Writing a risk assessment can be done in a few ways. First, there is no "right" or "wrong" way to do a risk assessment. A risk assessment can be five pages or it can be 50 pages depending on how much information and data is included. An outline is always a good place to start and for the most part this has already been done in Chapter 5 of the NFPA 1851 standard. From here, fire departments can do everything on their own or they can look at risk assessments done by neighboring departments or large metro cities. Safety Components has a few thorough risk assessments done by some of the largest metro cities in the US for reference-email us if you want one.
The key is to do a risk assessment. By doing a risk assessment, the department may uncover previously unknown risks to its first responders...reshaping the type or performance of the PPE being purchased; the fire department may have a better chance at getting the PPE they want vs. low bid; the department and those involved in specifying PPE will be better covered if an accident occurs (less headaches with OSHA). For many reasons, performing a risk assessment is something every fire department should do.