Detector Tests

Testing smoke detectors is an important part of all fire prevention and life safety plans. Here is a provocative point of view and some industry dialog concerning the view. The opinions expressed here are not necessarily the views of the editors of SECURITY and SDM on the Web. We present this material as a way to challenge current thinking and encourage a positive discussion on this topic. -- Editors

POINT OF VIEW

Testing Home Smoke Detectors: Are Test Buttons A Good Test?

By Leon Cooper

INTRODUCTION

It is important to examine the reliability of test buttons on smoke detectors in the light of some recent studies. The federal government made some significant findings in this connection about residential smoke detectors in two recent studies. ("Smoke Detector Operability Survey - Report on Findings," October, 1994 U.S. Consumer Product Safety Commission. "Fire Incident Study - National Smoke Detector Project," January, 1995 U.S. Consumer Product Safety Commission). In addition to the reliability question, it is necessary to address certain practical problems that make it difficult, even impossible, to use the test button.

A COURT ROOM TEST

Perhaps a good way of getting some visibility on the reliability question is to offer the following court room transcript of an attorney interrogating the CEO of a smoke detector manufacturer. In this case, the attorney is serving as counsel for the estate of the Smith family, all of whose members died during a home fire; the CEO's company manufactured the smoke detectors installed in the Smith household.

ATTORNEY: Please identify yourself for the record.

CEO: I am Harold Jones, Chief Executive Office, XYZ Company.

ATTORNEY: Were there XYZ smoke detectors on the premises of the Smith home?

CEO: Yes.

ATTORNEY: Did these smoke detectors give the Smith family the "early warning" regarding a fire that your company claims?

CEO: Yes, they're designed to do exactly that.

ATTORNEY: Why, then, did all members of the family perish? Do you want to stand by your previous answer?

CEO: Well, I don't know for a fact that the detectors did go into alarm.

ATTORNEY: So you don't really know whether any of your smoke detectors will sound the alarm in the event of a fire?

CEO: On the contrary, we instruct our customers to test their smoke detectors frequently.

ATTORNEY: How are these instructions communicated to the customer?

CEO: Each smoke detector package includes a user's manual which tells the customer how to test the smoke detector.

ATTORNEY: Please read for the record the section dealing with testing.

CEO: (reading) "For a complete weekly test of your smoke detector, firmly press the test button on the cover for a few seconds. The smoke detector will then make a loud continuous beeping sound if it is operating properly."

ATTORNEY: With the court's permission, we introduce as evidence the document just read by Mr. Jones.

(Then, turning to the CEO) Do you recommend any other test?

CEO: No.

ATTORNEY: Let's be sure we understand you. You're saying there's only one acceptable test for making sure the smoke detector works, and that's by using the test button. Is that correct?

CEO: Yes.

ATTORNEY: With the court's permission, I hereby introduce into evidence a report entitled, "Fire Incident Study - National Smoke Detector Project," U.S. Consumer Product Safety Commission, January, 1995. I read from that a section of that report (on page 14) dealing with "Detectors That Should Have Alarmed." "Eight percent (of the detectors that should have alarmed, but did not) were clogged with dust/dirt, and 5% showed signs of insect infestation."

ATTORNEY: (Continuing with the witness) Mr. Jones, please answer this question: Will smoke enter the sensing chamber under the conditions just cited, that is, those with the clogging dust/dirt and insect infestation?

CEO: Probably not.

ATTORNEY: You can be more positive than "probably," can you not?

CEO: Yes, smoke would not enter the sensing chamber of detectors whose sensors were clogged with dust, dirt or insects.

ATTORNEY: Please listen carefully to this statement, Mr. Jones: That means, then, that even though pressing the test button causes the alarm to sound, it still doesn't mean that the alarm would sound as a result of smoke being introduced to the sensing chamber. Is that correct, Mr. Jones?

CEO: Correct.

ATTORNEY: In other words, based on your testimony, it seems clear that the test button is not a reliable functional test. And those customers who rely solely upon the test button do so at their peril, do they not? And if the Smith family tested your smoke detector in the manner recommended in your user's manual and heard the horn, they assumed -- with fatal consequences -- that the detector was okay. Is that not true?

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PRODUCT LIABILITY

We will leave our squirming CEO at this point, allowing the reader to arrive at his own conclusions regarding the CEO's answer to the attorney's last group of questions and, of course, the jury's verdict.

The foregoing is not the writer's flight of fancy. Given the many residential fires that occur daily, it is likely that cases involving death and injury resulting from home fires have already been heard in the courts. An attorney knowledgeable about smoke detectors can certainly press his case as vigorously and as effectively as has been outlined above. (Possibly, such an attorney is now reading this article, gathering the insights required to win substantial damages for his client.) In any case, the liability exposure to smoke detector manufacturers should be obvious.

SIXTEEN MILLION SMOKE DETECTORS DON'T WORK -- SO SAYS THE FEDERAL GOVERNMENT (Op.cit. "Smoke Detector Operability Survey," (p.ii).

That means that more than one of every five homes in the U.S. have smoke detectors that won't work in the event of fire. This should be a loud wake-up call to detector manufacturers (and to the merchandisers who sell their detectors). The government "Operability Survey" findings make it abundantly clear that the test button test does not offer assurance that the detector will always respond to a fire. This is why the federal investigators used a manufactured aerosol product to round out the testing procedure.

The test button question also explains why at least one smoke detector manufacturer recommends that actual smoke be used in addition to the test button. This is a left-handed acknowledgment that this particular manufacturer lacks confidence in the test button in his detectors -- even though one may question the wisdom of encouraging customers to start fires every week in their homes in order to test the detectors, not to dwell upon the consequences of flooding the home's living quarters as well as the smoke detector with a pollutant that is most likely toxic.

OTHER PROBLEMS WITH TEST BUTTONS

NFPA and others who emphasize the test button test should also recognize other serious problems regarding the test button. Unless the homemaker is a professional basketball player, he/she must stand on a chair or some type of elevation in order to reach the test button, assuming the detector is located at normal ceiling height, eight feet. Add to this our increasingly "graying population," such individuals are reluctant, naturally, to stand on a chair, risking life and limb. In many instances, the homemaker is physically incapable of doing so. By the same token, telling the homemaker to press the test button ignores the fact that there are several million smoke detectors in U.S. homes without test buttons, that is, 3% of all homes with smoke detectors, according to the government reports discussed here.

Some have suggested that smoke detectors can be tested with a broomstick, this in lieu of climbing on a chair to press the test button. Repeated jabbing of the test button with this clumsy object will soon force displacement of the test button from its contacts or otherwise damage it. Further, the test button recess in a number of detectors has a diameter smaller than that of a broomstick, effectively preventing the button from being depressed by this means. Finally, it is literally impossible in a number of cases to use a broomstick to press the test button on wall-mounted units.

It is of critical importance to address the question: Do homemakers regularly test their detectors? Given the many obstacles to the householder that stand in the way of the testing procedure, it should come as no surprise why so many smoke detectors don't work, i.e., haven't been tested, as the government survey found.


ACTION PROGRAM

Clearly, smoke detector manufacturers must take action now to deal with the test button problem (and their merchandisers must insist that they do so), all with the objective of reducing the number of faulty detectors in U.S. homes. Among other actions to be taken:

Make it easy -- and with more assurance and thoroughness -- for homemakers to test their detectors by encouraging, or at least authorizing, the use of a manufactured aerosol product that has been approved for testing smoke detectors by a recognized independent testing laboratory. (NFPA Standard 72E sanctions the use of such a testing device.)

Phase out the production of residential ionization-type smoke detectors because (a) this type of detector is the one most frequently cited by the government investigators as prone to nuisance alarms, causing the user to remove the power source or otherwise disable it. Further, fire safety specialists typically recommend the photoelectric type for the home because of its superior ability to sense the cold, smoldering smoke that attends the most deadly type of home fire; (b) the radioactive material in ionization detectors is Americium 241, a by-product in the manufacture of Plutonium. This radioactive isotope simply aggravates the already serious problems we in the U.S. and, indeed, the world, face in disposing of radioactive materials. There are tens of millions of ionization-type smoke detectors in U.S. homes, and more are being added daily.

Manufacture and sell only photoelectric detectors for the home, preferably the AC type with battery back-up.

Overhaul and rewrite the users manuals that come in the detector package. A review of these manuals reveals a dismal landscape of obtuse verbiage regarding detector installation and maintenance. They seem to be written more as an after thought rather than as a document to be read carefully by the user. As this writer reads the typical manual, he is reminded of the manuals that came with the early PCs, burdened with jargon and obfuscation, written by programmers for other programmers. Surely, it is not too much to ask that manuals be written with the householder clearly in mind -- on quality paper, with plenty of graphics. Well written manuals will greatly aid in proper installation and testing.

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CONCLUSION

The following data show results of the federal investigation of "Fire Incident Study-National Smoke Detector Project" (Op. cit., "Smoke Detector Operability Survey" p.24).

Worked when Power was Restored

Did Not Work

Unable to Test

Worked

This data show clearly how serious the problem is ... more than one in every two smoke detectors would not warn the home occupant of a fire.

There has been a reduction in fire deaths and injuries in the home resulting from the widespread use of smoke detectors. Currently, 4,000 deaths and 22,000 injuries annually are directly related to home fires, contrasted with the many thousands more of deaths and injuries that were experienced before smoke detectors came into common usage. Even so, the U.S. still ranks among the highest in home fire casualties among the industrialized nations of the world.

It has been estimated that smoke detectors reduce the risk of dying by 50% -- but only, this writer adds, if the smoke detectors are working properly. The federal survey and other studies have revealed a crowning irony: "More than an estimated 11 million households in 1992 had no smoke detectors installed, and an even greater number, about 16 million households, had detectors, but none were working." (Op. cit., "Smoke Detector Operability Survey," p.24). This leads to the tragic conclusion that fire deaths in homes with smoke detectors were half as many as occurred in homes without smoke detectors at all. A logical assumption would be that most, if not all, detectors failed to give the early warning. And, as we have seen, there are practical -- even insurmountable -- difficulties in using the test button, i.e., among the aged and infirm.

There should be no doubt that more, dramatic progress can be made in reducing home fire casualties in direct proportion to increasing the number of working smoke detectors. And this can best be achieved by making it easier to more thoroughly test these devices, namely, by encouraging homemakers to use a manufactured aerosol product that has been approved by a recognized independent testing lab as suitable for testing detectors.

Smoke detector manufacturers of residential smoke detectors should be more sensitive to the ever-mounting problem of disposing of radioactive materials by phasing out the manufacture of single station ionization-type detectors. Manufacturers should concentrate their efforts instead on the production of photoelectric devices for the home, thereby materially reducing the nuisance alarm problem attendant upon the use of ionization types.

Like any electronic device, smoke detectors have a limited life span. After several years in use, "drift," corrosion, or other problems begin to develop, causing the detector to alarm too soon, too late, or not at all in response to the fire signals which attend the fire's onset. The problem is aggravated over time, of course. (One estimate has been that a smoke detector in operation for 10 years has gone through 3.5 million monitoring cycles.) Owners of aging detectors should be encouraged to buy new ones, replacing these unreliable devices. Smoke detector manufacturers and NFPA can aid in this replacement program by mounting an educational campaign directed toward informing the public that smoke detectors do "wear out." Manufacturers can materially aid in the replacement effort by offering a "trade-in" discount.

As the nation's policy-making body, Congress should be mindful of the need for at least a Joint House Senate Resolution calling for the regular testing of smoke detectors.

Finally, it would be very much in the interest of fire departments, insurance companies and others concerned with fire safety to aggressively assist in implementing the fire safety improvements given here.

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