I've been expecting a closed loop explosion, and per O Toole's Law, here is a splendid example of an ostensibly well intended, but woefully ignorant brother blowing himself up with a modified Lil Terp passive design. It's unclear whether he purchased it as is or assembled it himself, but he is clearly ignoring or ignorant of the most basic of the rules. http://www.aspentimes.com/news/16121402-113/vail-valley-man-injured-in-hash-oil-explosion For starters, he was extracting indoors, in a residence, which is not ever safe, because things can and do go wrong, go wrong, go wrong................ He is clearly in violation of the first, second, and third rules of CLS extraction, which are never extract indoors in a residence, never extract indoors in a residence, and never extract indoors in a residence. The forth rule is only extract indoors in a commercial setting, in an adequately protected and ventilated enclosure, as approved by the fire marshal. Regardless of where he was, he was demonstrably without adequate ventilation for the size leak that occurred. In industrial settings, the fire marshal would never issue a permit with out proper safety precautions like ventilation. The operator was wearing clothing that was not static free. Some of you have noted attacks on my credibility and sanity on line, by extractor manufacturers like Mr Extractor, when I called them on a demonstration where his demonstrator was burping a passive system indoors wearing a synthetic dress. Please note this incident appears to vindicate me and the NFPA guidelines, while flying in the face of Mr Extractors defensive argument that my claims were ludicrous . As you can see from the picture below , the Lil Terp design was modified with the addition of sight glass under the column, so that when flooded, it was locked between two valves. That subjects it to hydraulic forces as the butane warms and expands, which are measured in KSI as opposed to the 50 to 150 PSI they are rated for. That is why even 3X tanks designed to store butane, only allow an 80% fill, so that the system only sees vapor pressure. Though the operator said a valve leaked with a pop, valves typically leak by weeping or peeing past a seal, while a sight glass over pressure failure definitely makes a pop. Leaky seals don't suddenly release enough butane to blow up a house, but ruptured sight glasses do. In its current position, it isn't possible to see whether the glass is broken, but there is clearly no evidence of the three piece valve separating far enough for a release and a leaky valve seal is a jet, not a sudden release with a pop, not to mention it is visible and doesn't show evidence. The operator was also under the impression that his setup was legal in a residence, was safe to run indoors, and met CO regulations for a CLS. There is no reason that it shouldn't meet CO's regulations as the Lil Terp was originally designed without sight glass, but with it in the configuration below, there is no way it would meet the 3X requirements of ANSI and ASME. Hats off to this operator for attempting to extract safely, but a failing grade for pre-research. Part of that research was the safety and legal ramifications of extracting in a residence and locale, so in addition to burn treatment, he is facing a day in court on charges that can lock him up for a long time. Even if it is his house, I'll bet the insurance doesn't cover indoor extraction, and if it isn't paid for, the mortgage holder will no doubt have some thoughts on repairs. Close your eyes for a moment and imagine the changes it would bring to your life if suddenly you were badly burned, and were facing civil action for the damage, as well as high legal costs and prison time.......................................... GW 7-10-2015 Some of the comments suggest a lack of understanding of the laws for concentrate extraction in CO. I'm not a lawyer, so here is a link to what the CO Attorney General thinks on the subject, as well as a link and summary clip from CO's regulations on flammable solvent extraction: http://www.denverpost.com/news/ci_27231535/colorado-attorney-general-says-making-marijuana-oil-at https://www.colorado.gov/pacific/sites/default/files/Permanent%20Medical%20Marijuana%20Rules,%20Effective%20March%202,%202014_0.pdf D. Solvent-Based Medical Marijuana Concentrate. A Medical Marijuana-Infused Products Manufacturer that engages in the production of Solvent-Based Medical Marijuana Concentrate must: 1. Obtain a report from a Certified Industrial Hygienist or a Professional Engineer that certifies that the equipment, Licensed Premises and standard operating procedures comply with these rules and all applicable local and state building codes, fire codes, electrical codes and other laws. If a local jurisdiction has not adopted a local building code or fire code or if local regulations do not address a specific issue, then the Certified Industrial Hygienist or Professional Engineer shall certify compliance with the International Building Code of 2012 (http://www.iccsafe.org), the International Fire Code of 2012 (http://www.iccsafe.org) or the National Electric Code of 2014 (http://www.nfpa.org), as appropriate. Note that this rule does not include any later amendments or editions to each Code. The Division has maintained a copy of each code, which are available to the public; a. Flammable Solvent Determinations. If a Flammable Solvent is to be used in the processing of Medical Marijuana into a Medical Marijuana Concentrate, then the Certified Industrial Hygienist or Professional Engineer must: i. Establish a maximum amount of Flammable Solvents and other flammable materials that may be stored within that Licensed Premises in accordance with applicable laws, rules and regulations. ii. Determine what type of electrical equipment, which may include but need not be limited to outlets, lights, junction boxes, must be installed within the room in which Medical Marijuana Concentrate are to be produced or Flammable Solvents are to be stored in accordance with applicable laws, rules and regulations. iii. Determine whether a gas monitoring system must be installed within the room in which Medical Marijuana Concentrate are to be produced or Flammable Solvents are to be stored, and if required the system’s specifications, in accordance with applicable laws, rules and regulations. iv. Determine whether fire suppression system must be installed within the room in which Medical Marijuana Concentrate are to be produced or Flammable Solvents are to be stored, and if required the system’s specifications, in accordance with applicable laws, rules and regulations.