Helmet laws vary by country and even within different regions or states. Therefore, it's important to consider the specific jurisdiction in question. In many countries, it is mandatory for motorcyclists to wear helmets regardless of the speed they are traveling at. However, there are some jurisdictions where helmet requirements may differ based on factors such as speed limits or road types.
To provide a more accurate answer, please specify the country or region you are referring to, and I can provide you with the specific information regarding helmet laws in that area.