We manufacture a cellulose powder product, which is a combustible dust. We need to have an SDS that we send to customers, and it is GHS compliant.
If your product has no hazardous components, then US law does not require an SDS.
But, this is for a UK customer, and your laws there may be different, especially after BREXIT. So I would ask your customer for a reference to the UK standard that governs SDS requirements and check it out.
If they are only asking because they get it for things like flour and sugar, which contain combustible dust, then they may think they need it for everything.
I would have a conversation with the person who sent it to you so you can satisfy what they need. A letter stating that there are no hazardous materials in your product may be enough.
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