bald guys, massaging chairs, speed bumps, my phone when it's on vibrate, etc etc
Most smoke alarms have a lifespan. The alarms I just installed last 7 years and will alert you when the 7 years is up and they need to be replaced. I would look into replacing yours if you think they are older. Try to get the same brand/model/style so you can just unplug the old ones and plug in the new ones. You can also buy 10 year lithium backup batteries. They cost a little more upfront but easily save money over the life of the detector. You then no longer need to change the batteries every six months but you should still test them.
Formaldehyde does not exist in nail polish. It is used in some nail hardeners but not in the actual polish. A resin, tosylamide/formaldehyde resin, makes the polish tough and resilient. While the resin is manufactured from formaldehyde, once the product becomes a resin, the formaldehyde is chemically changed and essentially no longer present. So while formaldehyde is grouped in with toluene and DBP in marketing statements and considered one of the Big 3, it isn’t actually an issue unless you have a reaction to the formaldehyde resin. The bottom line, you should be aware of formaldehyde in your treatment products, not polish. So basically, OPI isn't lying. When a company says their polishes are The Big 3-Free, they are. They don't include anything harmful in their polishes, they've completely done away with them. The formaldehyde resin isn't anything important unless you have an allergy to it. I mean, it isn't harmful at all. OPI is safe, no toxic chemicals :) I'll post a link below, and hopefully this information helps you!
If you're talking about safety road signs, I'm guessing red, yellow and orange.
