What are the disadvantages of point-source detectors?
a. Does not reflect the actual gas concentration in the entire area b. Some types are subject to poisoning by materials such as silicon, halogen, and metal-organic compounds. This is a dangerous and unrevealed mode of failure. c. The gas must reach the specific detector (accuracy will be compromised if the detector is placed incorrectly or too few are used). d. Slow response e. May not reflect actual gas concentration in case of high air flow/wind directed not towards the detector. f. Frequent maintenance required to check calibration g. In large open areas in order to provide adequate coverage, a substantial number of detectors is required.
