MB ChB Manch 1925, MD 1936; MRCS LRCP 1925; DPH Eng 1930.
Firth studied at Manchester and was house surgeon at MRI before being appointed assistant medical officer for Withington Hospital Manchester. Firth was later medical officer for Hastings Municipal Hospital and consultant physician at Brighton General Hospital. His wife Ada Furniss (see MMC/2/Furniss) was also a Manchester doctor.