FAA Order 8130.34D — UAS Operating Limitation A-22
Appendix A · p. A-5
UA flight operations may not involve carrying hazardous material, as defined in Title 49 of the Code of Federal Regulations (, or the dropping of any objects or external stores.
Carrying hazardous materials or dropping objects or external stores is prohibited unless all operational risks have been sufficiently mitigated as required by , and the hazmat requirements in 49 CFR have been met, if hazmat will be carried. The operator/applicant must provide to the FAA acceptable procedures for hung stores and loss of control link while carrying stores. A similar case must be made for hazmat carried aboard the aircraft and, if approved, will be listed in the special provision section of the COA, or in the operating limitations.
Verify it yourself: the eyeball above opens the exact page of Order 8130.34D with this limitation highlighted.