This object reports the speed level of this fan as one of notSupported(1), off(2), low(3), medium(4), or high(5). Admins use it to see how hard a fan is working, which correlates with the thermal load on the component it cools and can indicate an environmental or airflow problem if unexpectedly high. For example, a fan reporting high(5) speed for an extended period might indicate the chassis is running hotter than normal and warrants investigation.