عمر مفید یک کلاه ایمنی hard hat
[align=left]OSHA does not specify the service life of a hard hat, and there is no standard expiration time frame for hard hats.Hard hat life span may vary depending on the conditions of each work site. As a general guideline, most hard hat manufacturers recommend replacing hard hats every five years regardless of outside appearance.If you work under extreme conditions, such as exposure to high temperatures, chemicals, or sunlight, h
