Leak integrity

As expected, the good parts all passed both the leak integrity test and the aerosol challenge test. 

All 30 of the poor seal samples failed the leak integrity test, as expected. None of the 30 poor seal samples failed the aerosol challenge test. Failure of all 30 poor seal samples was expected in the aerosol challenge test. 

The results of this correlation study demonstrate that the leak integrity test is more challenging test than the aerosol integrity test, a standard industry package integrity test, as it was more sensitive at detecting flaws in LYOGUARD trays. 

Many check valves are only designed to seal bubble tight and not provide a high leak integrity. Parts inside check valves are subject to wear and check valves should be checked frequently for proper operation. 

The panels with the greatest leak integrity are welded together entirely. Often this is not desirable since components such as valves and regulators may have to be replaced. Use of vacuum type face-seal connections with metal sealing washers are often used to achieve good leak integrity, and ease of assembly operation. Components installed on this type of panel often have these face-seal connections welded directly on them to minimize the points of potential leaks. 

The hydrostatic test is, in one sense, a method of examination of a vessel. It can reveal gross flaws, inadequate design, and flange leaks. Many beheve that a hydrostatic test guarantees the safety of a vessel. This is not necessarily so. A vessel that has passed a hydrostatic test is probably safer than one that has not been tested. It can, however, stiU fail in service, even on the next appheation of pressure. Care in material selection, examination, and fabrication do more to guarantee vessel integrity than the hydrostatic test. 

Solvent/fume leak- Maintain integrity of gaskets and seals age from casing, gaskets compatible with process materials joints resulting in loss of heck mating faces for corrosion/unevenness, containment. particularly on clad components ... 

Use corrosion resistant material of construction Implement mechanical integrity program to prevent leaks of corrosive material Use multiple voting with plausibility analysis... 

Check for plant integrity/flammable leaks periodically or continuously on-line, as appropriate Install appropriate fire/smoke detection, audible alarms Provide adequate fire suppression systems Deal with mishaps such as spillage immediately... 

Check weight Test tor leaks Check integrity... 

Failure of the integrity of the DjO system in sequence 5 resulted from a small leak in the DjO system and failure of the operating personnel to isolate the leak which dominated the sequence. The probability of the small leak that challenges of the tank used to pressurize seals for the main circulating pumps was estimated to be 0.5 0.21 g. 

Some Class I BSCs are equipped with an integral exhaust blower the cab inet blower must be tiiterloclced with the building exhaust fan. In the event that the building exhaust fan fails, the cabinet exhaust blower must also turn off so that the exhaust ducts are not pressurized. If the ducts are pressurized and the HEPA filter develops a leak, contaminated air could be discharged into other parts of the building or the environment. 

The main problem in preventing fires and explosions is thus preventing the process material from leaking out of the plant, that is, maintaining plant integrity. Similarly, if toxic or corrosive materials are handled, they are hazardous only when they leak. 

The materials selection procedure for new or replacement plant is crucial to the safe and economic operation of that plant. There is no one correct way to select the appropriate construction material, since for small plant handling toxic or inflammable products the integrity of the plant is high in priority, whereas large plant producing bulk material in a competitive market is more likely to be made of cheaper constructional materials, and the occasional leak or failure may have fewer safety implications. 

J. Bissell, D. Acker, and L. R. Quaife. Pipeline leak-location technique utilizing a novel test fluid and trained dogs. In Proceedings Volume, number 9. 5th Pipe Line Ind Pipes Pipelines Int Pipeline Pigging Integrity Monit Int Conf (Houston, TX, 2/1-2/4), 1993. 

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