Yes, OSHA does hold employers accountable if they violate these regulations. A serious violation can result in a penalty of $12,675 per violation, a failure to abate $12,675 per day and a violation that is viewed as willful or repeated can result in a $126,749 penalty.
Unfortunately, OSHA is a fairly small agency. As a result, not every job site gets inspected. This can result in unchecked violations.