This afternoon the folks at DHS Infrastructure Security Compliance Division (ISCD) updated the CFATS Knowledge Center, revising the response to one of the large number of frequently asked questions (FAQ). According to the ‘Latest News Entry’ for CFATS Knowledge Center:
The answer to FAQ 184, “What is a thermal radiation zone?” was updated to provide greater clarity and include links to additional resources.
Entering ‘184’ (don’t waste your time with ‘FAQ 184’, ‘FAQ #184’ or ‘FAQ Number 184’; they won’t get you there) into the search block on the CFATS Knowledge Center page and then clicking through the question “What is a thermal radiation zone?”, you get taken to the FAQ 184 page (Sorry, I can’t give you a link, there are no permanent links to FAQ responses).
Once there you get informed that the term is used in “Section 6.0 of the Department of Homeland Security, CSAT Top-Screen Survey Application User Guide” and are provided with a printed copy of a link (not actually a real link, just a cut and paste copy of a link. I don’t understand why, but that is the way they do it in all of the FAQ responses). Actually, sections 6.2 and 6.3 (pgs 31 and 32) refer to questions about thermal radiation zones for liquefied natural gas facilities.
The new response explains:
“Thermal radiation refers to the radiation emanating from a fire burning above a liquefied natural gas (LNG) spill. Thermal radiation from on-site fires fed by an evaporating pool of spilled LNG can cause first, second and third degree burns. The CSAT Top-Screen Survey Application User Guide references U.S. Department of Transportation regulations 49 C.F.R. § 193.2057 (2010) and 49 C.F.R. § 193.2059 (2004) [Links added], which provide modeling and parameters information for a thermal radiation zone,”
It also goes on to provide a copy of link to Part 193 of 49 CFR in the Electronic Code of Federal Regulations. In the quote above I have added actual links to the sections referenced. Again I am not sure why ISCD doesn’t go that one extra step to make it just a little bit easier for most folks that are not used to navigating the CFR.
This is an improvement of sorts over the earlier answer that was put into the FAQ Response list back in August of 2007. That earlier answer was more technically correct, but decidedly unhelpful to anyone searching for information. It simple stated that:
“Thermal radiation occurs from a fire burning above a liquid spill on the site. Thermal radiation from on-site LNG fires fed by an evaporating pool of spilled LNG can cause first, second or third degree burns to the skin of humans exposed to the radiation, depending upon the intensity of the radiation. For a given fire, this intensity decreases with distance from the fire. Under FERC rules, the allowable exposure is 5 kilowatts per square meter, an amount that produces second degree burns after only thirty seconds exposure. FERC allows thermal radiation beyond the site boundary as long as its level is below 5 kilowatts per square meter. This is the thermal radiation zone.”
Neither of these answers would be particularly helpful in providing guidance on how to answer the one Top Screen Questions related to the ‘thermal radiation zone’. That question is:
“Provide the distance (in feet) of the 5kW/m2 thermal radiation zone using the 49 CFR Part 193 site requirements (§193.2057).”
To find out how to do this calculation you have to go to §193.2057(a) to find out that you have to use a computer model from the Gas Technology Institute; GTI–04/0032 LNGFIRE3. This computer model is available from the Gas Technology Institute for the paltry sum of $500. Now I suspect that most LNG storage facilities already have someone on staff that has access to LNGFIRES3. That means that it isn’t quite the financial burden that it would seem at first.
Still, it would have been helpful to have the information about the LONGFIRE3 software available in this FAQ instead of making people dig through the CFR entry and then go searching for the program. Of course it would be even more helpful if there had been a link provided to a no fee copy of the software, even an abbreviated version of the software that would just allow the calculation of the 5kW/m2 thermal radiation zone.