Hold a tailgate session before going out on the trail.
Remember that all crew members have the obligation to say "NO" and walk away from any situation they determine to be an unacceptable risk and an obligation to notify others if it is safety hazard to the general public.
Outdoor Activity Safety Guidelines First Aid
Someone on the trip should have Wilderness First Aid
If more than one first aider is on trip, appoint one as the chief based on training and experience.
Talk to your party members before going out to find out if they have any medical issues, e.g. allergic to bee stings and have appropriate medications with them, e.g. EpiPen.
Sharp tools are safe tools
Griphoists need regular lubrication
Check cables and slings for wear every time you use them
Spray paint handles (or other parts) bright yellow or orange so they are easily found if placed off trail
Inventory tools at the end of every trip
Be safe, have fun, do work - in that order
Stop work for the day if it is too hot or too rainy
Provide refreshments such as lemonade and brownies
Rotate workers on the strenous activities
Have a someone who manages the people part while the other leader focuses on the technical parts of the job. You can't do good work if no one shows up.