Final answer:
The term 'low fence' in workers' compensation cases is the hearing threshold level at which impairment is considered compensable and varies by state.
Step-by-step explanation:
In workers' compensation cases, the term low fence refers to the hearing threshold level at which impairment is considered compensable or where hearing impairment begins.
This level varies by state, as each state may have its own regulations and criteria for determining when a worker is eligible for compensation due to hearing loss. The low fence is used to establish the severity of hearing loss that must be met before workers' compensation benefits can be granted.