环境传感器包括各种传感器，包括监测天气、路面、水位和空气质量状况的传感器。这些传感器通常连接到附近的微处理器，称为远程处理器单元（RPU）。环境传感器站（ESS）由RPU及其传感器套件组成。通常，该设备永久性地位于旅行走廊沿线的现场。在某些情况下，“站”可能是便携式的，甚至是移动的。在本标准中，所有三种类型的站点都称为ESS。在交通领域，这些设备经常被用于改善道路维护和交通运行。

Environmental sensors include a wide array of sensors, including those that monitor weather, roadway surface, water level and air quality conditions. These sensors are typically connected to a nearby microprocessor termed a Remot Processor Unit (RPU). An Environmental Sensor Station (ESS) consists of the RPU plus its suite of sensors.Typically, this equipment is permanently located at a site along a travel corridor. In some cases, the "stations" may be portable, or even mobile. For the purpose of this standard, all three types of stations are called ESS. In the transportation community, these devices are frequently used in order to improve roadway maintenance and traffic operations.