Not ALL CO Alarms, or CO Standards Are Created Equal

by:  George E. Kerr,  October 01, 2000

In these days of Growing LIABILITY CONCERNS and Huge Court judgments, it is more Critical than ever that HVAC Contractors, Utility Companies, and Home Builders more fully  Understand  what vast differences exist in seemingly “SIMILAR” products, and the “Approval, or  Listing” Standards to which they are manufactured.

First, it should be pointed out that Most [not all] Carbon Monoxide Alarm manufacturers design into their products ONLY the degree of Quality and Perfection that is REQUIRED by the “Listing” or Testing Laboratory whose Certification they are seeking.


In North America, we normally have to Consider only UL and CSA Listings; therefore, let’s review the  “VITAL DIFFERENCES” in CO Alarms which Display these “Listing Label”; as well as the testing levels, ………. WHICH ARE EXACTLY THE SAME  ! ! !

Therefore, a Comparison is far less difficult than one might think, BECAUSE, ALMOST  EVERYTHING is EXACTLY the SAME at the Time of Initial Testing. Both UL-2034-98, and CSA-6.19 – 99, REQUIRE that a CO Alarm sound a Warning at, or before, a “Time-Weighted” average of CO exposure that would create a COHb level of 10% in the human blood stream.


The actual “Test Points”, that they Claim reflect this requirement are:

70 ppm … within 240 Minutes [ but NOT within the first 60 minutes]

150 ppm within 50 Minutes     [ but NOT within the first 10 minutes]

400 ppm within 15 Minutes     [ but NOT within the first 4 minutes]


Therefore, BOTH Standards REQUIRE Alarm Activation, at or before, these Time Frames. ………… So what’s the “BIG DEAL”, … about the “BIG DIFFERENCE” in APPROVAL STANDARDS” … you say ? …………… The Big Difference is HUGE ! ! !


To obtain a “Listing & Label” from UL since the Very First Day of UL-2034, on April 30, 1992, … up to and including UL-2034, Oct. 01, 1998 Edition, a manufacturer could build [10,000 – 20,000, etc,]  to “Hand-Pick” the Very Best 36 or so, of these CO Alarms to send in for various testing procedures. UL would normally choose 12 of these samples for the true “Test Samples”.

If this SMALL SAMPLE passes all of the Required Tests, the Manufacturer could then proceed to produce 100 Million or More CO Alarms ….. without ANY further Required Testing, … as long as NO PRIMARY COMPONENTS ARE CHANGED.

Also of VITAL IMPORTANCE is that UL permits the Manufacturer to “CLAIM” … ANY … “Lifetime”, … or “GUARANTEED” period they CHOOSE, …..  NO TESTING, or Proof of Performance REQUIRED.

PROOF  POSITIVE that the “Lack” of a REQUIREMENT to Monitor the Sensors in CO Alarms for Continued “Lifetime” Performance, has become VERY MUCH a matter of Public Knowledge recently, as a RESULT of the CPSC RECALL of a MILLION

Kidde-Nighthawk CO Alarms. [ 650,000  CO Alarms & 350,000  “Life-Saver”  CO Detectors]


Another VERY Strong Indication of the NECESSITY for Better Quality Control Requirements can be found in the Recent Release, AFTER MUCH DELAY, of the INTERNAL testing done by UL on NEW, Un-Opened C O Alarms which they re-purchased from Retail Stores in the Chicago Area.

This Testing Revealed the following “STARTLING” facts:


46.3% FAILED at Least one REQUIRED TEST.

17.7% had NO RESPONSE at 20% COHb.     [RESPONSE at 10% is REQUIRED]

70ppm  Test   =  53.7  FAILED [Required test]

150ppm  Test  =  47.2%  FAILED [Required test]

400ppm  Test  =  29.7%   FAILED [Required test]


If you FEEL SAFE, SECURE, and PROTECTED,  from  CO Poisoning LIABILITY, as well as Personal Danger, ….. with this type of Product Performance, and Quality Control Production Processes, ….. you can STOP READING RIGHT NOW, …if NOT, …..  CONTINUE   ! ! !

CSA – 6.19 – 99 … on the other hand DOES REQUIRED … not ONLY “Time of manufacture testing, but FAR MORE IMPORTANT, CSA also REQUIRES full “LIFE-TIME” Compliance Testing. …..  What does this really mean to the Consumer,….. well let’s Evaluate Two Scenarios.

A UL Listed Manufacturer can say: “Well, the Consumer is more likely to buy our C O Alarm if we say that it is GUARANTEED for 5, 6, or even 10 Years, and since we Require “Proof of Purchase” to Honor our Guarantee, and KNOW that most people will NOT KEEP a receipt on such a low cost purchase, … well, what the Heck, “we will just take our chances”. “After all, we Don’t have to do any additional Testing, or PROVE our Claims; therefore, our Costs will stay about the SAME, and our Sales will be Greatly Increased, ….. SURE, let’s say 5, 6 or 10 Years, ….. so What”.

A CSA LISTED Manufacturer in the SAME Situation KNOWS GOING INTO such a decision making process that:…  “I HAVE TO PROVE WHAT I CLAIM IS TRUE”  ! ! !

“If I Claim that this CO Alarm has a 5 year LIFE-TIME, I realize that means that even if I am only producing 10,000 CO Alarms a Quarter, that I MUST TEST at LEAST 230 Units a Quarter, … EVERY QUARTER, … after EVERY QUARTER, … REPEATEDLY for 5 FULL YEARS, … meaning that our First Quarter’s 230 Samples … MUST BE RE-TESTED … 20 TIMES, … over that 5 YEAR DECLARED “LIFE-TIME”.

This is “IF”, … EVERY SAMPLE is PERFECT; however, … “IF”, for Example the “Time of Manufacture” ….. “FAILURE RATE” … is .88 percent, … [less than the 1% “Shut Down” Rate], … the REQUIRED “SAMPLE SIZE”, if Total Production is 100,000 units, would be … 11,406 “Sample”  CO Alarms, … to be Pulled out of Production, [can NOT BE SOLD], … and MUST BE “RE-TESTED” … EVERY 90 Days, … [20 Times], … over the 5 Years “DECLARED” …”LIFE-TIME”.

“This is not only a LOT of TIME & TROUBLE, ….. IT IS A HUGE EXPENSE, … am I SURE that I want to really CLAIM a 5 Year “LIFE-TIME”. …. and am I WILLING to “PUT MY MONEY”, ….. where my CLAIMS ARE “ ? ? ?

The DIFFERENCE, ….. is HUGE, ….. make SURE that EVERY UL Listed CO Alarm in your Home,  is Also Listed to CSA – 6.19 – 99, or a Later Version.


It  is  YOUR  LIFE, ….. BE  SURE, ….. BE  SAFE, ….. it  IS  up  to  YOU  ! ! !


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CO Experts
19299 Katrina Lane – Eldridge Missouri 65463-9102
Tel: 1-888-443-5377 Fax: 1-888-436-5377