Fire alarm
Some examples of companies which make fire alarms are Wheelock, Simplex, Edwards, Gentex, Johnson Controls, Fire-Lite, and Notifier (Fire-Lite and Notifier both being owned by Honeywell). There is also Fulleon who are best known for their Roshni electronic sounder. These sounders are often used around Europe and they have 32 user selectable tones.  Sometimes, old-fashioned fire alarms are metal bells. Many fire alarm systems also have flashing lights, also known as strobes. These are important for deaf people who cannot hear the fire alarm. There are also special alarms which are less loud for sleeping areas, so that people are not startled, and white fire alarms for dark walls. In larger buildings, There are 2-step systems with a recorded message, which start off by stating the emergency and waiting for the security guards to be sure there is a fire, then asking for the occupants of the building to calmly evacuate. In smaller areas, there is an immediate alarm, without voice.