What is the least common type of inspection conducted by OSHA?

The least common type of inspection conducted by OSHA is the imminent danger inspection. This type of inspection occurs when there is a legitimate and immediate threat to the health or safety of employees. OSHA prioritizes addressing situations where there is a serious risk of harm, which typically leads to prompt investigation and intervention. However, these inspections happen less frequently than the other types because imminent danger situations are rare compared to other more common scenarios, such as complaints from workers or general programmed inspections based on specific industry hazards.

In contrast, complaint inspections take place regularly when employees report unsafe conditions or practices, while programmed inspections are systematic evaluations of workplaces based on statistical data identifying high-risk industries or conditions. Fatality or accident inspections occur following serious incidents and, while significant, they are also less frequent than the more routine complaint and programmed inspections. Thus, imminent danger inspections are categorized as less common due to their very specific and urgent nature, making them the correct choice in this context.