Columbia subject headings:
Industrial hygiene--Law and legislation--United States.
Industrial hygiene--United States--Bibliography.
Industrial hygiene--United States--Directories.
Industrial safety--Law and legislation--United States.
Industrial safety--United States--Bibliography.
Industrial safety--United States--Directories.
Harvard subject headings:
Industrial hygiene--Law and legislation--United States
Industrial hygiene--United States--Bibliography of bibliographies.
Industrial hygiene--United States--Bibliography.
Industrial hygiene--United States--Directories.
Industrial safety--Law and legislation--United States
Industrial safety--United States--Bibliography of bibliographies.
Industrial safety--United States--Bibliography.
Industrial safety--United States--Directories.
Princeton subject headings:
Industrial hygiene--Law and legislation--United States.
Industrial hygiene--United States--Bibliography.
Industrial hygiene--United States--Directories.
Industrial safety--Law and legislation--United States.
Industrial safety--United States--Bibliography.
Industrial safety--United States--Directories.