1.1本规程涵盖了确定安装在机场交通管制塔（ATCT）中的玻璃厚度，以抵抗指定的设计荷载，选择的断裂概率小于或等于设计风荷载首次出现时每1000 1 lite或每1000 4 lite。 1.2本程序适用于规定载荷不超过10 kPa（210 psf）的普通向外倾斜驾驶室玻璃设计。 1.3本程序假设控制塔驾驶室玻璃的纵横比不大于2。 1.4程序假设控制塔驾驶室玻璃的面积不小于1.86平方米（20平方英尺）。 1.5本程序仅适用于矩形或梯形退火单片玻璃、退火层压玻璃或退火中空玻璃。 1.6程序的使用假设如下: 1.6.1安装在ATCT中的退火单片和退火夹层玻璃应沿两个平行边缘、任何三个边缘或所有四个边缘具有连续的横向支撑； 1.6.2中空玻璃应沿四个边缘具有连续的横向支撑； 和 1.6.3受支撑的玻璃边缘应简单支撑，并可在平面内自由滑动。 1.7本程序不适用于任何形式的有线、图案、蚀刻、喷砂或表面处理降低玻璃强度的玻璃。 1.8本程序不适用于任何形式的热处理玻璃、化学强化玻璃或任何类型的表面处理旨在提高玻璃强度的玻璃。 1.9本程序旨在确定厚度和结构类型，以在选定的断裂概率下抵抗指定的设计风荷载。 最终确定的玻璃厚度和结构也取决于各种其他因素（见5.3）。 1.10这些程序不涉及玻璃上的爆炸荷载。 1.11以国际单位制表示的数值应视为标准值。括号中给出的值是英寸-磅单位的数学转换，仅供参考，不被视为标准值。 1.12 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 ====意义和用途====== 该标准程序有助于确定玻璃结构的厚度，以抵抗具有选定断裂概率的指定设计载荷。 本标准程序涉及以下玻璃结构:退火单片玻璃、退火层压玻璃和用退火单片玻璃或退火层压玻璃或两者制造的中空玻璃。 使用这些程序假设: 玻璃没有边缘损坏，并正确上釉， 玻璃没有被滥用， 玻璃的表面状况是已使用数年的典型玻璃，由于暴露表面上的轻微磨损，其明显弱于新制造的玻璃， 玻璃边缘支撑系统具有足够的刚度，可将所支撑玻璃边缘的横向挠度限制在其长度的1/175以下。该计算应使用规定的设计荷载，以及 玻璃偏转中心不得导致边缘支撑损失。 通常，将玻璃偏转中心保持在标称玻璃厚度的三倍或以下，可以确保不会出现边缘支撑损失。 许多其他因素影响玻璃类型和厚度的选择。这些因素包括但不限于:热应力、风载碎片的影响、过度偏转、玻璃碎片破碎后的行为、地震效应、热流、边缘咬合、噪音消除、潜在的破碎后后果等。 此外，联邦、州和地方建筑规范中规定的考虑因素以及安全玻璃标准中提出的标准和现场具体问题可能会控制最终的玻璃类型和厚度选择。

1.1 This practice covers the determination of the thickness of glass installed in airport traffic control towers (ATCT) to resist a specified design loading with a selected probability of breakage less than or equal to either 1 lite per 1000 or 4 lites per 1000 at the first occurrence of the design wind loading. 1.2 The procedures apply to common outward sloping cab glass designs for which the specified loads do not exceed 10 kPa (210 psf). 1.3 The procedures assume control tower cab glass has an aspect ratio no greater than 2. 1.4 The procedures assume control tower cab glass has an area no less than 1.86 square metres (20 square feet). 1.5 The procedures apply only to annealed monolithic, annealed laminated, or annealed insulating glass having a rectangular or trapezoidal shape. 1.6 The use of the procedures assumes the following: 1.6.1 Annealed monolithic and annealed laminated glass installed in ATCTs shall have continuous lateral support along two parallel edges, along any three edges, or along all four edges; 1.6.2 Insulating glass shall have continuous lateral support along all four edges; and 1.6.3 Supported glass edges are simply supported and free to slip in plane. 1.7 The procedures do not apply to any form of wired, patterned, etched, sandblasted, or glass types with surface treatments that reduce the glass strength. 1.8 The procedures do not apply to any form of heat treated glass, chemically strengthened glass, or any type of glass with surface treatments intended to increase the glass strength. 1.9 The procedures address the determination of thickness and construction type to resist a specified design wind load at a selected probability of breakage. The final glass thickness and construction determined also depends upon a variety of other factors (see 5.3). 1.10 These procedures do not address blast loading on glass. 1.11 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard. 1.12 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== This standard procedure facilitates determination of the thickness of a glass construction required to resist a specified design load with a selected probability of breakage. This standard procedure addresses the following glass constructions: annealed monolithic, annealed laminated, and insulating glass fabricated with annealed monolithic or annealed laminated glass, or both. Use of these procedures assume: The glass is free of edge damage and is properly glazed, The glass has not been subjected to abuse, The surface condition of the glass is typical of glass that has been in service for several years, and is significantly weaker than freshly manufactured glass due to minor abrasions on exposed surfaces, The glass edge support system is sufficiently stiff to limit the lateral deflections of the supported glass edges to less than 1/175 of their lengths. The specified design load shall be used for this calculation, and The center of glass deflection shall not result in loss of edge support. Typically maintaining center of glass deflection at or below the magnitude of three times the nominal glass thickness assures that no loss of edge support will occur. Many other factors affect the selection of glass type and thickness. These factors include but are not limited to: thermal stresses, the effects of windborne debris, excessive deflections, behavior of glass fragments after breakage, seismic effects, heat flow, edge bite, noise abatement, potential post-breakage consequences, and so forth. In addition, considerations set forth in federal, state, and local building codes along with criteria presented in safety glazing standards and site specific concerns may control the ultimate glass type and thickness selection.