it is 4 years since the manufacture date, which is indicated under the cap, there is round shape and digits are placed by the inner edge, arrow shows on to the number indicating month, the digits in the middle (usually by the each side of tge arrow) are indicating year.
There is no legal requirement for hard hat expiry date as it varies based on the condition 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, hard hats should be replaced after two years of use. In addition, some manufacturers even recommend replacing the suspension in your hard hat every 12 months.
How to know the age of your hard hat
Different manufacturers states the lifespan of their hard hat.
However, to trace the age of your hard hat, you must know its manufacturing date.
The manufacturing date for an hard hat is stamped on the hard hat – It is known as DATE STAMP