After years of drafting and reviews, the Federal Highway Administration (FHWA) has issued a final rule that updates and revises its highway bridge inspection standards for the first time since 2009.
The newregulation, published in the Federal Register on May 6, was mandated by the 2012 Moving Ahead for Progress in the 21英石世纪法（MAP-21）。
MAP-21规定中的一个重点是FHWA使用“基于风险的”方法来修改桥梁检查要求，而该方法是该机构新标准的主题。
FHWA在其联邦登记册通知中说，基于风险的方法“通过运用其经验和工程知识来确定有限资源以更优化的方式在其库存中确定有限资源的使用，从而为桥梁检查组织提供了额外的灵活性。”
Matt Reiffer, American Council of Engineering Cos. vice president of infrastructure programs, says, “This framework ensures qualified inspectors on every job, empowers the exercise of professional engineering judgment and provides the necessary flexibility for addressing the most pressing areas of concern and allocating limited resources.”
Reiffer said in emailed comments to ENR that many of ACEC's recommendations were included in MAP-21 and reflected in the final version of the FHWA standard.
Those recommendations include "rigorous professional licensing and training requirements for bridge inspectors and a risk-based, data-driven approach to inspection intervals," he said.
新标准的重要规定就检查之间所需的最小间隔。
通常，现在必须检查一次桥梁一次。州运输部（DOTS）可以寻求FHWA的批准时间超过24个月。最大是48个月。一些桥梁需要12个月的间隔。
根据新标准，有一些国家点和其他检查组织的选项，允许常规检查间隔长达48个月，水下检查最多72个月。
设置检查间隔的两个选项
FHWA's new standard offers state DOTs two main options for interval-setting: Method 1, which the agency said in its published notice, uses "a simplified assessment of risk," and Method 2, which it says uses "a more rigorous assessment of risk."
方法1要求国家点制定标准，以确定何时必须比每24个月更频繁地进行检查，因为桥梁的年龄，状况评级，交通水平和负载等因素。
当桥梁的甲板，上层建筑，子结构或涵洞组件的额定情况严重或更糟糕的情况下，方法1还需要至少12个月的间隔，或者在FHWA的尺寸为零至9的情况下的评分为3或更少。
另一方面，在方法1下，如果桥梁的主要组件被评为满意或更高（六个或更高），则可以长达48个月。
Method 2 is more complicated. It calls for states to form a "risk assessment panel," to determine a bridge's risk level.
That panel would have at least four members, at least two of whom are professional engineers.The group also must have knowledge of a variety of bridge-related subjects, such as design, inspection, maintenance, materials and construction.
当时，小组制定的间隔政策和标准必须提交给FHWA以供批准。
各州，部落政府和其他联邦机构均未锁定方法1或2。FHWA官员在通过电子邮件回复ENR问题的回复中说，这些实体可以选择与桥梁或子集或新利18备用他们的整个库存 - 方法的选择取决于他们。”
哪种方法将被更广泛地使用？FHWA发言人在通过电子邮件回答Enr的问题的回答中说：“很难预测。”新利18备用“方法1几乎与他们现在所做的事情相同，因此实施要容易得多。”
But the official also said that "Method 1 cannot result in the same efficiencies that are possible using Method 2."
发言人补充说：“我最好的猜测是，随着时间的流逝，我们将看到从方法1转到方法2的转变，以获取更多常规的桥梁构造类型，例如仪表板板，或类型的检查，例如例行检查，非冗余钢张力构件或水下。
没有新的无人机检查要求
FHWA的联邦公报通知还涉及无人空中系统或无人机，近年来，该系统已广泛用于桥梁检查。
在其新的桥梁检查标准中，FHWA并未指定UAS检查的新要求。但是它确实指出，检查无人机的运营商必须遵守其他法定和监管要求，例如管理公共飞机的要求。
例如，FHWA说，在整个检查过程中，必须进行UAS辅助桥梁检查的团队负责人
The agency also leaves the door open to issuing further guidance on drones used in bridge inspection. It said in its Federal Register notice, “FHWA will continue to look for opportunities and integrate these tools when it is believed they will contribute to the continued success of the bridge inspection program.
The new standard's other provisions also include mandatory qualifications for inspection program managers and team leaders and requirements for bridge inspectors' training.
它还将术语重命名为“骨折 - 关键成员”为“非冗余钢张力构件”。
为什么要漫长的等待？
MAP-21 directed that the new inspection standards be completed within three years of its July 6, 2012, date of enactment.
当被问及为什么最终的桥梁检查规则花了很长时间才能生产时，FHWA官员说，规则制定过程始于2012年11月，但被MAP-21的“变革性质”推迟了。
FHWA官员说，其中包括美国运输部的授权，要求签发“大量规则制定”。
发言人指出，其中之一是FHWA于2015年发布的首个国家隧道检查标准。
The official said the agency prioritized the tunnel inspection standards as well as "other rulemakings needed to support MAP-21," given that the bridge inspection standard was in place and "already working successfully."
