Environmental monitoring—it’s all around

Environmental monitoring depends on distributed monitoring solutions to cover areas that, in most cases, don’t require real-time updates, making wireless networks suitable for communicating with central data repositories. Should the monitoring system also be required to support alarms when thresholds are exceeded, most wireless protocols now support interrupt messages that provide this capability. Consequently, wireless is natural fit for environmental monitoring applications to protect the environment, processes/equipment and people.

When we think about environmental monitoring, most of us visualize distributed sensor suites located almost anywhere to monitor ambient air quality around industrial facilities for regulatory reporting and compliance, or across municipalities to provide the data now included in many weather reports. A second type of widely distributed environmental monitoring system monitors water quality with typical measurements reported to regulatory authorities, including pH, turbidity, chemical concentrations and flow rates in effluent streams. Municipalities are also interested in levels in storm drains to manage runoff without flooding.

When an anomaly is detected in ambient monitoring stations, the search for the source begins, which is where onsite monitoring systems come into play. Many of these in-plant systems are permanently wired to the control system, but not always.

Tracking sources for potential ambient/environmental as well as hazardous gas emissions is normally done with point detectors, which require engineering knowledge for probable dispersion scenarios around likely sources such as pump seals or tank farms. Because tank farms tend to be geographically dispersed, they’re a good application for wireless sensors.

Wireless, ultrasonic, acoustic detectors can be deployed along pipelines or process boundaries to detect leaks across a larger area, and triangulate the source of releases. Because these detectors are spaced farther apart, and are less likely to be near a control cabinet, they too are well-suited to using wireless sensor network technology. This technology helps identify leaks in their early stages to reduce environmental impact, and improve safety by identifying leaks before they escalate into incidents such as dangerous concentrations or fires.

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Wireless sensors can also be used in mobile and temporary installations, including real-time transmission of data from aerial platforms. They can be used to manage rights-of-way for abnormal situations with technologies such as light detection and ranging (LiDAR), spectral imaging, and gas and ultrasonic detectors.

All these detectors protect workers by providing information on potential risk areas to reduce worker exposure, so they can take additional protective measures before entering hazardous areas, beyond the portable detectors they normally wear.

Wireless networks and sensors are also ideal for temporary monitoring setups during construction, shutdowns or remediation projects for perimeter monitoring because they’re easy to deploy and relocate without extensive infrastructures.

Individual, personal monitors worn by workers entering hazardous areas typically have detectors for up to five gases also monitor for lack of motion and report back to central location so that emergency responders can rescue a “worker down” that may otherwise go undetected.

One less obvious way that wireless sensor networks support environmental goals is by monitoring energy consumption as inputs to building or facility energy management systems. They optimize production against energy usage to balance the ratio of different energy forms used, and send those commands to the facility’s control system. A second non-intuitive way that wireless contributes to environmental stewardship is by integrating equipment monitoring for predictive maintenance. This method prevents failures resulting in safety issue, such as increased emissions via a leak or integrity failure, or a reduction in expected equipment life, requiring earlier replacement and associated resources.

These are just a few ways that wireless  allows us to monitor almost anything all the time, and support environmental stewardship by understanding and responding to what this information tells us about the world around us.