One cannot guarantee 100% safety in any industry, but you can make it as safe as reasonably practical. That is the job of safety managers and the like.
A decade or two ago, the chairman of a well-known airline asked the safety manager to guarantee that they would not have any accidents. His reply cannot be repeated here, however it showed that many board members (and other senior managers) of aviation companies have little or no knowledge of safety and how it is managed. They don't want any holes in the ground but their willingness to cover safety in their budget/s is at best sometimes not appropriate.