Her move is part of a major restructure of corporate comms, which is now shared between the police and fire services.
This is the result of a decision made last year by the then-Home Secretary, Amber Rudd, to allow Staffordshire's police and crime commissioner Matthew Ellis to take additional responsibility for the Fire and Rescue Service.
The controversial move is expected to save £36m over the next decade.
The police and fire services will remain separate entities with their own budgets and staff, according to Ellis.
However, a range of functions will be shared, with staff who join the shared functions from the fire service becoming police employees. The operational parts of both organisations are unaffected.
Commenting on her new role, which started this month, Challinor told PRWeek: "This is an exciting challenge for me as I will be working in a new team that has been brought together to serve both police and fire."
The comms teams from the two organisations were merged in August to form a single structure, developed to support both organisations.
Within this structure there are news, social media, campaigns and engagement, internal communications and digital teams that report to three senior comms managers.
Lisa Benbow, head of corporate comms, Staffordshire Police and Staffordshire Fire and Rescue, commented: "It's been a challenging and exciting few months as we have brought the two teams together to create a new shared communication service for Police and Fire and Rescue."
She added: "Thanks to lots of hard work, energy and enthusiasm from comms colleagues we have already identified some great opportunities to share knowledge, ideas and expertise to develop the services we provide, which is critical at a time when policing and fire and rescue are placing an ever-growing reliance on effective strategic communications."
Estates and facilities, procurement and human resources are also shared functions, and finance will join them as a shared service from next month.
Challinor commented: "Although this is a shared team, our key stakeholders, which include colleagues, partner organisations and, of course, local communities, are unlikely to notice much change as they will continue to receive communications from the separate organisations."
She said: "Obviously we have organisational priorities to meet and some work has been carried over, but it's given us the opportunity to look at everything with a fresh perspective. Each organisation will still have their individual campaigns, but the collaboration will allow us to run shared campaigns much more effectively and efficiently, so there's lots of potential."
Challinor's role is a job-share with Becki Lord, a senior comms manager at Staffordshire Police.
Future campaigns over the coming months include supporting the force's roads policing unit in raising awareness of the dangers of using mobile phones while driving as well as drinking and/or taking drugs and driving.
An electrical fire-safety campaign is currently being developed, to launch in December, to raise awareness of the dangers of second-hand and counterfeit goods. It will tie in with Christmas messaging, as a lot of electrical goods are purchased at that time of year.
A further campaign is being planned for next April, in which young drivers will be targeted with messaging on the risks of speeding, using a phone while driving, not wearing a seatbelt, and drink driving, as well as other key factors that result in collisions involving young drivers.
Click here to subscribe to the FREE public sector bulletin to receive dedicated public sector news, features and comment straight to your inbox.
Make sure you register for the site to access more than one story per month.
To submit a news, comment, case study or analysis idea for the public sector bulletin, email Ian.Griggs@haymarket.com