The Interagency Language Roundtable (ILR) created the ILR Language Proficiency Scale as a tool to measure linguistic proficiency of United State Government employees by an objective system applicable to all languages.
This is not a test to critique your language proficiency, rather a helpful tool to assess your proficiency in a particular language to determine at what level you are equiped to interact directly with limited English proficient clients. ILR also has developed a scale to assess interpretation performance and translation performance on a professional level.
PDFs of the Listening, Speaking and Reading ILR Self Assessements are attached.
In addition, the Asian & Pacific Islander Institute on Domestic Violence developed a checklist for bilingual speakers who may be asked to interpret for their client as a guide to when it is okay to act as the interpreter and when an advocate shouldn't act as an interpreter for their client. The checklist is attached and utilizes the ILR Self Assessment Language Proficiency Scale.