What are the major differences (in terms of how the response may differ and some of the challenges that first responders will face) between a traditional hazard such as the 2007 California Wildfires and the terrorist-related hazards associated with the Aum Shinrikyo Sarin Gas attack on the Tokyo Subway that occurred in March of 1995?
The major differences between these two come in the nature of the threats that first responders need to worry about and the degree of understanding that they are likely to have of the situation they are entering.
When first responders respond to a natural disaster such as a fire, an earthquake, or a storm, they are fairly certain of what they will be facing. They may not know the exact details, such as exactly how big the fire is, but they will know the general types of hazards that are typically present in such situations. These are relatively generic situations and there are standard procedures for how to respond. By contrast, terrorist attacks can be much less generic. There had not, for example, been many gas attacks on subway systems in which first responders could have built up standard procedures.
Secondly, when first responders respond to a natural disaster, they do not need to worry about who might have caused the disaster or what those people might be planning to do next. When there is a wildfire, there is no need to worry that somehow the fire is lying in wait to harm you in some unexpected way. In a terrorist attack, such worries do exist. It is not clear as to what has happened, who the perpetrators are, and what they might be planning to try to do to the first responders.
These are the most important differences between these types of hazards.