How to Properly Store Flat Slings to Prevent Abrasive Wear and Chemical Damage

A flat sling completes a lift in a harsh environment. It is covered in grit, oil, and chemical residue. The crew tosses it into the storage locker—a dark, damp corner of the warehouse. Six months later, the sling is retrieved for a critical lift. It looks fine on the surface. But the fibers have been silently degrading from moisture and chemical exposure.

This scenario is preventable. Lishenflex has been manufacturing synthetic flat slings for decades, and our field data show that storage conditions are one of the most overlooked factors affecting sling service life. Proper storage prevents abrasive wear, chemical damage, UV degradation, and mildew—and it costs nothing more than a little organization.

1. Why Storage Matters: The Four Threats

Flat slings are vulnerable to four primary environmental threats during storage. Understanding each is the first step toward prevention.

1.1 Abrasive Wear During Storage

Abrasion is not limited to lifting operations. Slings stored in contact with rough surfaces—concrete floors, metal shelving, or each other—can experience surface abrasion over time. According to Lift-All, slings should be stored so that they do not rub against each other or come into contact with sharp edges.

Storage practice: Store slings on rounded racks or smooth shelves. Avoid stacking slings directly on concrete floors where grit and moisture can embed in the webbing.

1.2 Chemical Damage During Storage

Chemical damage is often invisible—the sling may look normal while the fibers have already lost significant strength. The CCOHS states that nylon slings are damaged by acids, while polyester slings are damaged by alkalis. Chemical fumes and vapors can degrade slings even without direct liquid contact.

Storage practice: Never store slings in areas where chemicals, fumes, or vapors are present. Keep slings away from acid storage, plating lines, battery rooms, and cleaning chemical storage areas.

1.3 UV Degradation During Storage

Ultraviolet radiation from sunlight degrades synthetic fibers over time. According to the Rigging Institute, round slings with light-colored jackets can lose up to 40 percent of their ultimate strength over a six-month period of continuous UV exposure.

Storage practice: Store slings in a dark, shaded area away from windows and skylights. If slings must be stored in a location with natural light, use opaque covers or cabinets.

1.4 Mildew and Moisture Damage

Wet slings stored in dark, damp conditions are vulnerable to mildew growth. CERTEX Denmark specifies that slings which have become wet should be hung up and allowed to dry naturally before storage. The CCOHS lists mold, mildew, and rotting as conditions requiring immediate removal from service.

Storage practice: Never store a wet sling. Allow slings to air dry completely in a well-ventilated area before placing them in storage.

2. Proper Storage Conditions

2.1 Location

Per CERTEX Denmark and the CCOHS, slings should be stored in a cool, dry, well-ventilated area:

• Away from direct sunlight and UV radiation

• Away from heat sources (steam pipes, radiators, open flames)

• Away from chemicals, fumes, and corrodible surfaces

• Away from dampness and basements prone to moisture

2.2 Position

• Hang slings on rounded racks or lay them flat on smooth shelves

• Do not fold slings under pressure—permanent creases create weak points

• Do not pile slings directly on top of each other in a way that causes friction

• Keep slings off the floor—use pallets or racks

2.3 Protection

• Use opaque covers if slings must be stored where light is present

• Label storage areas to ensure slings are returned to the correct location

• Separate damaged slings from serviceable inventory—damaged slings should be destroyed to prevent accidental reuse

3. Inspection Before Storage

CERTEX Denmark requires that slings be inspected for any damage that may have occurred during use prior to placing in storage. Damaged slings must be withdrawn from service—they should never be returned to storage.

Pre-storage inspection checklist:

• Cuts, tears, snags—any exposure of core fibers?

• Abrasive wear—is the webbing width reduced?

• Stitching—any broken or worn stitches?

• Chemical damage—any discoloration, stiffness, or brittleness?

• Heat damage—any melting, charring, or glazing?

• UV damage—any fading or bleaching?

• Identification tag—legible and intact?

Lishenflex’s lab data confirm that slings with even minor damage—if stored and later returned to service—experience accelerated failure compared to undamaged slings. This is why pre-storage inspection is not optional.

4. Storage Do‘s and Don’ts

5. Summary and Practical Recommendations

Proper storage of flat slings is not an afterthought—it is a critical part of a comprehensive sling maintenance program. Abrasive wear, chemical damage, UV degradation, and mildew can all occur during storage, silently reducing sling strength and creating safety hazards.

Key takeaways:

1. Store clean and dry—never store a wet sling

2. Store in a cool, dark, well-ventilated area—away from UV, heat, and chemicals

3. Keep slings off the floor—use racks or shelves

4. Inspect before storage—damaged slings must be removed from service

5. Separate damaged inventory—destroy retired slings to prevent reuse

6. Label storage areas—ensure slings are returned to the correct location

Lishenflex manufactures polyester flat slings to EN 1492-1 and ASME B30.9 standards, with clear color-coded capacity markings and load-bearing stitching. Our products are designed for durability, but proper storage is essential to maximizing service life and maintaining safety.

If you need assistance establishing a sling storage and maintenance program for your facility—or need help determining whether your current storage practices are adequate—please send an email to sales@lishenflex.com, and our technical team will provide one-on-one support.