
"Take the time to check your gear and if you have any concerns, engage a competent engineer to take a look and get things tidied up before your next truck arrives.''
WorkSafe has issued a technical bulletin for owners and users of mobile stock loading ramps available here.