02. Air Flushing

Air flushing provides an efficient method of removing debris from pipelines and newly constructed systems.

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In the gas process lines, the velocity should be the lowest figure between 60 m/s and the velocity obtained at 1.3 time the maximum process flow rate. The minimum velocity should be 30 m/s.
In liquid process lines, a velocity between 30 m/s and 60 m/s should be used.

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Air Blowing 과 같이 청소을 목적으로 합니다. Air Blowingr과 Air Flushing의 차이라면 Air Blowing은 압력을 채워 한번에 배출하고, Air Flushing은 연속적으로 순환시켜 오염물질을 청소하는 것으로 이해하시면 될 것 입니다. 사용되는 방법으로 Air / Steam / Water / Manual / Pigging 등의 여러가지가 있습니다. 아래 JSA는 Air Blowing 큰 차이는 없으니 참고하세요.

Air Flushing

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Hazard Category	Hazards	Controls
Injury to Pesonnel and Property Damage	1. As a result of low safety awareness or incorrect information 2. Non compliance of safety regulation & procedures	1. Obtain correct PTW 2. Task supervisor to conduct pre-start meeting on daily basis and discuss all relevant hazard to the job with the crew and what corrective action are required before/during and at completion of job and sign attendance sheet. 3. Task supervisor to explain JSA to all employees and sign attendances sheet 4. Confirm that procedures and other associated documents are approved and available.
Slips and Trips	1. Cause by inadequate access and poor visibility	1. Ensure proper wind up of hoses and housekeeping at work site. 2. All work areas are to be kept clean and free of tripping hazards. 3. The accessories (hoses & pump) not being used must be disconnected and store separately 4. Adequate lighting for night work is to be provided or when lighting is poor
Serious or Fatal Injury	1. Accidentally sudden release of air pressure & debris from discharge end of pipe or any valve spindle gland, gasket and flange 2. Defective tools can damage equipment and damaged equipment can leak due to high pressure	1. Barricade the area where air blowing test is to be carried out 2. Post warning signs 3. Appropriate PPE (Personnel Protective Equipment) such as safety helmet, safety glasses, leather gloves and safety shoes shall be worn by all employees 4. Ensure the equipment and tools to be used for air flushing (such as hoses, pump, couplings, pressure gauges, gasket etc.) are free from any defect and suitable for the pressure rating of the system 5. Whiplash arrestor must be installed with every joint of hose connector.
Stuck or Hit to personnel	1. Can occur sudden release of air pressure & debris	1. During the testing operation all non essential personnel will be kept out of the test area 2. Provide barricade and signages to prevent entry of unauthorized personnel
Physical Injury from flying debris	1. Flying foreign particles from pipe	1. Pressure gauge must be installed to monitor the allowable pressure 2. A screen should be provided at least 2 meter away from the open end pipe to protect the foreign particles to hit soneone. 3. The area must be cordoned off