Bulkheads and Receptacles Cleaning Techniques

Receptacles refer to packaged devices with optical ports. Many receptacle devices use lens based systems which are less sensitive to contamination as opposed to fiber, but can be damaged if cleaned improperly. If you inspect a receptacle device and are not able to focus on the endface cladding, then you have a lensed device and should not attempt to clean it. See Figure 1 and Figure 2 for sample images of the endface core and cladding.

We has found that the use of swabs for cleaning is not always very effective even for experienced operators. It might be better to leave an optical port alone unless signal effecting contamination is observed blocking the core. Contaminants can be pushed onto the endface in the process of the insertion of the swab.

Caution: Wet cleaning is not recommended for bulkheads and receptacles. Damage to equipment can occur.

Always make sure you plug in a clean mating connector in order to avoid cross contaminating the receptacle side. Ground in contamination is much harder to remove than loose debris. Remember, inspect first and clean only if necessary!

• Dry Clean: Lint-Free Swabs

This section describes dry cleaning techniques that uses lint-free swabs.

Tools

• Lint-free swabs

Figure 1

 Caution: Never clean bulkheads or receptacles without a way to inspect them afterwards. Cleaning can actually leave the endface in a worse condition.

 Caution: Read the reminders and warnings before you begin this process.

1. Make sure that the lasers are turned off before you begin the inspection.

 Warning: Invisible laser radiation might be emitted from disconnected fibers or connectors. Do not stare into beams or view directly with optical instruments.

2. Remove the protective endcap and store it in a small resealable container.
3. Inspect the fiber connector in the adapter or bulkhead with a fiberscope probe. Refer to the Connector Inspection Technique section.
4. If the adapter is dirty, select the appropriate lint-free swab according to the connector ferrule size.
5. Inspect the connector in the adapter again with a fiberscope probe.
6. Insert the clean lint-free swab into the adapter. See Figure 2.

Figure 2

7. Turn the swab several complete revolutions in the same direction.
8. Properly dispose of the swab. Never reuse a swab.
9. Repeat the cleaning process as necessary.

• Wet Clean: Lint-Free Swab

Caution: Improper cleaning can cause damage to equipment. The primary concern with the use of isopropyl alcohol is that it can be removed completely from the connector or adapter. Residual liquid alcohol acts as a transport mechanism for loose dirt on the endface. If the alcohol is allowed to evaporate slowly off the ferrule, it can leave residual material on the cladding and fiber core. This is extremely difficult to clean off without another wet cleaning and usually more difficult to remove than the original contaminant. Liquid alcohol can also remain in small crevices or cavities where it can re-emerge during fiber connection.

Caution: On female multifiber connectors, ensure no alcohol gets into the guide pin holes or it can come out during mating and contaminate your connection.

Tools

• 99% isopropyl alcohol
• Lint-free swabs

Caution: Never clean bulkheads or receptacles without a way to inspect them afterwards. Cleaning can actually leave the endface in a worse condition as alcohol residue is one of the most difficult contaminants to remove.

1. Make sure that the lasers are turned off before you begin the inspection.

 Warning: Invisible laser radiation might be emitted from disconnected fibers or connectors. Do not stare into beams or view directly with optical instruments.

2. Remove the protective endcap and store it in a small resealable container.
3. Inspect the connector with a fiberscope. Refer to the Connector Inspection Technique section.
4. If the dry cleaning procedure did not remove the dirt from the fiber endface, then place one drop of 99% alcohol to lightly moisten a new lint-free swab. Do not oversaturate the swab.

Tip: Have a dry lint-free swab available for drying immediately after the cleaning. Make sure that the drying swab stays clean. See Caution

5. Lightly press and turn the dampened swab to clean the ferrule face.
6. Immediately after you clean, lightly press and turn the second swab (dry) to dry any alcohol that remains from the ferrule face.
7. Properly dispose of the wet and dry swab. Never reuse a swab.
8. Inspect the connector again.

Related Knowledge:

• Cleaning Techniques for Pigtails and Patch Cords
• Bulkheads and Receptacles Cleaning Techniques
• Patch Cord Contamination Conditions Sample Images
• Patch Cord-Inspection and Cleaning are Critical
• Other materials of Fiber Optic Patch Cable