Construction Site PPE, Water Quality and Gas Leak Detection


  1. PPEs that are required in the construction area are listed on the following text. They must be worn for the protection of personnel and to avoid disastrous accidents that may affect the projects. Safety glasses or face shields are worn any time work operations can cause foreign objects to get in the eye. For example, during welding, cutting, grinding, nailing (or when working with concrete and/or harmful chemicals or when exposed to flying particles). Wear when exposed to any electrical hazards, including working on energized electrical systems. Construction workers should wear work shoes or boots with slip-resistant and puncture-resistant soles. Safety-toed footwear is worn to prevent crushed toes when working around heavy equipment or falling objects. Gloves should fit snugly. Workers should wear the right gloves for the job (examples: heavy-duty rubber gloves for concrete work; welding gloves for welding; insulated gloves and sleeves when exposed to electrical hazards). Wear hard hats where there is a potential for objects falling from above, bumps to the head from fixed objects,or of accidental head contact with electrical hazards. Hard hats – routinely inspect them for dents, cracks or deterioration; replace after a heavy blow or electrical shock; maintain in good condition. Use earplugs/earmuffs in high noise work areas where chainsaws or heavy equipment are used; clean or replace earplugs regularly.

    Ultrasonic gas leak detection uses acoustic sensors to identify fluctuations in noise that is imperceptible to human hearing within a process environment. The sensor and electronics are able to detect these ultrasound frequencies (25 to 100 KHz),while excluding audible frequencies (0 to 25 KHz). Unlike traditional gas detectors that measure the accumulated gas, ultrasonic gas detectors “hear” the leak, triggering an early warning system. The sensors respond to sound generated by escaping gas at ultrasonic frequencies. Leak rate is mainly dependent on the size of the leak and the gas pressure. In most facilities the majority of process noise is in the audible range, while limited ultrasonic noise is generated in normal operation. Highly pressurized gas releases produce ultrasound (25 - 100 kHz)which the sensors are able to pick up despite the presence of audible noise.

    The water quality detector or detection method has the purpose of protecting water supply against accidental and intentional contamination events. This purpose is achieved first by predicting water quality parameters using the AR model. The AR model predicts future water quality parameters using recent measurements of these parameters made with automated water quality sensors. Next, a probabilistic method assigns probabilities to the time series of residuals formed by comparing predicted water quality parameters with threshold values.Finally, the D-D fusion method searches for anomalous probabilities of the residuals and uses the result of that search to determine whether the current water quality is normal or contaminated. The D-S fusion method is extended and improved by weighted averaging of water contamination evidence and by the analysis of the persistence of anomalous probabilities of water quality parameters. The extended D-S fusion method makes determinations that have high probability of being correct concerning whether or not a source of drinking water has been contaminated.