Silos are critical assets across South Africa’s agricultural and industrial sectors, used to store grain, cement, and other bulk commodities. Due to their size, age, and continuous exposure to mechanical loads and environmental conditions, silos are inherently high-risk structures. Regular, systematic inspections are therefore essential to ensure structural integrity, operational reliability, and most importantly, human safety.
Over time, silos deteriorate as a result of concrete cracking, corrosion of steel components, foundation settlement, vibration from loading and unloading operations, and moisture ingress. If left undetected, these defects can escalate into serious structural failures, including wall collapse, roof failure, or malfunction of discharge systems. Routine inspections enable early identification of deterioration, allowing asset owners to plan corrective maintenance, reduce lifecycle costs, and extend the service life of these capital-intensive structures.
From a safety perspective, silos present multiple hazards, including falls from height, entrapment in flowing material, engulfment during unloading, and the risk of dust explosions. Grain dust is highly combustible, and poor housekeeping or inadequate ventilation significantly increases explosion potential. Structural defects can further amplify these risks by compromising access systems such as ladders, platforms, walkways, and handrails.
South Africa has experienced several serious silo-related incidents that highlight the consequences of insufficient inspection and access control. Fatal accidents involving workers and unauthorised persons falling into silos have been reported, particularly in rural and agricultural communities. In several cases, structural weaknesses or the absence of adequate safety barriers contributed directly to these incidents.
Beyond the tragic loss of life, such events expose asset owners to legal liability, regulatory action, operational disruption, and reputational damage. Inspections also play a critical role in protecting product quality. Undetected moisture ingress, pest infestation, or internal lining damage can result in contamination, spoilage, and significant financial losses. Regular inspections demonstrate due diligence and support compliance with South Africa’s occupational health and safety legislation.
Case example: Ageing agricultural silo facility
At an ageing agricultural silo facility in South Africa, undetected structural deterioration led to a serious operational safety incident. Over time, cracks developed at the upper concrete shell and roof interface due to moisture ingress, cyclic loading, and inadequate maintenance. These defects were not identified early, as inspections were infrequent and limited to ground-level visual observations.
During routine filling operations, uneven material pressure acted on the weakened structure, creating unsafe internal conditions and increasing the risk of partial structural failure. A post-incident assessment revealed that early warning signs—including surface cracking, spalling, and corrosion staining—were present but located in hard-to-reach areas at height.
These defects could have been safely and efficiently identified through drone-based inspections, which provide high-resolution visual data without exposing personnel to fall hazards or requiring costly scaffolding and shutdowns. Drone inspections enable rapid assessment of the full silo envelope, including roofs, vents, upper wall sections, and external fittings.
Following the incident, a professional structural engineer’s report was required to assess the extent of the damage, verify load-bearing capacity, and determine whether continued operation was safe. The engineer’s findings confirmed that earlier detection would have significantly reduced repair costs, operational downtime, and risk exposure.
This case demonstrates the value of combining routine drone inspections with formal structural engineering assessments. Together, they provide a safe, efficient, and cost-effective inspection strategy that enables early defect detection, informed decision-making, regulatory compliance, and the prevention of incidents that can result in injury, asset damage, or business disruption.
Sky-Futures Africa turns inspections into asset intelligence—delivering actionable risk, performance, and compliance insights faster, cost-effective and safer than traditional inspection methods.
Contact Eben at ekoen@sky-futures.com for more information.
