Traceability
Many of us in the scientific and technological arenas are measurement middlemen taking measurements provided by others, and making measurements for others. This discussion is intended to explore traceability and the value of accreditation in the context of the rapidly changing global marketplace of measurements and measurement services:* Measurement users and measurement makers need first to find out how accurate their measurements must be, that is, how much uncertainty they can tolerate in their measurements.* Requiring measurements to be traceable using the current international definition of traceability can provide assurance that measurements meet accuracy needs.* Because the task of determining whether measurements are traceable can be somewhat formidable and time consuming, there is enormous value added by requiring accreditation of measurement providers.
I see Certification in context mostly as where one company 'certifies' another or where a company 'certifies' a product or other output where the 'certification' is their statement (promise) that something complies with something. When I think of certification I also think of a C of C which used to just be a statement of compliance/conformance (everyone asks for data now...). I see Accrediation in context of 'An Accreditation Board', whether for colleges or other businesses (there are 5 entries for ACCREDIT in my dictionary). The general thrust is 'To give credit or authority to' and 'to confer credit or authority on'.