The results presented in this paper demonstrate that TRM-0522 is a useful and reasonably representative reference material for use in marine DOM biogeochemistry. We note that use of the existing marine DOC CRM as a DOM standard is technically feasible, but consider this to be an inefficient option: assuming a typical DOC concentration of 0.5 mg L -1 , a C content of 50 %, and an extraction efficiency of 50 %, a 1 mg DOM extraction would require 100 x 20 mL vials at a cost of $140 USD. TRM-022 is currently available at a cost of approximately $25 USD per 1 mg, and has been well characterised using several common high-resolution methods (NMR; HRMS: UPLC-HRMS/MS). Thus, TRM-022 fills a resource gap for a DOM-specific marine reference material.