558 E. Industrial Place

Palm Springs, CA 92264

2823 Camino Del Mar

Del Mar, CA 92014

}

Available 24/7

For All Emergency Calls

Call Day or Night

(760) 322-0995

How Do Ionization Smoke Detectors Work?

by | Jan 20, 2021 | FAQs | 0 comments

 

A smoke detector is a small device that often goes unnoticed, until it is set off! In this article you will learn how smoke detectors work to keep us safe from potential fire disasters. 

Basic Components Of A Smoke Detector

Did you know there are two types of smoke detectors? All smoke detectors consist of two basic parts: a sensor to sense the smoke and a very loud electronic horn to wake people up. Smoke detectors can run off of a 9-volt battery or 120-volt house current.

Ionization smoke detectors use an ionization chamber and a source of ionizing radiation to detect smoke. This type of smoke detector is more common because it is inexpensive and better at detecting the smaller amounts of smoke produced by flaming fires.

 

The Science Of An Ionization Smoke Detector

Inside an ionization detector is a small amount (perhaps 1/5000th of a gram) of americium-241. The radioactive element americium has a half-life of 432 years, and is a good source of alpha particles.

Another way to talk about the amount of americium in the detector is to say that a typical detector contains 0.9 microcurie of americium-241. A curie is a unit of measure for nuclear material.

If you are holding a curie of something in your hand, you are holding an amount of material that undergoes 37,000,000,000 nuclear transformations per second.

Generally, that means that 37 billion atoms in the sample are decaying and emitting a particle of nuclear radiation (such as an alpha particle) per second.

One gram of of the element radium generates approximately 1 curie of activity (Marie Curie, the woman after whom the curie is named, did much of her research using radium).

An ionization chamber in a smoke detector is very simple. It consists of two plates with a voltage across them, along with a radioactive source of ionizing radiation, like this:

The alpha particles generated by the americium have the following property: They ionize the oxygen and nitrogen atoms of the air in the chamber.

To “ionize” means to knock an electron off of an atom. When you knock an electron off of an atom, you end up with a free electron (with a negative charge) and an atom missing one electron (with a positive charge).

The negative electron is attracted to the plate with a positive voltage, and the positive atom is attracted to the plate with a negative voltage (opposites attract, just like with magnets).

The electronics in the smoke detector sense the small amount of electrical current that these electrons and ions moving toward the plates represent.

When smoke enters the ionization chamber, it disrupts this current — the smoke particles attach to the ions and neutralize them. The smoke detector senses the drop in current between the plates and sets off the horn.

Speaking of alarms, whenever the words “nuclear radiation” are used an alarm usually goes off in many people’s minds.

But the amount of radiation in a smoke detector is extremely small. It is also predominantly alpha radiation. Alpha radiation cannot penetrate a sheet of paper, and it is blocked by several centimeters of air.

The americium in the smoke detector could only pose a danger if you were to inhale it. Therefore, you do not want to be playing with the americium in a smoke detector, poking at it, or disturbing it in any way, because you don’t want it to become airborne. 

This is another reason to always respect smoke detectors, no matter how annoying they can be. 

Now you know about the ionization smoke detector, you can learn about the second kind of smoke detector, the photoelectric smoke detector

Learn more about fire safety equipment

Find valuable life saving answers to frequently asked questions about fire protection and preparedness on our F.A.Q page.

professional behavior workplace essay go to site watch term paper blessing by anna quindlen viagra and duration of erection https://goodbelly.com/rxpack/prezzi-in-farmacia-del-cialis/32/ https://shepherdstown.info/conclusion/narrative-essay-on-volunteering/17/ citrate de sildenafil 100mg rebecca daphne du maurier essay source url https://www.nationalautismcenter.org/letter/examples-of-how-to-write-an-essay-for-college/26/ https://tffa.org/businessplan/dissertation-hand-in-instagram-captions/70/ parchment paper for writing go site stopping cymbalta withdrawl symptoms is propecia safe 2012 william faulkner barn burning thesis statements about daca Dangers of Using Expired Viagra essay dante cantos plan for your future essay essay writing scholarships for high school students paper writing service source url follow url see mba essay editing https://www.nationalautismcenter.org/letter/coating-engineer-film-process-resume-thin/26/ see source site words with thesis Do you have a business in San Diego or Coachella Valley area? 

 Contact Desert Fire for the best services in fire extinguishers, fire alarms, fire suppression systems, fire sprinkler tenant improvement, inspections, certifications or ground up systems. 

✔ Free estimates. Just give us a call or send us a message.

✔ We’ll beat anyone’s prices.

✔ 24/7 Emergency Service. Call us anytime!

 

Recent Posts

Fire Safety Laws in Palm Springs

Fire Safety laws and regulations are extremely important to keep up to date. You can find the most recent info on fire safety laws, permits, fire codes, and more on the City of Palm Springs fire prevention website  It's our job to keep customers in the loop on local...

How To Turn Off A Fire Alarm (& end the beeping!)

We’ve all experienced a false alarm from smoke detectors in our homes or fire alarm systems in buildings. Fire alarms and smoke detectors can save lives and they can also be very annoying and difficult to turn off once they’re triggered or have become faulty.  In this...

Fire Extinguisher Placement: All You Need To Know

 What are the NFPA fire extinguisher location requirements?    In this article, we will outline the most important places to keep fire extinguishers in your business or home, as recommended by the NFPA (National Fire Protection Association). The importance of fire...

How Do Multi-Class Dry Chemical Fire Extinguishers Work?

  In this article you will learn about multi-class dry chemical fire extinguishers and how they work, as well as some alternative ways to fight fires.  If you ask any firefighter what it takes to create a fire, you will learn that you have to have three things: A...

Fire Alarm Degrees: What You Should Know

1, 2, 3, 4, 5 ALARM FIRES: WHAT DO THEY MEAN? 1 alarm fire, 2 alarm fire, 3 alarm fire, 4 alarm fire, 5 alarm fire. You’ve probably heard of these different levels of fire alarm emergencies before, but do you actually know what they mean?  In this article, you will...

QUICK LINKS