Mom with a question (helicopters )

Good morning and thank you for the work you do My son worked on a handcrew for last three summers, and was offered a position on a helicopter crew. He is a seasonal worker. I know this is probably a silly thing to be asking all of you, please excuse my ignorance. How much more dangerous is working with the helicopter than being on the ground?I understand that flying is usually safe. I have searched on the web for more information and it still seems there are accidents sometimes. I don’t know the safety of flying commercially vs. flying for fire. I am trying not to worry and to understand the risks better. My son is a good firefighter but he knows nothing about helicopters. I want to learn more and hopefully set my mind at ease

Thank you for your time, stay safe