It depends a lot on the activity and the individual. I am almost 40, and I still won't use our bandsaw unsupervised. I don't think there is any age that I will trust myself with that because I am clumsy.
When my sister and I were growing up, we were given our independence in different areas at different ages: it was a matter of when we felt confident doing those things unsupervised and when we earned our parents' trust. As a general rule, I got to do responsibility-based tasks (like stay home alone, pick my own bedtime, and set my own homework schedule) at an earlier age than my sister, but she got to do physically risky tasks (like use knives, use the stove, and play high-risk sports) at an earlier age than me.
In all cases, it was a gradual process: they guided us, then they let us try while they watched, then they let us try while they were on hand if we called out for help, then they let us do it alone. Each step took as long as they (or we) felt was needed.
My parents are both highly anxious/cautious people, so I know it wasn't easy for them to give us these freedoms, but they understood intellectually that it was vital that we practice for adulthood well before we were suddenly on our own. They knew they only had a few short years to teach us how to survive independently of them.
It must have been a lot of work for them, but we were planned children (not accidents) and they put a lot of thought into how they wanted to raise us.
When my sister and I were growing up, we were given our independence in different areas at different ages: it was a matter of when we felt confident doing those things unsupervised and when we earned our parents' trust. As a general rule, I got to do responsibility-based tasks (like stay home alone, pick my own bedtime, and set my own homework schedule) at an earlier age than my sister, but she got to do physically risky tasks (like use knives, use the stove, and play high-risk sports) at an earlier age than me.
In all cases, it was a gradual process: they guided us, then they let us try while they watched, then they let us try while they were on hand if we called out for help, then they let us do it alone. Each step took as long as they (or we) felt was needed.
My parents are both highly anxious/cautious people, so I know it wasn't easy for them to give us these freedoms, but they understood intellectually that it was vital that we practice for adulthood well before we were suddenly on our own. They knew they only had a few short years to teach us how to survive independently of them.
It must have been a lot of work for them, but we were planned children (not accidents) and they put a lot of thought into how they wanted to raise us.