Hazardous chemical manufacturing covers production involving substances classified as very toxic, toxic, harmful, corrosive or irritant under the GB CLP Regulation. Not every contract manufacturer is set up to handle these substances safely, so confirming this capability is one of the first things to check if your product falls into a hazardous category.
Key points
- The Control of Substances Hazardous to Health Regulations 2002 (COSHH) require employers to assess and control exposure to hazardous substances, including liquids, solids, fumes, dusts and vapours.
- Hazard categories under COSHH and CLP include very toxic, toxic, harmful, corrosive and irritant classifications.
- A manufacturer handling hazardous chemicals needs appropriate risk assessment, exposure control, health surveillance and incident planning in place.
- Hazardous chemical manufacturing capability often overlaps with other specific capabilities such as flammable liquid manufacturing or toxic material handling.
What This Capability Involves
A manufacturer with hazardous chemical manufacturing capability has the facilities, training and management systems to safely produce substances classified as hazardous to health, including appropriate personal protective equipment, ventilation and containment systems, and documented COSHH risk assessments for the specific substances handled.
When You Need This Capability
You need a manufacturer with this capability if your product formulation, or its raw materials or intermediates, is classified as very toxic, toxic, harmful, corrosive or irritant under CLP. This applies across many sectors covered on this site, from agrochemicals to cleaning chemicals and beyond.
Regulatory Considerations
COSHH requires employers to prevent or adequately control exposure to hazardous substances, through risk assessment, exposure control measures, health surveillance where appropriate, and incident and emergency planning. A manufacturer should be able to demonstrate their COSHH risk assessment approach for your specific formulation, not just a generic policy statement.
How Manufacturers Control the Risk
Hazardous handling capability rests on a hierarchy rather than on any single measure. The strongest controls are engineered - closed transfer systems, contained charging, local exhaust ventilation, automated dosing that removes the operator from the point of exposure. Below those sit procedural controls, and below those personal protective equipment, which is the last line rather than the primary answer.
That hierarchy is a useful diagnostic when assessing a manufacturer. A site whose answer to a hazardous material is principally about what operators wear is describing a weaker position than one that explains how the material is contained, transferred and monitored. See COSHH responsibilities for the framework this sits within.
What This Means for Your Project
Hazard classification narrows the field of available manufacturers before anything else does, so establishing it early saves considerable time. Sending safety data sheets for all inputs at first contact lets a manufacturer rule themselves in or out immediately rather than after several conversations.
Expect hazardous work to carry a cost premium and a longer onboarding period. Containment, monitoring, health surveillance and waste handling all cost money, and introducing a new hazardous substance to a site usually requires assessment before a first batch can be scheduled. Building that into the project timeline is more realistic than treating it as an administrative delay.
Questions to Ask a Manufacturer
- What experience do you have handling substances with our specific hazard classification?
- What COSHH risk assessment and control measures do you have in place for this type of product?
- What personal protective equipment and containment systems does your facility use?
- Do you provide health surveillance for staff handling hazardous substances?
Related Pages
Frequently Asked Questions
Does every contract manufacturer handle hazardous chemicals?
No - this requires specific facilities, training and risk management, so confirm a manufacturer's direct experience and COSHH compliance approach rather than assuming general chemical manufacturing capability extends to hazardous substances.
Is "hazardous" the same as "flammable" or "explosive"?
Not necessarily - hazardous chemical classifications under COSHH and CLP cover toxicity, corrosivity and irritancy, which is broader than flammability or explosion risk, though a product can fall into more than one category. See flammable liquid manufacturing for that specific risk.
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Search the DirectoryLast reviewed: August 2026. Regulation and guidance change — verify anything you rely on against the primary source. Tell us if something here is out of date.