A seven dollar alarm saved the lives of Masterton mum Ashleigh Bedford and her family, she says, after its screaming woke them in the early morning as their home filled with smoke.
Ms Bedford had bought the alarm about five months ago but thought nothing of the device as she wandered beneath it in the hallway about 6am Wednesday morning, she said.
Asleep in the three-bedroom house were her three-week-old daughter, her toddler Elizabeth and her mother-in-law Ann Brook.
Ms Bedford had wearily stoked their firebox - a frost had fallen outdoors - before checking on her baby and three-year-old toddler, who was exhausted like her mum after a late night vigil at the Wairarapa Hospital emergency rooms.
"She was sick with a cold and got a really bad bleeding nose in the middle of the night. I was worried it was all due to her being sick. I took her to the emergency room and we were at the hospital until about 2.30 that morning. I wouldn't have woken up without that alarm, I was so tired, " Ms Bedford said.
The alarm had failed to at first wake her mother-in-law and Mrs Bedford rushed from room to room to ensure each family member was roused as she went.
"It woke me up first, so I grabbed my toddler and got Ann to grab my baby and get out of the house. There was quite a bit of smoke, a lot of smoke. You couldn't see the ceiling and it was quarter of the way down the walls," she said.
"It hadn't got into the rooms because of where the alarm was in the hall, so we went into my daughter's room to wait for the Fire Service because she couldn't stand the cold outside."
Firefighters arrived to discover the firebox was blocked and had sent smoke billowing back into the home, and an ambulance crew checked and cleared Mrs Bedford, her daughters and mother-in-law for smoke inhalation.
"The smoke alarm did its job pretty quickly and it's very lucky we're all still alive - very, very lucky. That smoke alarm is the best $7 I've ever spent."
Ms Bedford said the chimney had been cleaned later the same day and "everything is good to go now".
"I was getting a bit paranoid and so I went out and got an alarm about five months ago. Now it's saved our lives. It was pretty intense."
Masterton Fire Station Officer Mike Cornford said a chimney blockage was blamed for the incident and he was heartened to know the chimney had been since cleared and cleaned.
Firefighters had established the cause for the smoke and ventilated the house, which had been rapidly filling before emergency services arrived.
He said the smoke detector had proved invaluable and the incident was "a timely reminder", given the weather and season, that homes needed to have working alarms installed.
"The blockage was possibly due to a lack of maintenance, which is another reminder to people at this time of the year, and the smoke alarm was certainly a lifesaver."