Model codes and standards include explicit design direction for only a small number of hazard types. Given the very large number of pages addressing hazard protection in the IFC and NFPA standards, that may seem to be surprising, but codes and standards in general usually provide detailed protection guidelines for broad classes of hazard types and severities, whereas actual hazards are very specific to the individual circumstances. Codes and standards must be interpreted from the general to the specific.
Innovation is the key to marketplace leadership, so it is not surprising that unique hazards are associated with innovative process designs.
Circumstances for which explicit guidelines are not available are addressed with Performance Based Design (PBD) procedures. PBD is also utilized to advance design concepts that are proposed in substitution of a design which is included explicitly in the Code. These new designs are advanced as Alternate Materials, Design and Methods proposals, as allowed per the IFC and IBC.
Car parking stacker systems - explicit design guidance is provided in NFPA 13 for two-high car stackers, but there is no guidance for three-high and higher.
Inert compressed gas use - an asphyxiation hazard exists if the inert gas can be released in a confined space. Calculations can indicate the resulting oxygen level for personnel safety.
Cryogenics - Cryogenic flammable liquids (LH2, LNG, LPG) present hazards related to ultra-cold temperatures and highly flammable materials. All cryogenic systems, including inert materials, can be subject to process interruption if not designed with a specific reliability target.
Special materials - Materials which cannot be protected as ordinary combustible materials are include substances that are pyrophoric, water reactive, and toxic. Adequate protection of hazards involving these materials often require combinations of water-based systems, special fire protection such as gaseous or chemical, emergency ventilation, passive protection such as fire barriers, and damage limiting construction.
Guidelines for fire protection of "in-use' ignitable liquids hazards are included in NFPA 30 Flammable and Combustible Liquids Code for only a few specific processes. There is no protection guidance for the vast majority of processes. This circumstance surprises many. If it's not in NFPA 30, where is it?
The answer is that there are no explicit guidelines because the circumstances of the hazard depend on the nature of the anticipated failure. For example, if a leaking pipe results in an ignitable liquid spill fire, is the spill area large or small? Did ignition occur early in the spill of was it delayed? These decisions can result in vastly different scenarios and associated ultimate hazard consequence. A Process Hazard Analysis (PHA) is often required.
Distilleries - The scope of NFPA 30 does not adequately address the special hazards including flammable liquids pool fires, spray fires, and flammable vapor explosions which do are inherent in distilled spirits production.
Distilled spirits storage in wood barrels is not included in the scope of NFPA 30. A Performance Based Design concept is required, with careful attention to the latest research and testing. Industry fire protection design guidelines are often inadequate.
Hydrogen gas systems are becoming more common, such as in fuel cells, lead-acid battery Energy Storage Systems (ESS), hydrogen powered vehicles, and fork trucks in storage areas. The hazards related to compressed hydrogen gas or liquified hydrogen are unique. The molecule size makes GH2 prone to leaks. Ignition on gas release is likely and hydrogen flames are not visible. The flammability range is wide, and detonation is possible.
A Process Hazards Analysis is commonly required to determine fire protection and associated safety systems, such as process reliability, ventilation and fire detection.
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