Sling Bag Inspection: What to Check Before Lifting Bulk Materials

In this article, we’ll look at the key things to check before lifting bulk materials in sling bags. From lifting loops, seams and fabric to SWL markings and rigging equipment, this guide covers the important inspection points to help identify potential issues before lifting.

Introduction

A sling bag should never be lifted simply because it looks intact.

The lifting loops, seams, fabric, identification markings and connected rigging equipment all need to be checked before the load is suspended. Damage that appears small on an empty bag can become much more serious when the bag is carrying a heavy bulk material.

A proper pre-use inspection helps identify bags that should not be lifted and reduces the risk of load failure, product loss and equipment damage.

The inspection should always be carried out by appropriately trained personnel and according to the bag manufacturer's instructions and applicable workplace requirements.

Why Sling Bag Inspection Is Essential Before Every Lift?

A sling bag carries the full weight of its contents through its lifting system. When the bag is lifted, the loops, seams and fabric are placed under load.

The Risk of Lifting a Damaged Bag

A cut, torn loop, failed seam or badly worn section can become a failure point when the bag is suspended.

The risk increases further if the bag is overloaded, lifted unevenly or exposed to sharp edges during handling.

How Pre-Use Inspection Improves Safety

A visual inspection before every lift provides an opportunity to identify obvious defects before they are placed under load.

The inspection should be part of the normal lifting routine rather than something done only when a problem is suspected.

Preventing Product and Equipment Damage

A failed sling bag can release the contents and potentially damage surrounding equipment, structures or products.

Removing a questionable bag from service is usually much safer than trying to complete one more lift with it.

For additional information on safe FIBC handling, see Bubna's guide to FIBC lifting loop styles and safe handling.

What Should Be Checked Before Lifting a Sling Bag?

The inspection should cover the complete bag, not only the lifting loops.

Lifting Loops and Attachment Points

Inspect each loop from its attachment point through its full length.

Look for cuts, broken fibres, abrasion, pulled stitching, distortion or any sign that the loop has been overloaded.

Because the loops carry the suspended load, damage to a lifting loop is a serious defect.

Stitching and Seams

Check the stitching that connects the lifting loops and load-bearing sections.

Look for skipped stitches, broken thread, pulled seams, loose sections or separation between the fabric layers.

Fabric Wear, Cuts and Abrasion

Inspect all accessible fabric surfaces for:

• Cuts
• Holes
• Tears
• Heavy rubbing
• Thinning
• Burn marks
• Distortion

Pay particular attention to areas that contact pallets, handling equipment or rough surfaces.

UV and Weather Damage

Repeated outdoor exposure can affect polypropylene over time.

Fading alone does not provide a reliable measure of remaining strength, so any sign of brittleness, cracking or significant material deterioration should be assessed against the manufacturer's requirements.

Chemical or Moisture Exposure

Certain chemicals can affect lifting materials, while prolonged unsuitable moisture or contamination can affect the bag and its components.

If the bag has been exposed to chemicals or conditions outside its specified use, it should be assessed before another lift.

Labels and Identification

The bag should have the required identification and Safe Working Load information clearly available.

If the label is missing, unreadable or inconsistent with the intended lift, the bag should not be used until the situation is resolved.

Inspect the Lifting Equipment Too

A sound sling bag does not make an unsafe lifting system safe.

The hooks, shackles, chain slings, lifting chains, crane attachments and other connected components must also be suitable, compatible and in acceptable condition.

Hooks and Shackles

Check for visible damage, distortion, cracking and correct engagement.

The attachment should fit the lifting loop without forcing, twisting or creating a sharp loading point.

Chain Slings and Lifting Chains

Chain slings should be checked for worn, stretched, bent, cracked, corroded or otherwise damaged links and fittings.

The rated capacity of the chain sling and its configuration must suit the load.

Compatibility Matters

The connection between the sling bag and lifting equipment should not pinch, cut or distort the lifting loops.

The lifting arrangement also needs to suit the bag's rated load and the method being used.

Common Defects That Can Lead to Lifting Failure

Some defects should be treated as clear warning signs rather than minor cosmetic problems.

Torn Lifting Loops

A torn, cut or heavily worn loop can lose load-bearing strength.

A damaged loop should not simply be tied, trimmed or improvised into service.

Broken Stitching

Broken stitching around a lifting loop or load-bearing seam can allow the connection to separate under load.

Fabric Deformation

Permanent stretching, distorted sections or unusual changes in the bag shape can indicate previous overloading or damage.

Excessive Abrasion

Heavy abrasion can reduce fabric or loop strength, especially where the bag has repeatedly rubbed against rough surfaces.

Heat or Chemical Damage

Burns, melted areas, brittleness, unusual discoloration or chemical attack can weaken the material.

Previously Overloaded or Damaged Bags

A bag that has already experienced a severe incident, overloading or significant impact should not automatically return to service just because no obvious tear is visible.

The condition needs to be assessed against the manufacturer's guidance.

Safe Sling Bag Handling During Lifting

Inspection is only one part of a safe lift. The lifting method also matters.

Confirm the Safe Working Load

The load weight must be known and must not exceed the bag's rated Safe Working Load.

The capacity of connected hooks, chains, shackles and other equipment must also be sufficient for the lift.

Keep the Load Balanced

The lifting arrangement should support the bag evenly and keep the load stable.

An uneven or off-centre load can place extra force on individual loops or parts of the lifting system.

Avoid Shock Loading

Sudden starts, stops or jerking movements can create forces higher than the static weight of the load.

Lifts should be controlled and smooth.

Keep People Clear

Personnel should stay clear of suspended loads and the area where a load could fall or swing.

Only trained and authorised personnel should carry out rigging and lifting operations.

For the relationship between FIBC design, Safe Working Load and safety factor, see Bubna's guide to FIBC SWL and safety factors.

Inspection Frequency and Record Keeping

A pre-use inspection is not the same as a detailed periodic inspection.

Pre-Use Inspection

The person using the bag should visually check it before the lift for obvious damage, missing identification and unsuitable conditions.

Detailed Periodic Inspection

More detailed inspections should be carried out at intervals established by the manufacturer, workplace procedures and applicable requirements.

The inspection frequency should reflect how often the bags are used and how demanding the operating environment is.

Record the Inspection

Where periodic inspections are required, records should identify the bag, inspection date, findings and any action taken.

Remove Unsafe Bags from Service

A bag that is damaged or whose condition cannot be confirmed should be clearly identified and removed from service until it has been properly assessed.

Do not return a damaged lifting bag to service based only on a visual guess or an improvised repair.

Sling Bag Inspection Checklist

Before lifting, confirm:

If any critical safety check fails, the lift should not proceed until the issue has been properly assessed.

Conclusion

Sling bag inspection should happen before the bag is placed under load, not after a problem appears.

Check the lifting loops, seams, fabric, identification, SWL and the connected lifting equipment. Also consider the load weight, balance, lifting configuration and operating conditions.

Any bag with serious damage, uncertain condition or missing required information should be removed from service until it has been properly assessed.

A consistent inspection process helps reduce lifting risks, protect bulk materials and keep the complete lifting system operating safely.

FAQ's

Q.1. Why is sling bag inspection important?

Ans. Inspection helps identify damaged lifting loops, seams, fabric and other defects before the bag is placed under load. This can reduce the risk of load failure and product loss.

Q.2. What should be checked before lifting a sling bag?

Ans. Check the lifting loops, stitching, seams, fabric, identification markings, SWL and the condition and compatibility of the connected lifting equipment.

Q.3. How often should sling bags be inspected?

Ans. A visual pre-use inspection should be performed before lifting. Detailed periodic inspections should follow the manufacturer's instructions, workplace procedures and applicable requirements.

Q.4. When should a sling bag be removed from service?

Ans. Remove it from service when there are significant cuts, torn loops, damaged load-bearing seams, serious abrasion, heat or chemical damage, missing required identification or any other condition that makes its safe use uncertain.

Q.5. Can damaged lifting loops be repaired?

Ans. Do not improvise repairs to load-bearing loops. Any repair or return to service should follow the manufacturer's approved procedure and applicable requirements.

Q.6. What defects are most common in sling bags?

Ans. Common warning signs include loop damage, broken stitching, fabric cuts, abrasion, chemical or heat damage, deformation and missing identification.

Q.7. Should lifting chains and slings also be inspected?

Ans. Yes. The complete lifting system should be checked. Chains, hooks, shackles and other rigging components must be suitable, compatible and in acceptable condition.

Q.8. What is the difference between a pre-use inspection and a scheduled inspection?

Ans. A pre-use inspection is a quick check for visible defects and suitability before a lift. A scheduled inspection is a more detailed examination carried out at defined intervals under the applicable inspection programme.

Q.9. Who should inspect sling bags?

Ans. Pre-use checks should be carried out by trained personnel who understand the bag and lifting system. Detailed inspections should be performed by a competent or otherwise qualified person as required by the applicable rules and manufacturer's instructions.

Q.10. How can inspection improve lifting safety?

Ans. Regular inspection identifies defects before they become load failures. It also helps ensure that damaged bags and incompatible lifting equipment are removed from use.