Questions regarding a competitor’s product

Mr. Kerr,

First Alert gave our Fire Department 300 CO detectors yesterday and it was all over the news.

They are recommending everyone purchase a CO detector and are mandating that day care and nursing and assisted living homes install them in their facilities.

What do you think about the First Alert CO Alarms in these facilities?

I will be forwarding the article you faxed me to the Fire Chief and Training Officers.

Sincerely, Victor


Dear Victor,

Do you know the “Model Number” of the First Alert units given to the Fire Department?

They were “Probably” NON-digital units, which means that they would NOT have to make an “Accuracy of Digital Display” statement, however, on the First alert Model FCD4, “Electric with Battery Backup”, With Digital Display,…. on page #19 of that Owners Manual, they SPECIFY the Temperature, Humidity, and Air Pressure, … and then say “Under these Conditions, the Accuracy of the Digital Display is PLUS 100% …. MINUS 40% !

Also, ANYTIME you are “Discussing” a Nighthawk CO Unit, it is Important to KNOW the DATE of MANUFACTURE ! ! !
IF it was PRIOR to October, 1998, … 99 times out of 100, IT WILL BE A MOS Sensor, …..which offers OVER 2,000 possible “Cross Sensitivity” Possibilities. [Once again I refer you to the GRI Final Report of 1999 / 2,000].

Second, “ROASTING” ANYTHING ORGANIC …… is a Moderate form of “Burning”, which causes Molecular Change, which produces “Fumes, and / or, Gases”, as well as INCREASED HUMIDITY in the Immediate Area.
Therefore, just as a piece of plastic that gets HOT Enough to WARP, produces enough GASES to set off a GAS/CO Detector, ….. ANYTHING that is being “ROASTED” … “COULD” cause CO Readings.

If it involves a MOS Sensor, … the INCREASE of HUMIDITY ALONE can Cause an Increased Reading. Add the factors of the SUPER-SENSITIVITY of MOS Sensors as they “AGE”, … and the “Plugged-UP’ Filters, … and “FALSE”  / “NUISANCE” ALARMS are VIRTUALLY GUARANTEED  ! ! !

In my opinion, the #1 CAUSE of CO Detector/Alarm PROBLEMS, “False / Nuisance” Alarms, … and “False Negatives” [Failure to Alarm when they SHOULD], are a RESULT of HUMIDITY CONDITIONS. BOTH MOS and COLOR METRIC SENSORS are VERY
Obviously, the “FAILURE to ALARM” in LOW HUMIDITY Conditions is a FAR GREATER PROBLEM, … and has PROVEN to be TRUE with both of the MOS and Color Metric Sensors used in CO Detectors / Alarms.

Add these Facts to the Manufacturer’s OWN STATEMENTS, such as:

First Alert Model FCD4, on page #19 of its Owner’s Manual states: “DISPLAY ACCURACY”: “Accuracy is +100% -40% of actual concentration of CO at 50%RH+/-5%RH and 73F+/-4F [23+/-2C].

ALL Nighthawk MOS Sensor Products using the MOS Sensor Technology State that they are Accurate: Plus, or Minus 40%, PLUS 15 PPM [parts per million].
Most of these units were Manufactured prior to Oct. 1998; however, Many have been purchased since that date, … and Millions upon Millions are STILL in use throughout the World.
In October, 1998, Kidde/Nighthawk introduced their Version of an Electrochemical Sensor, [not the “Industrial”, Acid Based, used in Professional Instruments], and was Promptly faced with a Million Unit [1,000,000] RECALL, with 650,000 of these being their NEW SENSOR, and 350,000 being their “LifeSaver” Brand, Color Metric SENSORS.

The PRESENT Nighthawk CO Alarm Owner’s Manual on their Top of the Line, Electric with battery Backup Units State that the Digital Display is Accurate: Plus, or Minus 20% plus 15 PPM; however, NOT at Low Levels or on peak recall, and under Specific Conditions, with an Un-Contaminated Sensor.

All  UL-2034/CSA-6.19 Listed CO Alarms Packaging has the following, or Very Similar Warning:
It is NOT designed to measure CO Levels in compliance with Occupational Safety and Health Administration [OSHA] commercial or industrial standards. Also that many individuals need to seek a DIFFERENT DEVICE.

Nighthawk’s actual statement is:

“Pregnant women, infants, children, senior citizens, persons with heart or respiratory problems, and smokers may experience symptoms at lower levels of exposure than noted. Individuals with medical problems may consider using warning devices which provide audible and visual signals for carbon monoxide concentrations under 30 ppm.”
GRI “Testing” indicates that with “Changes in Humidity”, these units are “Off ” as much as 300% or more.

The Pregnant, Infants, Young Children, the Elderly, as well as those who are Sickly, or Infirm … are the VERY ONES that NEED the Chronic Low Level CO “Health” Protection provided by my CO-Experts Low Level CO “Health” Monitor.

A First Alert type CO Alarm being used to provide CHRONIC Low Level CO Poisoning Protection for these people, would be a SAD, SAD “JOKE” !!!

“A FALSE “Feeling of Security”, …. is WORSE than NO FEELING of SECURITY AT ALL !!!

(Also, remember that ANYTIME you see a CO Unit that says CO “Detector” on it, … that AUTOMATICALLY tells your that it was manufactured  BEFORE October 1, 1998 !!!)

Regards, George



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