It is also compatible with Doro's automated care centre, i-care, for which the company charges a 48-euro (£40, $52) subscription per year.
I-care enables employers to closely monitor the status of the phone, including battery power and periods of inactivity.
It can also send messages asking if the owner of the phone is all right.
It is designed for people who work on their own - either in hazardous environments or entering others' homes by themselves.
"We don't want to do 'me-too hardware', but to deliver our service on to someone else's [device] is not so easy," said Mr Millington.
"You need a system that's going to take over control of the device."
Until now, Doro had specialised in handsets for older people and it had 130,000 subscribers for its range of "digital telecare solutions", Mr Millington said.
Smartphone expert Ben Wood, from CCS Insight, said Doro was entering a competitive market, already crowded with both rugged devices, such as those offered by construction brands De Walt and Cat, and dedicated care apps.
"It is interesting Doro is making the jump from seniors to lone works, but I can see the synergies - many of the requirements are the same," he said.
"It has a strong position in the 'phones for seniors' market and works with all the main networks in the UK."