Proper chemical storage is essential for safety and to ensure that chemicals remain unspoiled. Improper storage is not only hazardous, but it is also bad for quality control and in some cases illegal.
Chemicals can be impacted by elements like heat, cold and pressure – and the materials used to make tanks can be impacted by the chemicals themselves.
Each chemical has its own storage requirements that must be met. Storage tanks differ in design and engineering depending on what they store.
For example, we wouldn’t use a metal tank to store nitric acid because it would eat the metal, but we would use a metal tank to store water.
It’s important to consider the following when choosing storage tanks:
- The chemical / substance being stored
- Product requirements
- Design and maintenance
- All relevant regulations (safety, environmental, health)
If these are not considered in the engineering and design of storage tanks, you run the risk of improper, unsafe and illegal storage.
What is being stored?
When choosing chemical storage tanks you can start with what is being stored. This will determine what the tank is made from and the design specifications of the tank, such as the pressure it will operate at and the valves required.
However, if you choose a tank based on only size and material without considering the specific properties of the chemical, you might not achieve optimal performance.
For example, while some acids can be stored in the same tank, some acids like hydrofluosilicic acid require a special fuming system. Other chemicals need insulation or a special tank liner if they are made from stainless steel.
Regulations and design standards
There are laws in place that set out regulations for the storage of certain chemicals and substances. For example, flammable liquids and chemicals that are hazardous have to be stored and labelled in a certain way.
With regards to employers, the most relevant regulations fall under the Control of Substances Hazardous to Health Regulations (COSHH). This requires employers to follow good practice when storing and handling chemicals.
For flammable liquids stored in tanks, the relevant regulations fall under the Dangerous Substances and Explosive Atmospheres Regulations 2002.
With regards to tank design, BS EN 12573:2000 sets out standards for welded static non-pressurised thermoplastic tanks. Another relevant standard is BS 4994, which sets out the specification for storage tanks in reinforced plastics.
Regular testing and maintenance
The regular testing and maintenance of chemical storage tanks is essential to ensure that the tanks continue to function as intended.
This is a requirement by law as set out in the regulations described above where hazardous and dangerous chemicals are stored.
You need to determine the frequency of testing and the method of inspection for each container. Testing and maintenance should only be performed by people with appropriate qualifications. You may need to outsource this.
Tests could include pressure tests, tracer chemical tests to determine leaks, visual inspections and tightness tests. The purpose of tests and inspections is to ensure that the tanks haven’t deteriorated and are safe to use.