Pat Johnson joined the Bankstown SES in 1975 from a nursing background in the RAAF. She was motivated by the events of Cyclone Tracy and by a desire to utilise her management skills which were not being fully used. Asked to be a member of the Welfare Service, Pat complied but she did every course available - rescue, first aid, communications and floodboat operation - and went twice to Mount Macedon to study operational response management before becoming the Deputy Controller of the Bankstown unit in 1979.

In 1982, Sydney Southern Division Controller John Jeppesen encouraged Pat to join the SES's Nursing Reserve, a group to which many ex-nurses belonged at the time. Another was Helen Halpin, later the Oxley Media Officer, who like Pat became frustrated when the reserve was never used in hospitals or in the field during emergencies. The reserve was disbanded in the mid-1980s, by which time Pat had found a niche in operations management. Her speciality in recent times, during which she has been Deputy Controller of the Sydney Southern Region, has been managing out-of-area assistance task forces for operations such as the Thredbo Landslide response and numerous bushfire support operations. She also manages logistics.

In 2000 Pat played a major role in organising the SES contribution to the Sydney Olympic Games, and more recently she travelled all over the state as a nurse immuniser administering hep-B shots to more than 3000 volunteers. She has also been the editor of the magazine of the Volunteer's Association The Volunteer and is widely regarded as the 'mum' of SES mascot Paddy Platypus.

Pat won a Year of the Volunteer scholarship in 2001 to visit Japan to study emergency management arrangements in that country, and in the same year received a Director General's Commendation. Three years later she was awarded the Emergency Services Medal for the breadth and depth of her committment to the SES.