Editing Boiler (section)

==Safety==
{{see also|Boiler explosion}}
To define and secure boilers safely, some professional specialized organizations such as the [[American Society of Mechanical Engineers]] (ASME) develop standards and regulation codes. For instance, the ASME [[Boiler and Pressure Vessel Code]] is a standard providing a wide range of rules and directives to ensure compliance of the boilers and other [[pressure vessels]] with safety, security and design standards.<ref>{{cite web| url=http://www.tuv.com/en/corporate/business_customers/plants_machinery_1/pressure_equipment_2/asme_1/asme.html| title=Boiler and Pressure Vessel Inspection According to ASME}}</ref>

Historically, boilers were a source of many serious injuries and property destruction due to poorly understood engineering principles. Thin and brittle metal shells can rupture, while poorly welded or riveted seams could open up, leading to a violent eruption of the pressurized steam.  When water is converted to steam it expands to over 1,000 times its original volume and travels down steam pipes at over {{convert|100|kph|mph}}. Because of this, steam is an efficient method of moving energy and heat around a site from a central boiler house to where it is needed, but without the right boiler feedwater treatment, a steam-raising plant will suffer from scale formation and corrosion. At best, this increases energy costs and can lead to poor quality steam, reduced efficiency, shorter plant life and unreliable operation. At worst, it can lead to catastrophic failure and loss of life. Collapsed or dislodged boiler tubes can also spray scalding-hot steam and smoke out of the air intake and firing chute, injuring the firemen who load the coal into the fire chamber. Extremely large boilers providing hundreds of horsepower to operate factories can potentially demolish entire buildings.<ref>{{cite book| title=The Locomotive| author=Hartford Steam Boiler Inspection and Insurance Company| publisher=Hartford Steam Boiler Inspection and Insurance Co.| year=1911| via=Google Books| url=https://books.google.com/books?id=-LYSAAAAYAAJ&pg=PA1}} An article on a massive Pabst Brewing Company boiler explosion in 1909 that destroyed a building, and blew parts onto the roof of nearby buildings. This document also contains a list of day-by-day boiler accidents and accident summaries by year, and discussions of boiler damage claims.</ref>

A boiler that has a loss of feed water and is permitted to boil dry can be extremely dangerous. If feed water is then sent into the empty boiler, the small cascade of incoming water instantly boils on contact with the superheated metal shell and leads to a violent explosion that cannot be controlled even by safety steam valves. Draining of the boiler can also happen if a leak occurs in the steam supply lines that is larger than the make-up water supply could replace. The ''Hartford Loop'' was invented in 1919 by the [[Hartford Steam Boiler Inspection and Insurance Company]] as a method to help prevent this condition from occurring, and thereby reduce their insurance claims.<ref>{{cite web| first=Dan| last=Holohan| url=http://www.massengineers.com/Documents/Hartford%20Loop.htm| title=What you should know about Hartford Loops}}</ref><ref>{{cite web| url=http://inspectapedia.com/heat/Hartford_Loop.php| title=The Hartford Loop on Steam Boilers}}</ref>