Some industry-specific standards include guidance for contamination control planning for oxygen systems. Yet not all of them do. Even so, oxygen cleaning is required to meet all sectors’ safety and quality assurance standards.
Consequently, system operators and technicians should follow validated plans for oxygen system maintenance. Such plans should always include coordinating an appropriate oxygen cleaning service schedule. This is fundamental to oxygen system operation whether regulators mandate it or not.
Why Invest In Cleaning Equipment For Oxygen Service?
Cleaning equipment for oxygen service is vital to oxygen system safety. It can also prevent system, seal, and component damage. This safeguards against premature system failure and protects product purity.
Prioritizing Oxygen System Cleanliness When Oxygen Cleaning Is Not Required
The benefits of high-quality oxygen cleaning services are straightforward.
- Systems not subject to appropriate oxygen cleaning procedures accumulate oxides and debris. This increases their vulnerability to mechanical malfunction and uncontrolled ignition during normal operation.
- Systems that receive timely and meticulous oxygen cleaning services are different. They do not accumulate contaminants or risk to the same degree or in the same way. This supports a safe workplace, preserves equipment, prevents environmental pollution, and protects end-users.
These explain the value of cleaning equipment for oxygen service. Operators should clean to reduce operational risk, not just to comply.
What Regulations Say About When Oxygen Cleaning Is Required
Oxygen cleaning procedures are an obvious priority among regulators. This is despite the lack of cleaning schedule mandates in regulatory literature.
Evidence of this is present in the abundance of validated methods to test systems for oxygen service cleanliness. That said, there are few nuanced requirements for when oxygen cleaning is required. The only common standard is to clean whenever system cleanliness falls below expected levels.
Commonalities Across Oxygen System Maintenance Standards
Though they do not mandate oxygen system maintenance schedules, current standards define:
- Quantifiable levels of cleanliness; and
- What methods, solvents, and equipment are necessary to achieve certain levels of cleanliness.
Some standards contain other recommendations. Most recommend how to test a system for oxygen service cleanliness at a desired level, if not when.
Recent revisions to industry standards established equivalency across sectors. They also created a deferential hierarchy between regulators. This encourages agility in oxygen system maintenance planning. It also explains the anemic recommendations for oxygen cleaning service schedules.
Guidance For System Operators Who Ask “When Is Oxygen Cleaning Required?”
It is challenging to create an oxygen system maintenance schedule based on regulations alone. Regulators’ guidelines for when oxygen cleaning is required are broad by design.
The planning standards that do exist for cleaning equipment for oxygen service share some features. In particular, they crystallize around specific handling and machining processes. These are likely to deposit contaminants regardless of industry, system design, or application. Contaminants can be residues, fibers, particles, or oil/grease.
Notably, this includes oxygen cleaning procedures. Inadequate oxygen cleaning services may contaminate a system. With use, solvents and detergents become impure. Inexperienced technicians may not use good solvents or properly rinse/drain components.
Which Oxygen Systems Require Professional Cleaning
Even at ambient conditions, oxygen can react with other elements and compounds. Increasing pressure, temperature, and/or O2 concentration makes oxygen even more volatile. This increases the danger of uncontrolled reactions.
Most industrial oxygen systems operate with elevated volatility.
Flammable or combustible contaminants in already reaction-prone systems can cause catastrophic uncontrolled reactions. Additionally, even inflammable contaminants increase the risk of mechanical malfunction. Each of these can alter system operation and internal purity.
Consequently, requirements and recommendations for cleaning equipment for oxygen service apply broadly. That is, they are relevant for any component or system involved in the production, storage, use, transportation, or distribution of liquid or gaseous oxygen. This includes:
- Cylinders and cylinder valves;
- Regulators, vaporizers, compressors, and pumps;
- Stationary storage tanks;
- Tank trucks and tank cars;
- Pressure vessels (like heat exchangers and rectification columns);
- Any/all associated piping/pipelines, valves, and instrumentation.
General Guidelines For When Oxygen Cleaning Is Required
Cleaning equipment for oxygen service rarely follows a standard schedule. Still, it is fundamentally necessary for oxygen system operation. Operators should expect oxygen cleaning to be required throughout any oxygen system’s useful life.
Oxygen system maintenance plans activate cleaning protocols in two scenarios. Often, this is because of oxidation within the system during normal operation. Additionally, oxygen cleaning is required whenever handling, packaging, or maintenance contaminates the system.
Instances when oxygen cleaning is required may include:
- During manufacture, especially before packaging;
- After transport, especially if components arrive without secure, clean packaging;
- During/following construction, especially when cleanroom construction is not feasible;
- During/following installation, especially when tools are not clean;
- Following routine maintenance, especially when breaching a closed system, welding, or cutting;
- If the system needs rust- or scale-removal, plating, or recoating; and
- If the system fails inspection.
Why Maintain An Oxygen System Beyond Compliance?
Oxygen cleaning services are most effective when they are both timely and meticulous. It follows that any firm’s interest in cleaning equipment for oxygen service should go beyond compliance. Unclean (or improperly cleaned) oxygen systems are simply a preventable hazard.
Moreover, the cascading risk posed by unclean oxygen systems threatens chain losses for any firm. Contamination can cause uncontrolled ignition, damage components, and diminish product quality. These can then lead to:
- System failure;
- Fires and explosions;
- Increased oxygen system maintenance costs;
- Loss of productive time and profits;
- Damage to reputation and market share; and
- Personnel injury and loss of life.
Testing To Know When Oxygen Cleaning Is Required
During regular system operation, consistency is important in oxygen system maintenance schedules. Their testing interval depends on system application and risk.
Increased contamination risk should increase test frequency. Periods of high contamination risk include construction, component installation/repair, and cleaning.
System operators should also verify the need for cleaning equipment for oxygen service as needed. Plans to test a system for oxygen service cleanliness should preempt mechanical malfunction. If not, operators should determine whether more frequent or different testing is necessary. Reports of operational errors/accidents should also prompt verification.
When & How To Test A System For Oxygen Service Cleanliness
Regardless of industry, recommendations for when and how to test a system for oxygen service cleanliness include:
- Visual inspections;
- Particulate sampling; and
- Testing for non-volatile residue.
On visible and normally accessible interior surfaces, discoloration, and fluorescence show contamination. These are visible in white-light testing, black-light testing, and wipe tests. These processes are ideal for use at regular intervals as well as for ad hoc testing.
Tape lift and solvent wash sampling are also ideal high-frequency tests for oxygen service cleanliness.
Get High-Quality Oxygen Cleaning Services
PFC's oxygen cleaning protocols comply with the highest industry standards. Yet system applications inform our methods for cleaning equipment for oxygen service in any system.
That is how Precision Fabrication and Cleaning always provides high-quality oxygen cleaning services. Contact us today to find out more.
Sources:
- Sgobba, Tommaso et al. Safety Design for Space Systems. Oxford: Elsevier Science & Technology, 2009. Print.
- https://www.valvemagazine.com/web-only/categories/technical-topics/6658-oxygen-cleaning-a-validated-process-is-critical-for-safety.html
- https://link.springer.com/chapter/10.1007/978-1-4615-5285-7_11
- https://engmag.in/cleaning-oxygen-service/
- https://www.nata.aero/agso/astgcache/c2307c64-28e5-44e0-8962-92af344649bc.pdf
- https://snebulos.mit.edu/projects/crater/file_cabinet/0/01002/01002_10_r-m.pdf
- https://www.nasa.gov/centers/wstf/testing_and_analysis/oxygen_systems/oxygen_service_cleaning.html
- http://edge.rit.edu/edge/P18102/public/Testing/Safety%20Protocols/Documents/ASTM_OxygenCleaning.pdf