After you have determined the size of fuel tank you need for a diesel fire pump, what are the general requirements for installation? Assuming that you are under under the International Building/Fire Codes, you would go through the following chain of code references: IFC (2021 edition) 5701.2 Nonapplicability. This chapter shall not apply to liquids as otherwise provided in other laws or regulations or chapters of this code, including: ... (4) Storage and use of fuel oil in tanks and containers connected to oil-burning equipment. Such storage and use shall be in accordance with Section 605. For abandonment of fuel oil tanks, this chapter applies.. IFC (2021 edition) 605.1 General. The design, construction, installation, operation, alteration, repair and maintenance of nonportable gas-fired appliances and systems shall comply with the provisions of this section and the International Fuel Gas Code. The design, construction, installation, operation, alter...

Make sure you are in compliance with FM Global's requirements for cooling loops on diesel engines. FM Global Approval Standard 1333 was updated in 30 Nov 2013, but compliance was not required until 1 April 2015.
Clarke Fire has an excellent write-up on their web page that you can find here. But, we wanted to summarize the key requirements.
- FM Approval - Cooling loops are now required to be approved and therefore they will have the FM logo on a nameplate.
- Low Raw Water Flow Alarm - This switch is set to activate at 75% of the required flow rate.
- High Raw Water Temperature Alarm - This switch is set at 105F (40C).