Final answer:
Adjust the headband of your hard hat so that there is appropriate clearance between your head and the shell for safety, with newer guidance suggesting up to 8 diameters side-to-side and 15 diameters deep.
Step-by-step explanation:
When adjusting the headband of your hard hat, it is crucial to ensure a proper fit for both safety and comfort. The webbing should be adjusted so that there is a clearance between your head and the shell of the hard hat. This space acts as a shock absorber during an impact. While an older rule of thumb recommended a clearance of 5 diameters side-to-side and 7-8 diameters deep, more recent guidance suggests that a clearance of as much as 8 diameters side-to-side and 15 diameters deep may be more effective for safety. It's important to consult the manufacturer's instructions for the specific hard hat you are using, as recommendations can vary based on design and materials. However, in general, ensuring appropriate clearance between the webbing and the shell of the hard hat is key to maximizing the protective benefits of the headgear.