Having a front row seat to the Pacific Ring of Fire is both a blessing and a curse for New Zealand. It gives us our thermal springs, hot water beaches and spectacular volcanoes, but it also puts us at risk of earthquakes, some of which are devastating.
Built tall, constructed from steel columns and beams, and stacked with heavy inventory, warehouse racking can be particularly vulnerable during seismic events – unless it’s specifically designed and engineered for the task.
Seismic safety is an absolute non-negotiable for NZ warehouses. Your storage system needs to be capable of holding up against whatever earthquake risks your local area faces.
In this guide we’ll dive into seismic racking systems to gain a deeper understanding of earthquake-proof racking in NZ: what it is, how it works, and what you need to know about implementing a system in your own warehouse.
How earthquakes impact warehouse racking systems
Earthquakes impart both lateral and vertical forces on warehouse racking. If these forces are particularly strong, or if they happen to match the racking’s resonant frequency, they can lead to a number of structural failures:
- Upright buckling: Vertical frames can deform or collapse under lateral seismic loads, especially if they haven’t been properly braced or anchored or lower grade materials have been used in the steel or fastenings.
- Dislodged beams: Beams can become unseated from their connectors due to shaking.
- Toppling: Entire racking systems can tip over if they aren’t properly secured to the floor, or if they’re loaded in a way that makes them particularly top-heavy.
- Base plate/anchor failure: Anchors securing the rack to the slab can loosen or shear off, leading to instability and potential toppling.
- Joint and connector failure: Weak or poorly designed connections between components can fail under stress.
The consequences of failure can be significant, extending far beyond the destruction of the racking. You can face damaged/destroyed inventory, extensive business interruptions, and at worse, worker injury or death.
Seismic racking systems offer a way to avoid these fates.
What is seismic-rated racking?
Seismic-rated or earthquake-resistant racking is designed to handle the often violent shaking that can compromise the structural integrity of your warehouse storage system.
Key features of seismic racking systems include:
- Cross-bracing and frame design: Increases lateral stability and limits to a controlled sway during seismic events.
- Heavy-duty base anchoring: Securely bolts the rack to the floor to prevent uplifting and unwanted movement
- Reinforced uprights and beams: Components featuring thicker steel (or higher grade steel) and stronger connections with bracing design
- Seismic isolators or dampers: These can be used to help absorb and dissipate the energy of the earthquake.
Seismic racking also relies on loads being evenly distributed, to ensure weight is balanced across the rack, reducing stress on any one part.
NZ standards and compliance requirements for racking safety
Racking safety in New Zealand is governed by a combination of building standards and workplace safety legislation:
- Building standards: Warehouse racking systems must comply with the NZ Building Code and the structural load requirements of NZS 1170.5, which ensure racking structures can withstand local seismic activity.
- The Health and Safety at Work Act (HSWA): These more general guidelines task warehouse owners and operators with ensuring that all storage systems are safe for use and don’t pose a hazard to workers or visitors.
In order to demonstrate compliance with these building and safety standards, your racking should be designed by experts and certified by a qualified structural engineer. This certification is often required for building consent, insurance coverage and, if an incident were to occur, to avoid liability.
Who needs earthquake-proof racking in New Zealand?
The NZ Building Code and NZS 1170.5 require seismic assessment and design, even in regions with lower seismic activity. But seismic considerations are particularly important in areas that sit on major fault lines, like Christchurch, Wellington, Hawke’s Bay and Marlborough.
Some types of warehouses are also more at risk than others, such as those with high-bay racking, or that deal in heavy or irregular loads. In short, if you utilise racking in your warehouse, you need to consider how it will handle local seismic risks.
Seismic risk assessment: what warehouse managers should check
As a warehouse manager you can conduct a basic inspection of the earthquake resistance of your racking, to gain an understanding of whether it needs to be reinforced or replaced. Begin by checking:
- Age and installation method: Older racking systems may not meet current seismic standards or may have been installed without proper engineering approval.
- Anchoring and bracing: Check that all racks are securely anchored to the floor and have cross-bracing or other structural reinforcements that help them to resist shaking.
- Load capacity vs seismic zone classification: Check that your current racking can handle both the weight of inventory and the seismic risks of your region.
Ultimately seismic risk assessments are a job for specialist structural engineers and racking experts, so the wisest path forward is to engage with a consultant.
Benefits of investing in seismic-rated racking systems
Why bother with seismic protection in your warehouse? Perhaps a more pertinent question is ‘what happens if warehouse racking fails in an earthquake?’ By preparing your warehouse racking for earthquakes, your business will be in a far better place, for the following reasons:
- Reduced risk of injury or death: Most importantly, seismic-rated racking systems keep your people safe.
- Compliance: Avoid fines and potential litigation by ensuring your racking is up to scratch.
- Protection of stock and infrastructure: Keep your inventory and assets safe, and avoid costly downtime.
- Lower insurance costs and liability: By investing in safety you can enjoy lower premiums and more complete insurance coverage.
- Peace of mind: Seismic-rated racking simply gives you one less thing to worry about.
Storepro: seismic-compliant racking experts
New Zealand’s position on the boundary of two tectonic plates gives us much of the stunning nature we’re famous for, from thermal springs to active volcanoes. But in the confines of a warehouse, it also brings risk.
At Storepro we can help you navigate the maze of NZ seismic compliance and requirements, to ensure your warehouse racking system can handle whatever Mother Earth might throw at it. Our expert team is ready to offer all the seismic guidance you need, from inspecting and retrofitting your current racking, to designing a new system from scratch.
Get in touch with our friendly team today for a free consultation, and take the first step towards stronger, safer and smarter storage.