本研究結合雙向無線通訊技術、氣體感測技術、電子控制技術、網路傳輸技術、資料庫管理技術，並利用自行設計的雙向無線通訊協定（Listen-Talk-Quiet protocol, 簡稱LTQ），開發了一套新型勞工工作活動模式即時監測系統（The Wireless-based Worker Exposure Assessment System, 簡稱WES），其功能包括可即時偵測勞工工作時的工作位置、停留時間與暴露濃度，同時當系統發現勞工暴露量超過警戒值時，亦可發佈個人化暴露警報。 本系統利用無線通訊不易受物體直接阻隔的特性，改善了舊有紅外線勞工定位系統非常容易因為通訊視線（line of sight）受遮蔽而影響定位性能的問題；同時本系統的定位範圍為小功率的半徑3.5公尺與大功率的半徑6公尺區域，亦改善了紅外線定位系統因為定位範圍小而在中、大尺度工作區域佈點困難的問題。 透過無線模擬軟體的測試結果顯示，在LTQ協定運作下，單一區域定點子系統在5秒內約可提供36個勞工配戴子系統進行至少1次的通訊，實測的結果亦顯示1秒內單一區域定點子系統約可提供10台勞工配戴子系統至少進行1次的通訊。WES系統基本性能測試結果顯示，系統的定位正確率可高達96%~99%。在時間-活動模式性能的測試中，系統所記錄的時間-活動模式資料與人工觀察標準方法間的相關性（r2）高達0.95~0.99，顯示本系統應可取代人工直接觀察的方式，以進行勞工工作活動模式的調查與監測。以上結果驗證了本研究開發的系統已具有實用價值。 A wireless worker exposure assessment system (called WES) was developed for worker’s time-activity studies in indoor workplaces. By using a special designed wireless data transmission protocol - Listen-Talk-Quiet Protocol, or LTQ, the WES is able to assign up to 16384 distinct identification numbers to different workers and can detect more than 36 workers concurrently located in one communication area in less than 5 seconds. Meanwhile, monitoring data, such as worker’s identifications, locations, and exposure concentrations, are continuously transmitted to the server for storage and calculations. When worker’s exposure exceeds predefined alert limit, the server will send out a warning message to the specific worker and trigger a personal alarm. The WES can cover 38.5m2 area(3.5m in radius) while setting in low power mode, and cover 113m2 area(6m in radius) while in high power mode. Both provide sufficient coverage for studying exposure patterns in most workplaces. Software simulations indicated that the LTQ protocol has sufficient capacity to provide communication channels for 36 works in 5 seconds. In addition, laboratory tests showed that more than 10 works were able to talk to the host communication station (WES_Ht) every second. The reproducibility tests indicated that the WES achieved 99% accuracy in determining the positions of workers. The laboratory tests showed that the durations of a particular worker staying in a specific area measured by the WES method were highly correlated with that obtained by the direct observation method (r2=0.95~0.99). The results demonstrated that the WES is capable to be a great tool for worker’s time-activity pattern survey.
