Are All Smoke Detectors Alike?

Most people assume a smoke detector is a smoke detector…this is not true.

In the mid 1970’s less than 10% of homes had a smoke detector; now over 90% do. Nevertheless, this dramatic increase in smoke detectors has had little impact on the risk of death by fire. Why? Some studies have indicated that many smoke detectors are either inoperable or have been disabled. Nuisance alarm activations are a major reason why detectors are disabled. National Fire Protection Association, NFPA, studies have indicated ionization alarms account for over 95% of all nuisance alarms.

Another reason is the age of the smoke detector. All smoke detectors should be replaced every 10 years.

What are the statistics on ionization vs. photoelectric smoke detectors?

62-1The majority of residential fire fatalities are due to smoke inhalation. Ionization detectors respond an average of 15 to 50 minutes slower than photoelectric. Some studies indicate they completely fail to work 25% of the time. However, ionization detectors respond faster in fast flame fires. Studies show 30 to 90 minutes quicker than photoelectric. Certainly, either smoke detector is better than none at all. Of course, a functioning smoke detector is most important. But if time and reliability are vital to our chances of surviving a smoldering fire, a photoelectric smoke detector is the best type to install in your home.

Less than 10% of all smoke detectors in homes are photoelectric.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Faulty Smoke Detectors

In a fire, the issue is time.

Minutes and many times seconds will make the difference between life and death. The combustible materials in our homes are different from the past and the technologies of smoke detectors have also changed. There are two types of smoke alarms, ionization and photoelectric. 90% of homes have ionization smoke detectors installed; about 5% are photoelectric and the rest have no alarm at all. The type of smoke alarm can be the difference between your family getting out of the house in time or not.

To better understand the importance of this; there are two types of residential fires, ‘fast flame and smoldering’. The vast majority of residential fire fatalities are due to smoke inhalation from a smoldering fire. And almost two-thirds of these fatalities occur at night while the occupants are sleeping. Photoelectric smoke detectors are by far the best for smoldering fires. Ionization detectors are very slow to respond to smoldering fires. Actually, Ionization detectors have proven to be significantly less reliable in both ‘fast flame and smoldering’ fires.

61-1What type of smoke detectors do you have in your home?

Daylight saving time is a great time to change the batteries in your smoke detectors. This year you should also examine the label on the back of your detectors. If the label says anything about radioactive material, Americium 241, or model number has an “I” then it is ionization. You should replace these detectors with photoelectric. More facts will be in next week’s blog.

All smoke detectors are not alike. Make sure you are protecting your family with the best fire alarm possible.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Aluminum Wiring = Trouble

Because of the high cost of copper, electricians began using aluminum wiring between 1968 and 1974.

Determining that a house is wired with aluminum is not as easy as it may seem. You might start with determining if the electrical panel was installed during the period in which solid aluminum wiring could have potentially been used. After that only a seasoned home inspector or a certified electrician should check to see if the wiring actually is solid aluminum and if that wire has caused heat damage.

To start, you must look at the cut end of the wire to determine if it is a solid or coated wire. Silver wiring is not necessarily aluminum.  It could be copper wire with a tin coating. Similarly, copper wire may not be what it seems. Aluminum wiring was sometimes coated with copper to prevent a chemical reaction between the aluminum wire and its mounting hardware.

The main concern is aluminum wire alloys, produced in the period 1964 to 1981, expanded more than copper wire when they got hot and shrank more when they got cold. This continual expansion and contraction caused loose connections, overheating and eventually house fires.

What should I do if my house has aluminum wiring?

The best solution is to completely rewire the home. This can be very expensive, so there is a code approved alternative. Copper pigtails (a short copper wire) can be connected to the aluminum wires, creating a bond between the approved devices and the wire. This bond will stay secure and prevent overheating.

There are two devices approved to bond the copper pigtails to the aluminum wire. The best is a COPALUM connection which is a form of cold welding and can only be performed by a trained and certified electrician using specialized tools. This is a very costly process. The next best is AlumiCon connectors which are a newer, simpler and less costly alternative, to COPALUM. These devices also must be installed by a licensed electrician.  Amateur installation of AlumiCon connectors is not approved because improper bonding of the wire to the connector can cause serious overheating.

Never let anyone attempt to connect the copper pigtails to aluminum wire with a wire nut. This method has been extensively used in the past. It will absolutely cause overheating and maybe a house fire!  

Aluminum wiring is an issue that should be addressed immediately. Start by calling an ACI Certified Home Inspector for analysis.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI Certified Inspector, ACI
Kaplan University, Home Inspection Lead Instructor

‘Pops’ Rob Leslie
Kaplan Professionals, Retired


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4 Top Tips to Keep You & Your Home Safe for the Holidays

What is the #1 cause of house fire?

The answer is electrical wiring. During the holiday season wiring to Christmas lights and trees are particularly dangerous. Some tips to keep you safe are:

  1. Carefully inspect light strings each year and discard any with frayed cords, cracked lamp holders, or loose connections.
  2. When replacing bulbs unplug the light string and match voltage and wattage to the original bulb.
  3. For exterior lights use only those rated for exterior use.
  4. Both interior and exterior lights should have an Underwriters’ Laboratory label.
  5. When connecting multiple strings of lights check how many can be safely strung together according to the manufacturers specifications or UL listing.
  6. When hanging outdoors lights keep electrical connectors off the ground and away from metal gutters and overhangs.
  7. Never connect more than one extension cord together. Don’t use extension cords that are too long. Never install an extension cord under a rug or near a heat source.
  8. Make sure each outlet you plug into is not overloaded.
  9. Always turn off lights when you leave the house or going to bed.

What is the #2 fire hazard?

Over 40% of all home fires are caused by defective heating equipment. If you haven’t already, you should schedule a tune up and safety check of the water heater, furnace or boiler before Christmas. Be sure the heat exchanger, the vent and flue are inspected. These are the primary causes of fire or CO poisoning.

Don’t forget to inspect both gas and wood burning fireplaces for condition and safe operation. Use a screen or glass door and never leave any fireplace unattended. Don’t burn gift wrappings, tissue, or evergreens in the fireplace.

#3 Keep your Christmas tree away from the fireplace, keep water in the base, and turn off the lights when you leave the home unattended.

#4 Check your smoke and carbon monoxide detectors.

Enjoy this very special season!

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

Can I Use An AFCI In The Place Of A GFCI?

Not if you want to stay healthy!

Both units, although very different in function, look alike in the electrical panel. They look like conventional circuit breakers with a test button on their face and they both attach to the panel in a normal circuit breaker slot and are bonded to the neutral bus bar with a, rear mounted, tightly coiled white wire.

The AFCI, Arc Fault Circuit Interrupter, was introduced to residential electrical codes in 1999 with the requirement to install them in bedrooms and has quickly gained acceptance, particularly with Fire Marshalls, because the device reliably opens damaged circuits that are overheating because of arcing (mini fires). Recent editions of the electrical codes have included installation in most living areas. Unfortunately, there are other over-heating issues with circuits that cannot be detected by the AFCI, such as an electric motor starting or someone pulling a cord out of a live outlet or wires overheating through high current demand meeting high resistance without any arcing occurring.

When must I install these devices?

Never! Installing these critical devices is a job for a licensed electrician. They can advise you as to the necessity for installation of these devices and proper wiring technique. Except for a room addition or replacement of an existing failed device, AFCI’s are usually only installed in new wiring systems.

Where does today’s code require these devices to be installed?

AFCI’s are installed in all bedrooms and living areas, but not unfinished basements and garages. GFCI’s are installed in all potentially wet areas, including kitchens, bathrooms, basements, and exterior outlets. Some circuits can even require the installation of both an AFCI and a GFCI.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired

AFCI or GFCI That Is The Question

Is an AFCI the same as a GFCI and what is a GFI?

AFCI or Arc Fault Circuit Interrupter and GFCI or Ground Fault Circuit Interrupter are names for similar looking electrical devices that are used for very different purposes.

  • An AFCI protects an electrical circuit against a specific kind of arcing. It’ function is to prevent overheating and fire because of damaged or broken wires, loose screws and wire connections. It does this by disconnecting the circuit breaker or fuse before the arc creates a fire.
  • A GFCI is very different. It measures current flow over the hot and neutral wires in circuit acting like an off switch if the amount of current in the 2 wires is not in balance. The assumption is the imbalance is caused by current flowing through you rather than the circuit.  Not a good situation because you essentially become the light bulb.

A GFI or Ground Fault Interrupter is what we used to call a GFCI. The electrical code simply changed the term to make it more precise.

In short, 
The AFCI protects your home from fires caused by wires that overheat through arcing.  The GFCI protects you from being electrocuted by current rushing through your body as it takes the path of least resistance to ground. The GFI only makes electricity more confusing to understand than it already is.

These devices save lives…your home is calling out for these improvements.

Doug Hastings
MN Home Inspector, Minneapolis & St. Paul
ASHI certified inspector, ACI
Kaplan University, Home Inspection Lead Instructor

Rob ‘Pops’ Leslie
Kaplan Professionals, Retired