As chairperson of the Royal National Institute for the Deaf (RNID) from 1985 to 1992, she led a reform of its management to create clear duties for all the staff.
[3][4] He was married to Edith Wylde (née Addison) and was a descendant of Scottish landowners from Midlothian; Tumim's great-grandfather Thomas Borthwick was appointed a peer but died before the issuing of letters patent in 1915.
[7] In 1974, she became a governor at Mary Hare Grammar School for the Deaf in Newbury and was a member of the Warnock inquiry on the education of handicapped children four years later.
[4][8] Tumim reorganised the management of the RNID to create a clear distinction of responsibilities of her job, the committee and its paid and volunteer staff.
Tumim focused mainly on trustees' attitude and performance and learnt two-thirds of interviewees did not know their legal and professional obligations.
[2] She called this state of management "mad chair disease" in a report emphasising the need to improve the appointment and education of trustees.
[2] Recognising the need to take a more rational approach to teenage pregnancy,[4] the group produced reports to promote awareness of it the and possible routes to lower the rates.
[10] Tumim hosted the Sunday luncheons at St Edmund Hall, Oxford, in the Warden's Lodge,[2] and joined the General Medical Council as an associate member,[1] having been on its disciplinary committee from 1996 to 2003.