I received the following questions about design of fire and gas detection and suppression systems in process industry applications from a client. After answering I figured that I would share the information, as these questions are quite frequently asked.

(1)    Is the NFPA 72 a fire standard/guideline applicable to “only buildings’ ? Does any certifying body check for compliance with NFPA-72 in process areas (or for gas detection)?

The NFPA standard, or “The National Fire Alarm Code” is a general purpose standard that is primarily written for fire alarm equipment in occupied buildings.  It is really up to “the authority having jurisdiction” whether or not it is applicable to a certain facility.  In the US, that “authority” is the local Fire Marshall.  The Fire Marshall is a person that is associated with Local (city-level, possibly state-level) Fire First Responders.  Fire Marshalls typically randomly audit facilities in their jurisdiction to determine whether or not they are in compliance with standards that have been incorporated by reference by local law – and the National Fire Alarm Code is typically one of those – for instance, a fire marshal has recently stopped by the Kenexis building and checked our fire extinguishers.  In my experience, I have never seen a Fire Marshall apply the requirements of NFPA 72 to anything other than an occupied building.  Open process areas do not fall into the category of “occupied buildings” and I am not aware of any instance where anyone was cited by any authority for not following NPFA 72 in open process areas that are out-doors.  On the other hand, I am aware of Fire Marshalls that check for NFPA compliance in process areas that are located inside a building.  Even in these cases, only the fire detection system is in the scope of audit, and not gas detection which is not covered by the NPFA 72 standard.

The segregation between what is indoors and what is outdoors is so important, that it is not uncommon for an offshore platform or FPSO to have two separate FGS systems, one for the occupied buildings that is NFPA 72 compliant and a separate one for the open process areas that is NOT NPFA 72 compliant.

(2)     Does a fire alarm HMI panel need to comply with NFPA-72 and certified be with FM or UL listed?

If the specific alarms in question indicate the presence of a fire in an occupied building, then yes.  These alarms would need to adhere to the requirements of the “Notification Appliances” sections of the NFPA 72 standard.  Alarms that do not fit the description of indicating the presence of a fire in an occupied building do not.

(3)   Which NFPA standards set requirements for how deluge is triggered? (i.e., automatic from the  local fire alarm panel? Independent deluge fire alarm panel? By manual activation? By mechanical breakage (sprinkler or fusible plug) activation?)

NFPA 16 – Standard on Deluge Foam-Water Sprinkler and Foam-Water Spray Systems provides information regarding the implementation of these systems once it has been determined that they are required to be installed, but does not provide much detail on risk analysis for the determination of their requirement.  NFPA standards are also available that set requirements for the use of sprinkler systems in occupied buildings, most of these being automatically triggered by frangible bulbs activated by high temperatures.  For process plants, especially open area process plants, there are no prescriptive requirements from NFPA with regards to when they are required and whether they should be manually activated, or automatically activated.  These decisions are left up to the individual operating companies and are either prescriptively set in a company’s FGS Philosophy documents, or determined on a case-by-case basis using risk analysis techniques.