My experience is no.
When I was a paid pro ski patroller I could not write off my equipment, cloths, travel......We are talking expensive requirements. Now my accountant explained I could get travel expenses paid for the day if I met with some one at the mountain to discuss tree work, like discuss a job, sign a contract or receive payment.
When I was a volunteer patroller I could, so long as I "only" volunteered with this equipment.
When I worked for a company and had to wear steel toes and jeans, I could not write them off.
When I work for myself now, obviously I can. The accountant brought up the fact that while yes I can write off my chainsaws 100%, how did I cut fire wood and clear rec trails at my house???? I replied, In the course of testing and training my equipment for work. Like putting a gym and hot tub in your shop because you are a climber/athlete. It would be a "flag" if the gym was in your house, I do not even write my office in my house off, I clearly do not use it 100% for tree work. When I have a shop and the office is in there it will be written off.
Some situations are cut and dry some are using the right words to benefit your cause. Crafty accounting.
Sounds like you should get a dba and start a business.