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What you do is important. I was again reminded of the critical nature of fire protection planning, prevention, and response when reading Nat Brandt's 2003 book "Chicago Death Trap: The Iroquois Theatre Fire of 1903." It was and still is the largest loss of life in U.S. History due solely to a fire. What Happened Touted proudly as "Absolutely Fireproof," the Iroquois Theatre opened as destination of grand opulence and ornate design. On December 30th, just over a month after opening, a calcium arclight on stage shorted, causing roughly 6-inches of wire to overheat and ignite. A nearby drop curtain quickly caught fire, spreading the flames up through the vast amounts of scenery material above the stage. Attempts to extinguish the fire using chemical canisters were ineffective, and an asbestos fire curtain failed to lower into place due to lighting supports that obstructed the curtain's path. In an attempt to thwart the electrical nature of the early fire, stage lights were shut off, but broken fuses then left the auditorium and lobby without any light. Covered, confusing, unmarked exits and some with locked doors made egress in the auditorium and through the lobby impossible for many, resulting in a rushed panic, trampling, and further blocking of exits. Within five minutes of ignition nearly the entire set above the stage was inflamed. A large iron door to the rear of the stage was opened by stagehands escaping the fire, only giving fresh air to the fire. Skylights above the stage, which had intended to open as smoke and heat vents, were inoperable due to clamps not removed after installation. Exhaust above the rear of the auditorium pulled smoke up and into the auditorium. Within a half hour the fire was completely extinguished, with a death toll due to trampling and smoke inhalation that still is unfathomable.  Chicago Death Trap: Iroquois Theatre Fire of 1903 by Nat Brandt Contributors to Loss of Life Early attribution to the 602 deaths from the fire was incorrectly blamed upon panic, in part a chauvinist attitude that the crowd full of women and children acted inappropriately. Later study and report identified numerous major contributors to the major loss of life as
It was mentioned that given our modern understanding for fire hazard and egress, it was surprising that most of the 1700 people in attendance that day were even able to escape. Aftermath Following the fire, tougher inspections began throughout the country and in theaters worldwide. All theatres in Chicago were closed until inspected for safety could be completed. After years of legal disputes, ultimately no one was found legally responsible for the tragedy. Reform brought clearer language to ordinances with better-enforcing authority, but even those were slow to change. Major changes as a result of the fire included:
Thoughts on The Book by Nat Brandt This powerful volume was well comprised and focus almost entirely on the fire and its aftermath with long-standing implications. I would recommend it for those who want to understand the awful implications of very poorly planned construction paired with lack of enforcement. As a father, this was a very difficult read. There were stories of efforts to escape the fire by so many (successful and unsuccessful), but particularly awful was the large numbers of women and children who couldn't escape. I cannot imagine the incredible toll this event had for victim's families. It is truly sad that such a long list of fallacies were overlooked to create such a horrendous tragedy. Do we have the problem solved today? Do all areas of the world have resources to prevent these kinds of tragedies? I wish the answer was yes. What I can say is that I feel fortunate to live in a time and location where there is more recognition and enforcement for life safety, and to be in a position to help contribute towards a safer built environment. Protecting life is important. What you contribute as part of the fire protection industry is important. Interested in more? Subscribe to these articles. You're already familiar with the inspector's test as a required component of a sprinkler system, but today we're diving into the true purpose and details behind this important aspect of a sprinkler system. The purpose of the Inspector's Test can include: providing the ability to (1) test the sprinkler system's alarm/waterflow device, (2) test the opening of a dry-pipe or pre-action valve (for dry-pipe or pre-action systems systems, of course), (3) test the trip time from when the valve is opened to the arrival of water, where necessary, and (4) can aid in venting trapped air. The inspector's test can be coupled as an air vent for a wet system or an auxiliary drain, although we'll explore those components in more detail separately.  Figure 1: Example arrangement of an inspector's test and drain which is remote from the riser Discharge: Used to discharge water during the test or draining of the system. Discharge must:
Drum Drip: Provided for dry or pre-action systems to collect condensate within the system for purging. At a minimum they must be:
Orifice: The orifice (within a sight/site glass) simulates the flow of a single sprinkler in order to ensure that the sprinkler waterflow alarm will activate upon the flow of a single sprinkler. The orifice must:
 Figure 2: Inspector's Test Connection to dry-pipe system when not used as an auxiliary drain Sight/Site Glass: typically provided where water discharge is not visible from the control valve (NFPA 13 2002 A.8.16.4.2, 2007-13 A.8.17.4.2, 2016 A.8.17.4.1). As a side note, I don't understand why Drive Thrus and Site Glasses are spelled the way they are, but I don't try to fight the system. Just know that common language often refers to these as 'site' glasses despite not actually referring to a large area of land. Supply: The supply simply connects the most remote branchline from the riser to the inspector's test (for a remote inspector's test). It must:
Tags must:
Valves:
Wall Penetrations:
 Figure 3: Inspector's Test and Drain Located at a Floor Control Assembly When & Where Required: inspector's tests are required on each wet, dry, or pre-action sprinkler system:
We hope this was helpful. Don't get these? Expand your expertise by receiving these straight to your inbox, for free: I’ve rethought my career only a few times in my life. None of which were very serious, often more or less originating as daydreams of becoming a full time artist and living on a beach. Not so a few years into the profession when I ran into a major design issue on a premiere project. The job was a large commercial headquarters split by a four-story atrium that was coming together as an architectural achievement in itself. Nothing outlandish or world-renowned, but in my limited experience it was the biggest and best project I had worked on to date. Design phases came and went with big deadlines any consultant has surely experienced. Our scope at the time was limited to design-build (or performance specifications) fire alarm and sprinkler system plans and specifications. We coordinated standpipes, flow switches for smoke control zones, data center clean agent systems, graphic annunciators, and other features not commonplace in most office buildings.  Atrium connecting two office towers with glass stairwells It wasn’t until a day before my wife and I were to leave on a week-long Christmas vacation that I received word that a large change order coming based on a difference between our expectations for sprinkler protection and the contractor’s bid for both of the atrium’s four-story stairwells.
Today we're diving into the basic components of a fire sprinkler:  Orifice (Opening)
The orifice varies in size, but has a major impact on the sprinkler's k-factor which ultimately governs the sprinkler's relationship between flow and pressure. Opening sizes vary fairly dramatically but in general are not a major driver for sprinkler selection. Threading The nominal threading sizes range in quarter-inch increments from 1/2-inch to 1-1/4-inch (although some dry pendent shafts do have 1-1/2-inch threads). Thread size of sprinklers can be gathered in the field simply by measuring the diameter of the thread shaft. Sprinklers with a k-factor greater than 5.6 are no longer allowed to have thread sizes of 1/2-inch (NFPA 13 2002-2016 Section 8.3.5). Plug The plug retains the water (and pressure) within the sprinkler and pipe network. Breakage of the liquid-filled glass bulb results in the release of the plug, and thereafter the water. Sealed Liquid-Filled Glass Bulb Modern commercial sprinklers mostly rely on the colored glass bulb as the thermal sensor in the fire sprinkler, but other types are still frequent as well. Color of the liquid within the bulb indicate the listed activation temperature of the sprinkler (and can be found in NFPA 13 2002-2016 Table 6.2.5.1). Frame & Deflector The frame can have many finishes, of which some of the more common are listed above. The deflector offers the basic premise of the fire sprinkler - which is to distribute water in a specific pattern to best combat a fire hazard within an enclosure. Deflectors vary depending upon the style of the sprinkler and work to achieve different objectives. A residential pendent, for example, throws water with greater emphasis to the walls and ceiling where hazards are more commonly present in residential occupancies. Don't receive these articles? Sign up today and get these free weekly posts straight to your inbox. |
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+ Unsubscribe anytime AUTHORJoe Meyer, PE, is a Fire Protection Engineer out of St. Louis, Missouri who writes & develops resources for Fire Protection Professionals. See bio here: About FILTERS
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