How many incident levels are there?

Could you please clarify for me how many different levels of incidents are typically recognized or categorized within the context of cryptocurrency and finance? Understanding the various tiers or severities of potential issues can be crucial for risk management and incident response strategies. Are there standardized guidelines or frameworks that the industry adheres to when it comes to classifying incidents? Additionally, how does the severity of an incident typically impact the steps taken to address and mitigate its effects?