经过Gregory Havel
数百年，闪电罢工对建筑物和其他建筑物造成了严重的破坏，并杀死了被袭击的建筑物的居民。今天，保护结构免受雷击的影响比1752年在实验时更为精确，本杰明·富兰克林（Benjamin Franklin）对雷电保护的最初发明。
原本的闪电protection system of that era included a number of metal rods attached to the walls and roof of a building. These rods were connected by copper wire, which was connected to metal rods driven 10 feet into the ground. When lightning struck, it usually struck a rod and its energy was transferred to the ground by the lightning rods, cables, and ground rods. The alternative to this is that energy being transferred to high-impedance or non-conductive building materials.
Lightning它对建筑物的影响已被研究了250多年。国家消防协会（NFPA）标准780中定义的今天的闪电保护系统，安装雷击系统的标准，2011版：
NFPA 780：3.3.22*Lightning Protection System.“罢工终止设备，导体（可能包括导电结构成员），接地电极，互连导体，电涌保护装置以及完成系统所需的其他连接器和配件的完整系统。”
保护生命和财产免受的基本原则闪电是提供一条路径，电能可以进入或离开地球而不会损害结构。金属棒，电缆和接地电极提供的低阻抗路径对于此目的是理想的选择，只要路径从接地电极连续到建筑物的端子。
建筑物的部分最有可能被闪电are the edges, corners, ridges, and dormers; The other parts most likely to be struck are those that project above the surrounding parts of the building, like chimneys, spires, railings, skylights, and dormers.
一个闪电罢工始于云和地面的电荷的差异。通常，云具有负电荷，地面是正电荷，尽管偶尔会逆转。云中的负电荷形成引导通道和向地球发展的低电流排放。当向下领导者的下端接近地面或扎根物体时，向上的领导者从突出的角度启动并延伸到向下的领导者。当向下的领导人与向下的领导者联系时，高电流的返回式中风开始。
主要原则闪电保护是为了确保与向下领导者建立联系的领导者很可能起源于空气码头，而不是由于结构的一部分而不会受到将通过它流过的电能损坏的。有关雷击机制和雷击系统功能的详细说明，请参见NFPA 780-2011，附件B。
（1）
高架空气码头（照片1）提供所需的保护，只要它们是系统地定位的，并且按照NFPA 780的要求。这些空中码头为散布在其下方的区域提供保护，称为“保护区”。
这些空气端子设计为安装在不同类型的表面（照片1和2），并使用连接器将不同类型的材料安装到对空气端子或附着的材料上不会具有腐蚀性的连接器。
Note that most air terminals are short and taper to a point. In the dark, smoke, rain, or fog, these can pose a trip and impalement hazard to firefighters on the roof.
空气终端还用于保护屋顶上方的投影和屋顶上的金属物体，例如照片1中的金属烟囱。空气终端连接到主导体电缆（照片1和2），该电缆连接到两个或更多。向下导体（照片3）每个都有自己的接地电极或杆。
Photo 1 shows a section of a roof with three visible air terminals: one on the shingled ridge at the left center of the photo; one on the shingled gable at the right center; and the third on the metal chimney to the right of the gable. The main cable connecting these is also visible running from the ridge to the gable and onto the roof of the attached metal greenhouse.
（2）
Photo 2 shows the air terminal at the gable of the greenhouse with the main cable running along the ridge from the left and down the right slope of the gable at the right, toward a down conductor.
（3）
照片3显示了一个连接到砖墙并连接到接地电极的电缆的导体。
闪电保护系统的第二个组成部分是共同的接地粘结。NFPA 780的第4.14章呼吁所有接地导体和埋藏的金属导体的互连或键合，可以为闪电电流提供途径，以提供共同的地面潜力。该互连包括避雷针，电动服务，通信，天线系统和地下金属管道（水仪表的水服务，井外，管道，管道和煤气管道）。看到2009年5月“建筑问题”有关键合要求的文章corrugated stainless steel tubing (CSST)。
闪电保护系统的第三个组成部分是该建筑物的电气系统，通信系统（有线电视，警报系统，天线系统和数据电缆）的永久安装电涌保护。电涌保护必须在所有电动服务入口处安装；在通信系统的入口处；在其中任何一个离开建筑物的位置，向另一个结构提供了超过100英尺（30 m）的电缆。补充电涌保护也可以安装在分支电路面板和使用点。
Permanently installed surge protection devices protecting electric services, as well as communications systems, must be installed and grounded according to the requirements of NFPA 70国家电气密码。电涌保护装置必须通过电气系统接地导体接地，而不是直接到达闪电保护系统的向下导体。
由于这些设备是相对较新的技术，因此可以发现2000年之前安装的闪电保护系统。取而代之的是，它们可能在电气服务断开开关上安装了避雷器。1980年之前安装的系统可能既没有电涌保护也不具有闪电架。
Even though lightning-protection systems for buildings are low in cost when compared to the price of a building, many building owners and code officials are not convinced that these are necessary. After many lightning storms, there are reports to emergency services of fires, smells of smoke, and building damage. In addition, many buildings in the area will replace electrical and electronic devices (computers, televisions, telephone systems, electrical appliances, alarm system components, and even lighting fixtures) even if those buildings were not struck directly by lightning. It is a common perception that property insurance will cover the damage–but it will not cover the inconvenience during the evaluation and replacement, or the frustration of the building’s occupants if they are displaced for a week or a month while the building is repaired.
当消防员应对该州incidents involving lightning, we should note on our reports whether any lightning protection systems were installed and if they functioned properly or were damaged. Accumulation of this kind of data can lead to changes in the building and fire codes that would require these systems in all new or renovated structures.
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Gregory Havel一世S是伯灵顿镇（WI）的成员消防部门;退休的副局长和培训人员;以及30年的老兵消防。他是威斯康星州认证的消防教练II，消防官II和消防检查员；兼职讲师一世n消防网关的程序技术的大学;和safetyScherrer Construction Co.，Inc。Havel拥有圣诺伯特学院的学士学位；在设施管理和建筑建设方面拥有30多年的经验；并已在FDIC介绍课程。
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