By: John Ferrari, P.Eng., P.M.M.
Storage rack fundamentals
Steel storage racks are often mistakenly considered a commodity but don’t let their unassuming appearance fool you – not all racks are created equal! Storage racks are the backbone of all industrial warehouses. Prior to putting a rack system into service, no storage rack should be approved for use unless all three pillars – engineering design, manufacturing and installation – comply with applicable standards and regulations. Let’s focus on the first two as they are so closely intertwined for producers of these systems.
Storage racks are high-performance structures whose perforated frame posts and unique beam connectors require critical physical testing prior to an engineer putting pen to paper. Rack storage systems must be properly designed to support the tens of thousands of pounds of product that is typically stored above warehouse employees. As new buildings grow in height, so do the racks. The design challenge shifts to not only ensuring sufficient load-bearing strength, but stability as well so that the racks do not overturn, especially in areas of the country that are prone to earthquakes. Design standards are developed to protect the public by setting minimum requirements for acceptable levels of safety. The Canadian Standards Association (CSA) published the CSA S16-14 (Update 1) steel design standard containing a new Annex ‘N’ titled, ‘Design and Construction of Steel Storage Racks’ in December of 2016. Standards become enforceable by building officials once they are referenced within provincial building codes. With several key Canadian provinces recently adopting the CSA S16-14 (Update 1) in their current building codes, storage racks must now be compliant with requirements contained within its Annex N.
Steel made simple
Making steel is similar to baking a cake. To achieve a desired grade of steel, one must follow a precise recipe; should you dare to deviate, you risk compromising the quality of the finished product. Beginning with iron and adding various ingredients or elements in different proportions will determine what type of steel is made. The properties of the resulting steel – strength, ductility, weldability, etc. – can suffer if the recipe is not properly adhered to and one cuts corners in steel composition or production. To adhere to material standards, reputable rack manufacturers will source specific steel formulations from reputable steel producers to ensure that their engineered rack designs will perform as intended in the field. While commercial quality steels are a general-purpose steel grade, they are not recommended for structural applications where the mechanical properties of the steel are of paramount importance. Structural quality steel is produced to exact specifications under highly controlled conditions, eliminating variability and inconsistencies in strength and quality. In Canada, steel storage racks should be constructed using steel of structural quality and fabricated within a facility certified by the Canadian Welding Bureau (CWB) to the CSA W47.1 standard.
Ask and you shall receive
While many rack manufacturers produce components with certified steel and qualified welders, there are some who do not. Prior to selecting your rack vendor, conduct proper due diligence. Don’t be afraid to ask the tough questions. To ensure that the storage system adheres to current applicable design and engineering standards, the rack user must be provided documentation by the supplier that establishes capacity, configuration and use of the rack. The documentation must originate from the rack manufacturer to ensure authenticity. Consider making the purchase order conditional on receipt of certified material test reports, or mill test reports, that stipulate the specific standards from the CSA or ASTM that the steel is compliant with. These documents validate the steel’s chemical composition and mechanical properties. Ask for a copy of the rack manufacturer’s Letter of Validation from the Canadian Welding Bureau acknowledging that the fabricating facility is certified to CSA Standard W47.1. If you struggle receiving adequate information prior to releasing a purchase order, it could be a sign of things to come. Don’t settle for anything less. As a user of a storage rack system, you are ultimately responsible for providing a safe work environment to your employees and this can be attained by ensuring that your suppliers are meeting their regulatory obligations.
Quality, integrity, compliance
The overall safety and integrity of a rack structure can be in jeopardy when critical items of its design and manufacturing process do not meet recognized standards. In Canada, rack frames and beams must bear an identification mark traceable to the manufacturer. Without knowing the source of the rack, it becomes difficult to verify that the engineering design will be accepted by building officials, that the steel is of structural quality and that the welding was performed by qualified personnel adhering to Canadian standards. The risk of a rack collapse resulting from a sub-standard product is real and will amount to incalculable expenses associated with worker injuries (or deaths), product loss, facility damage, lost productivity and more.
As a best practice, all documentation and technical specifications of a rack system should be reviewed and approved by a qualified professional engineer prior to its purchase. By doing so, it will help ensure that the rack system in consideration will be safe and meet required standards. This process, however, can have its own pitfalls as well. Not many engineers are well-versed in the design of these unique structures. It is important to ask for an engineer’s qualifications and experience related to storage racks. Items to consider may include the engineer’s years of experience related to the design and engineering of storage rack, number and scope of projects completed, range of oversight including assessment of and adherence to material and manufacturing standards.
On your next rack purchase, don’t be short-changed. Be sure to conduct your due diligence and demand compliance with all applicable Canadian engineering and manufacturing standards, and remember . . . not all racks are created equal.
About the author – John Ferrari, P.Eng., P.M.M.
John is a Professional Engineer with over 25 years of experience in the design of steel storage rack systems for many of the largest warehouses and distribution centres in North America. He is highly regarded in the material handling industry for both his leadership and technical expertise as the SVP – Engineering with Konstant, Canada’s foremost steel rack manufacturer. As Chair of the CSA S16-14 Rack Structures Workgroup and member of the Rack Manufacturers Institute’s Specification Advisory Committee, John continues to contribute to the development of key industry standards and regularly presents educational sessions on the safe use and maintenance of these high-performance structures.