Understanding Pallet Racking Beams: Safety, Compliance & Inspection
- mattb645
- 3 days ago
- 2 min read
When it comes to pallet racking safety, beams are one of the most critical components. They carry the weight of your pallets day in and day out. Over time, beams can bend under load—a little bending is normal, but too much deflection is a clear sign of danger. That’s why beam deflection is a key check during any pallet racking inspection.
What Is Beam Deflection?
Beam deflection is the amount a beam bends when loaded. There are two main types of deflection inspectors look for:
Vertical Deflection (Sagging): The beam sags downward in the middle when carrying load.
Horizontal Deflection (Inward/Outward): The beam twists or bows sideways, moving toward or away from the pallets.
Both types must be kept within safe limits to ensure compliance with AS 4084-2023 Steel Storage Racking.
How to Measure Beam Deflection
Vertical (Sagging) Deflection
Run a taut string or straight edge along the underside of the beam.
Load the beam to its working weight.
Measure the gap at the midpoint.
Compare to the maximum allowed deflection.
Horizontal (Inward) Deflection
Place a straight edge vertically along the front face of the beam.
Measure any inward or outward bend at the midpoint.
Compare to the maximum allowed deflection.
The Allowable Deflection Limits
Australian Standards use the L/180 rule for vertical deflection and a stricter L/350 rule for inward deflection.
Vertical Deflection (Sagging): Beam length ÷ 180 = Maximum vertical deflection
Horizontal Deflection (Inward/Outward): Beam length ÷ 350 = Maximum horizontal deflection
Example (Beam Length = 2,500 mm)
Vertical: 2,500 ÷ 180 = 13.9 mm (max sag allowed)
Horizontal: 2,500 ÷ 350 = 7.1 mm (max inward bend allowed)
If the measured deflection exceeds either of these limits, the beam is unsafe and must be unloaded and replaced.
Quick Reference Table
Beam Length (mm) | Max Vertical Deflection (mm) | Max Horizontal Deflection (mm) |
2,000 | 11.1 | 5.7 |
2,500 | 13.9 | 7.1 |
3,000 | 16.7 | 8.6 |
3,500 | 19.4 | 10.0 |
Excessive sagging weakens the load capacity and can lead to collapse.
Inward bending can cause pallets to slip or beams to disengage.
Regularly checking both types of deflection ensures compliance with AS 4084 and protects your people, stock, and equipment.
