What is bunding for hazardous chemical storage?

A bund is a secondary containment structure designed to capture any hazardous liquid that escapes from a primary container, such as a drum, IBC, or bulk storage tank. In practice, this usually means a dedicated base and surrounding walls sized to contain leaks, spills, and overfills before they can enter the environment.

For operators handling flammable or otherwise hazardous substances, bunding is a core control measure that supports compliance with UK environmental and health and safety legislation.

Bunding requirements in the UK

In the UK, the Control of Pollution (Oil Storage) Regulations 2002 (COP10) set out key expectations for secondary containment when storing hazardous liquids. As a general rule of thumb, a bund is required for:

• Storage facilities holding more than 3 m³ of hazardous flammable liquids; or
• Storage facilities holding more than 6 m³ of hazardous non-flammable liquids.
• Barrel and Drums holding hazardous liquids over 200L

Where a bund is required, typical good practice includes:

• Bunding capacity: The bund volume should be at least 110 % of the largest container or tank within the bunded area. This ensures that a failure of the largest single vessel is fully contained.
• Freeboard allowance: A minimum freeboard (spare height above the design containment level) of around 0.3 m to limit overtopping due to wave action or rainfall.
• Impermeable base and walls: The bund floor and walls should be impermeable to the stored substance to prevent migration into soil, drains, or watercourses.

Site-specific requirements may also arise from an environmental permit, COSHH assessment, DSEAR assessment, or insurer standards, so it is important to verify the exact duties applicable to your operation.

How Kovobel supports bunding standards

Kovobel is a leading manufacturer of modular, customisable storage containers designed for demanding industrial environments. Our hazardous chemical storage range is engineered to support compliance with UK bunding expectations while delivering practicality, durability, and ease of relocation.

Kovobel’s bunded storage containers are suitable for a variety of hazardous substances, including:

• Flammable liquids such as fuels and solvents
• Corrosive materials such as acids and alkalis
• Oxidising agents and other hazardous process chemicals

Bunds are constructed from robust, impermeable materials and designed to provide reliable secondary containment with capacities aligned to the volume of the stored containers.

For larger installations, Kovobel can supply bunded storage systems that scale with your requirements, including:

• Bunded containers configured for multiple IBCs or drum pallets
• Modular units that can be combined to create segregated storage areas
• Integration with fixed structures where additional bunding is required

Additional safety measures for hazardous chemical storage

Bunding is only one part of a safe hazardous substance storage strategy. Many operators enhance their risk controls by adding monitoring and protection systems to their Kovobel containers.

Important note: The additional systems listed below are not supplied as standard by Kovobel. They are usually sourced from third-party specialists such Tank Express and installed after the container has been assembled on site.

• Overfill prevention systems – Automatically shut off flow into a tank or container when a preset level is reached, helping to prevent overfilling and loss of containment.
• Vapour detection and monitoring – Continuously monitor vapour concentrations around storage areas and provide early warning of leaks or gas releases.
• Leak detection and alarm systems – Detect liquid within the bund or under tank bases and raise alarms so incidents can be contained and cleaned up quickly.
• Fire suppression systems – In flammable liquid stores, fire suppression systems can automatically activate to control or extinguish a fire, supporting site emergency response plans.

When combined with properly sized bunding and suitable ventilation, these measures support a high level of protection for people, property, and the environment.

Why choose Kovobel bunded storage containers?

Kovobel’s hazardous chemical storage solutions are designed for organisations that need reliable, relocatable, and compliant facilities. Key advantages include:

• Compliance-ready design – Bund capacities and construction support UK regulatory expectations for hazardous liquid storage.
• Durable construction – High-quality materials and engineering for long service life in demanding environments.
• Modular and portable – Containers can be relocated, expanded, or reconfigured as operational needs change.
• Customisable layouts – Internal racking, segregation, and access options to match your process and housekeeping requirements.
• Sustainability focus – Reusable, modular units help reduce waste associated with traditional fixed-build storage structures.

In conclusion

Bunding is a fundamental requirement for safe hazardous chemical storage in the UK. By providing robust secondary containment, bunds reduce the risk of spills, protect the environment, and support regulatory compliance.

Kovobel’s custom-built bunded storage containers combine engineered containment with modular, relocatable design. When paired with appropriate third-party monitoring and protection systems, they provide a strong platform for managing hazardous substances safely and responsibly.

For help specifying a bunded storage container to match your inventory, site layout, and compliance obligations, contact the Kovobel team.