Generally speaking, the shelf life of the national standard ABS V-shaped safety helmet is about 30 months. But this is not absolute, its actual service life is also affected by factors such as frequency of use and usage environment. If the safety helmet is frequently used and operated in harsh environments such as high temperature, high humidity, strong acidity and alkalinity, its aging rate will accelerate, and it may need to be replaced in advance. Even within the shelf life, if the safety helmet has been subjected to significant impact, even if there is no obvious damage to the appearance, it should be immediately stopped from use and replaced, as the internal structure may have been damaged and reliable protection can no longer be provided.