21. Leak test of Pipes

The leak test involves filling the pipe system with a liquid, usually water, which may be dyed to aid in visual leak detection, and pressurization of the pipe to the specified test pressure. Pressure tightness can be tested by shutting off the supply valve and observing whether there is a pressure loss. The location of a leak can be visually identified more easily if the water contains a colorant. Strength is usually tested by measuring permanent deformation of the container. 

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Hazard Category	Hazards	Controls
Injury to personnel & Property Damage	1.As a result of low safety awareness or incorrect information 2. Non compliance of Safety Regulations & HSE Procedure	1. Obtain correct PTW (Permit To Work). 2. Daily basis pre-start meeting. 3. Task supervisor to explain JSA to all employees
Serious or Fatal Injury	1. Defective tools can damage equipment and damaged equipment can leak. 2. Due to use of tools and equipment without inspection	1. Ensure the equipment and tools to be used for hydro testing (such as hoses, pressure gauges etc) are free from any defect and suitable for the pressure rating of the system. 2. All equipment and tools shall be inspected by qualified person 3. Barricade the area where leak- test is to be carried out and post warning signs  4. Appropriate PPE (Personnel Protective Equipment) shall be worn by all employees
Hit and Struck to Person	1. Can cause by sudden release of fluid pressure from any valve spindle gland, gasket adn flange	1. Ensure the pressure relieving device is calibrated at maximum allowable pressure 2. During the testing operation all non essential personnel will be kept out of the test area  3. Monitor the pressure gauges from a safe distance away from the potential source of high pressure such as valves, joints etc. 4. Never increase the leak  test pressure more than the maximum allowable pressure for the weakest portion in the segment or pressure rating of the hoses. 5. Do not leave the pressurized hoses or pipes unattended when the leak-test is going on.
Suffocation	1. Can occur that worker can suffocate, if the area is not ventilated and fresh air is not moving inside the location of work area 2. Leak of nitrogen gases from cylinder valve or the connection line can reduce the oxygen percentage in that area	1. Nitrogen cylinder should be in standing position, secured with cradle or trolley, valves, gauges in good condition,  no leaks around the valve or connection lines   2. Nitrogen cylinder must be located in open ventilated area

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