the purple pinkish thats like a helpful shield?
Batteries are bad replace them or get new ones, I had one that wouldn't stop so I put it outside but one morning it went off and I thought it was the neighbors and woke them up but later to my dismay I found it was the one I put outside in a box so I took a hammer to it and still had to beat it to death until it stopped. Now I just replace them every year-the whole thing. I never told the neighbor it was my smoke detector as neither one of us could figure out where the alarm was coming from and I woke him up pretty early. If I was still living there I would tell him and I'm sure it would give him a laugh, not so that morning. Some of them are disposable or have backup batteries when they are hard wired in and if they go bad the are hard to shut them up!
In a nuclear weapon the mass is encased in lead so there is no radiation hazard.
they only good for so long once a couple start going off like that replace them all you can get them at electrical supply house builders model about $10 each if you start changing 1 at a time you loose track of what you changed out and reoccurring problem
If the detectors are very old the sensing elements can start to fail and you have to renew the whole thing. They are not expensive, if playing up I suggest you renew.
I had same problem they would go off early hours of the morning radomly and frighten the life out of me. I changed the batteries twice - still kept doing it. I wrote to the company and they sent me a pair of brand new ones that were better quality - I was well pleased. Give it a try.
