[Federal Register Volume 84, Number 160 (Monday, August 19, 2019)]
[Proposed Rules]
[Pages 42847-42854]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-17512]


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CONSUMER PRODUCT SAFETY COMMISSION

16 CFR Chapter II

[Docket No. CPSC-2019-0020]


Performance Requirements for Residential Gas Furnaces and 
Boilers; Advance Notice of Proposed Rulemaking

AGENCY: Consumer Product Safety Commission.

ACTION: Advance notice of proposed rulemaking.

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SUMMARY: The Consumer Product Safety Commission (Commission or CPSC) is 
considering developing a rule to address the risk of injury and death 
associated with carbon monoxide (CO) production and leakage from 
residential gas furnaces and boilers. This advance notice of proposed 
rulemaking (ANPR) initiates a rulemaking proceeding under the Consumer 
Product Safety Act (CPSA). We invite comments concerning the risk of 
injury associated with CO production and leakage from residential gas 
furnaces and boilers, the alternatives discussed in this ANPR, and 
other possible alternatives for addressing the risk. We also invite 
interested parties to submit existing voluntary standards or a 
statement of intent to modify or develop a voluntary standard that 
addresses the risk of injury described in this document.

[[Page 42848]]


DATES: Submit comments by October 18, 2019.

ADDRESSES: You may submit comments, identified by Docket No. CPSC-2019-
0020, by any of the following methods:
    Electronic Submissions: Submit electronic comments to the Federal 
eRulemaking Portal at: www.regulations.gov. Follow the instructions for 
submitting comments. The Commission does not accept comments submitted 
by electronic mail (email), except through www.regulations.gov. The 
Commission encourages you to submit electronic comments by using the 
Federal eRulemaking Portal, as described above.
    Written Submissions: Submit written submissions by mail/hand 
delivery/courier to: Division of the Secretariat, Consumer Product 
Safety Commission, Room 820, 4330 East West Highway, Bethesda, MD 
20814; telephone (301) 504-7923.
    Instructions: All submissions received must include the agency name 
and docket number for this document. All comments received may be 
posted without change, including any personal identifiers, contact 
information, or other personal information provided, to: 
www.regulations.gov. Do not submit confidential business information, 
trade secret information, or other sensitive or protected information 
that you do not want to be available to the public. If furnished at 
all, such information should be submitted in writing.
    Docket: For access to the docket to read background documents or 
comments received, go to: www.regulations.gov, and insert the docket 
number CPSC-2019-0020, into the ``Search'' box, and follow the prompts.

FOR FURTHER INFORMATION CONTACT: Ronald A. Jordan, Project Manager, 
Directorate for Engineering Sciences, U.S. Consumer Product Safety 
Commission, 5 Research Place, Rockville, MD 20850; telephone: (301) 
987-2219; email: [email protected].

SUPPLEMENTARY INFORMATION: The CPSC \1\ is publishing an ANPR to 
possibly develop a rule to address the risk of injury and death 
associated with CO production and leakage from residential gas furnaces 
and boilers.
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    \1\ The Commission voted 3-2 to publish this document with 
changes in the Federal Register. Acting Chairman Anne Marie Buerkle 
and Commissioners Robert S. Adler and Elliot F. Kaye voted to 
approve publication of this document with changes. Commissioners 
Dana Baiocco and Peter A. Feldman voted to approve publication of 
this document as drafted.
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I. Background

    The Commission is aware of numerous injuries and deaths resulting 
from CO poisoning caused by residential gas furnaces and boilers. Gas-
fired central furnaces and boilers historically have been among the 
leading causes of non-fire CO poisoning deaths associated with consumer 
products. To address this risk, CPSC staff reviewed incident data for 
residential gas furnaces and boilers and determined that residential 
gas furnaces and boilers were involved in a significant number of 
fatalities and injuries from CO poisoning. From 2013 to 2015, there 
were 57 deaths (average 19 deaths per year) related to residential gas 
furnaces and boilers reported to CPSC. In addition, an estimated 7,590 
injuries related to CO poisoning associated with residential gas 
furnaces and boilers were reported to CPSC from 2013 to 2015.
    In the late 1980s, the voluntary standards for a variety of gas 
appliances, including gas furnaces and boilers, were revised to address 
some of the operating, installation, or usage conditions of the 
products that could result in hazards, such as fire, explosion, and 
leakage of CO into the living space. Despite revisions to the voluntary 
standards that addressed some CO hazards, gas furnaces and boilers 
continue to be the second leading cause of CO deaths (portable 
generators are the leading cause of CO deaths \2\ among all consumer 
products) and the leading cause among all heating systems. CPSC staff 
has advocated for more effective performance requirements for gas 
furnaces and boilers since 1993 to protect consumers from CO hazards 
that were not addressed by the voluntary standards for these products.
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    \2\ Non-Fire Carbon Monoxide Deaths Associated with the Use of 
Consumer Products. 2015 Annual Estimates, Hnatov, M. December 2018.
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    Starting in 2000, CPSC staff sought to address CO hazards at the 
source of production (i.e., in the heat exchanger and flue passageways) 
in these appliances by working with voluntary standards organizations 
proposing \3\ that that they add ``CO shutoff/response'' provisions to 
the voluntary standards. Despite repeated requests from CPSC staff for 
the U.S. standards development organizations (SDO) to address the CO 
risk at the source of production in gas appliances, and the existence 
of the Japanese and European performance requirements for CO and 
combustion product sensors, voluntary standards in the United States 
have not adopted similar requirements to address the CO hazard. The 
rationale U.S. SDOs cited for not adopting similar requirements is that 
the CO and combustion product-sensing devices needed to implement the 
requirements must have a 20-year lifespan and that no such devices are 
currently available.
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    \3\ Jordan, R., CO shutoff/response proposal letter Canadian 
Standards Association International, CPSC. November 2000.
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    The Commission is considering developing a mandatory standard to 
reduce the risk of death and injury associated with CO production and 
leakage from residential gas furnaces and boilers. CPSC staff prepared 
a briefing package to describe the products at issue, further assess 
the relevant incident data, examine relevant voluntary standards, and 
discuss options for addressing the risk associated with residential gas 
furnaces and boilers. That briefing package is available at: https://www.cpsc.gov/s3fs-public/Draft%20ANPR%20-%20Performance%20Requirements%20for%20Residential%20Gas%20Furnaces%20and%20Boilers.pdf?izgUebOXOcPhQ51iScglAVrv0NbIb_rB.

II. Relevant Statutory Provisions

    To address the risk of injury associated with CO production and 
leakage from residential gas furnaces and boilers, the Commission is 
considering developing a mandatory safety standard. The rulemaking 
falls under the CPSA. 15 U.S.C. 2051-2089. Under section 7 of the CPSA, 
the Commission may issue a consumer product safety standard if the 
requirements of the standard are ``reasonably necessary to prevent or 
reduce an unreasonable risk of injury associated with [a] product.'' 
Id. 2056(a). The safety standard may consist of performance 
requirements or requirements for warnings and instructions. Id. 
However, if there is a voluntary standard that would adequately reduce 
the risk of injury the Commission seeks to address, and there is likely 
to be substantial compliance with that standard, then the Commission 
must rely on the voluntary standard, instead of issuing a mandatory 
standard. Id. 2056(b)(1). To issue a mandatory standard under section 
7, the Commission must follow the procedural and substantive 
requirements in section 9 of the CPSA. Id. 2056(a).
    Under section 9 of the CPSA, the Commission may begin rulemaking by 
issuing an ANPR. Id. 2058(a). The ANPR must identify the product and 
the nature of the risk of injury associated with it; summarize the 
regulatory alternatives the Commission is considering; and include 
information

[[Page 42849]]

about any relevant existing standards, and why the Commission 
preliminarily believes those standards would not adequately reduce the 
risk of injury associated with the product. The ANPR also must invite 
comments concerning the risk of injury and regulatory alternatives and 
invite the public to submit existing standards or a statement of intent 
to modify or develop a voluntary standard to address the risk of 
injury. Id. 2058(a).
    After publishing an ANPR, the Commission may proceed with 
rulemaking by reviewing the comments received in response to the ANPR 
and publishing a notice of proposed rulemaking (NPR). An NPR must 
include the text of the proposed rule, alternatives the Commission is 
considering, a preliminary regulatory analysis describing the costs and 
benefits of the proposed rule and the alternatives, and an assessment 
of any submitted standards. Id. 2058(c). The Commission would then 
review comments on the NPR and decide whether to issue a final rule, 
along with a final regulatory analysis.

III. The Product

    The ANPR covers residential, gas-fired central furnaces, boilers, 
wall furnaces, and floor furnaces (gas furnaces and boilers). These 
appliances are fueled by natural gas or propane (gas). Residential gas 
furnaces and boilers are vented gas heating appliances that are used to 
heat all categories of consumer dwellings, including single family 
homes, townhomes, condominiums, and multifamily dwellings, as well as 
small-to medium-sized commercial dwellings. These products provide heat 
to a dwelling by burning a mixture of fuel (either natural gas or 
propane) and air within the combustion chamber of a heat exchanger. As 
the mixture of fuel and air is burned, heat is released and transferred 
through the wall of the heat exchanger to the medium surrounding the 
heat exchanger and circulated through air ducts or water pipes 
throughout the dwelling, or into the ambient air to provide heat. 
Burning the mixture of fuel and air results in the formation of 
combustion products that are typically composed of oxygen, carbon 
dioxide, water vapor, and CO. When the mixture of fuel and air is 
burned completely, the concentration of CO produced should remain 
relatively low, typically below 50 parts per million (ppm), depending 
on the design of the gas appliance. The combustion products are 
exhausted to the outdoors through a vent system.
    In a gas-fired central furnace, air is the medium that surrounds 
and is heated by the heat exchanger. A large fan is used to force the 
heated air across the exterior surfaces of the heat exchanger, through 
a duct system, and then the heated air exits the duct system through 
warm air registers in each room within the dwelling. In a gas boiler, 
water in the liquid phase or vapor phase (i.e., steam) is the medium 
that surrounds and is heated by the heat exchanger. The heated water or 
steam is circulated, using a pump to force the fluid through a piping 
system to radiators in each room of the dwelling. Heat is transferred 
from the heated water or steam supplied to the radiators to the room 
through radiative and conductive heat transfer. Gas-fired central 
furnaces and boilers are considered central heating appliances, because 
they provide heat to each room of a dwelling. The combustion products 
of gas-fired central furnaces and boilers are vented to the outdoors, 
either vertically through the roof, or horizontally through a side wall 
through the vent pipe.
    In addition to central gas-fired furnaces and boilers, the ANPR 
also covers gas wall furnaces and gas floor furnaces. As their names 
indicate, gas wall furnaces are installed in wall spaces, typically 
between the wall stud framing members; and floor furnaces are installed 
in the floor, typically between the floor joist framing members. Wall 
furnaces and floor furnaces both provide localized heating directly to 
the room in which they are located, and indirectly to adjoining rooms 
within the dwelling. The combustion products of wall furnaces are 
vented to the outdoors, either vertically through the roof, or 
horizontally through a side wall with the vent pipe running along the 
length of the wall studs between which the unit is installed. The 
combustion products of a floor furnace are typically vented 
horizontally through a side wall, with the vent pipe normally running 
along the length of the floor joists between which the unit is 
installed and through an exterior wall.

IV. Market Information

    Of the gas appliances covered by this ANPR, central gas-fired 
furnaces are the type most commonly used in U.S. households. Natural 
gas and propane central furnaces are the primary heating equipment in 
50.3 million homes; from 2.6 to 3.1 million units were shipped annually 
between 2013 and 2017. Gas boilers are the next most commonly used 
heating appliances in U.S. homes, accounting for the main heating 
source in 6.8 million U.S. homes and about 390,000 annual shipments. 
The average product life of gas furnaces (including boilers) ranges 
from 15 to 20 years. Floor and wall furnaces are less common than 
central furnaces and boilers, but they still accounted for heating in 
800,000 U.S. homes. No annual shipment data were available for floor or 
wall furnaces.

V. Risk of Injury

A. Incident Data

1. Fatalities
    In 2015, (the latest time period for which data are available) 
there were an estimated 175 unintentional, non-fire CO poisoning deaths 
associated with consumer products under the CPSC's jurisdiction.\4\ Of 
that number, heating systems were associated with an estimated 37 (21 
percent) of the deaths. Gas furnaces and boilers (liquefied petroleum, 
natural gas, and unspecified gas) were associated with the largest 
share of CO deaths (19 deaths or 51 percent) among heating systems and 
the second largest share (11 percent) among all consumer products. For 
the 11-year period, 2005 through 2015, gas furnaces accounted for 248 
CO deaths (44 percent) among heating appliances, and 14 percent among 
all consumer products.
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    \4\ Non-Fire Carbon Monoxide Deaths Associated with the Use of 
Consumer Products 2015 Annual Estimates. M. Hnatov. CPSC Directorate 
for Epidemiology. December 2018.
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2. Injury Estimates
    Staff estimates that annually there were about 1,850 gas furnace or 
boiler non-fire, CO-related injuries treated between 2013 and 2015 at 
U.S. hospital emergency departments (EDs).\5\ Combined with estimates 
of medically attended injuries that were treated outside of hospital 
EDs, and using estimates from the CPSC's Injury Cost Model (ICM),\6\ 
staff estimates an average

[[Page 42850]]

of 7,590 non-fire, CO-related injuries annually between 2013 and 2015, 
which were associated with gas furnaces and boilers. This includes the 
estimate from NEISS of 1,850 ED-treated injuries and an additional 
5,750 medically attended cases not treated in EDs.
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    \5\ Physicians have noted difficulty in correctly diagnosing 
these injuries (e.g., Aniol, 1992). Carbon monoxide poisoning may 
mimic many conditions, including alcohol or drug intoxication, 
psychiatric disorders, flulike illnesses, and others conditions that 
can lead to misdiagnoses (ibid). Measurement of HbCO levels in the 
blood can also be confounded, based on the time elapsed and any 
breathing treatment administered that can lower counts before 
measurement. Absent an attempt to provide NEISS cases where carbon 
monoxide was diagnosed, however, it would not be possible to compute 
nonfatal injuries. Thus, a potential underestimate was deemed more 
practical than assuming the injury costs would be zero. Aniol, M.J. 
Carbon Monoxide Toxicity: The Difficulty in Diagnosing This Leading 
Cause of Poisoning. Can Fam Physician. 1992 2123-2134, 2174.
    \6\ The ICM is fully integrated with NEISS and uses empirical 
relationships between the characteristics of injuries and victims 
initially treated in hospital EDs and those treated elsewhere, to 
estimate the number of medically attended injuries treated outside 
of hospital EDs.
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B. Hazard Patterns

    CPSC staff routinely relies on in-depth investigations (IDIs) to 
understand failure modes and conditions that reportedly caused or 
contributed to incidents involving the production and leakage of 
dangerous levels of CO into the living space. For CO exposure to occur 
from a vented gas appliance, two conditions typically must exist. 
First, a condition must exist that prevents complete combustion of the 
fuel. Second, there must be a path or mechanism that allows or causes 
combustion products, including CO, to leak from the flue passageways or 
vent system of the gas appliance into the living space. In 2012, CPSC 
staff conducted reviews of CO-related IDIs that involved ``modern'' 
(i.e., manufactured after 1989) gas furnace or boiler. \7\ Of these 
incidents involving ``modern'' gas appliances, staff identified two 
primary concurrent hazard patterns for CO exposure:
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    \7\ Jordan, R., Updated Review of In-Depth Investigations 
Associated with Carbon Monoxide Poisoning and ``Modern'' Gas 
Furnaces and Boilers. CPSC. September 2012.
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     A condition that resulted in production of a hazardous 
level of CO by the appliance; and
     a condition that allowed hazardous CO to leak into a 
living space.
    Staff confirmed that the failure modes that led to production of 
dangerous levels of CO included too much fuel (i.e., ``overfiring'') to 
the appliance or inadequate air for combustion. The failure modes that 
led to leakage of CO into the living space included: Disconnected or 
breached vents; blocked vents, heat exchangers, or chimneys; 
depressurization of the space or back drafting of exhaust products; and 
improper venting. Staff also determined that the majority of the CO 
incidents occurred from appliances that were reported to be 15 years 
old or less at the time of the incident, and the average age of 
appliances involved in CO incidents was 9.6 years. The average age of 
the appliances indicates that these products were ``modern'' appliances 
equipped with the latest safety devices, and that these safety devices 
were not capable of protecting against CO exposure.
    From review of CO-related IDIs, staff has been able to establish 
the following hazard patterns for gas appliances:
    Incomplete combustion: Complete combustion of hydrocarbon fuels, 
such as natural gas or liquefied petroleum gas (LP-gas or propane), 
requires a proper mixture of air (i.e., combustion air) and fuel, as 
well as an adequate amount of heat to ignite the combustion air-fuel 
mixture. Incomplete combustion of the fuel supplied to gas appliances 
can lead to production of hazardous levels of CO and can occur when the 
following conditions exist:
     Inadequate combustion air: Inadequate air for combustion 
supplied to an appliance occurs when: (1) Air openings to the appliance 
combustion chamber or burner assembly are blocked; (2) combustion air 
inlet piping (in the case of direct vent appliances) to the appliance 
is blocked; (3) the exhaust outlet from the appliance is blocked; (4) 
the appliance is installed in a room that does not have a large enough 
volume to provide the proper amount of air for combustion; or (5) the 
appliance is installed in a smaller room or closet that does not have 
adequately sized combustion and ventilation air openings to support 
proper combustion.
     Too much fuel (i.e., over-firing): Causes of over-firing 
can occur when the appliance gas manifold pressure is too high, causing 
the quantity of fuel delivered to the burner to be too high for 
complete combustion of the fuel/air mixture. This causes incomplete 
combustion of the fuel/air mixture and production of CO. This scenario 
can occur as a result of improper adjustment by a service technician or 
a product defect or component failure/malfunction associated with the 
gas valve or the burner orifice.
     Reduced flame temperature: Inadequate or reduced flame 
temperature can occur when the appliance burner is misaligned, causing 
the burner flame to come into contact with a metal surface within the 
combustion chamber. Because the metal surface is much cooler than the 
burner flame, direct contact will cause a greater rate of heat transfer 
from the flame to the metal, resulting in a reduction in the flame 
temperature (i.e., flame quenching). Depending on the severity and 
duration, all of these conditions can result in incomplete combustion 
of the fuel.
    Exhaust leakage: Combustion products from a gas furnace or boiler 
are normally vented to remove them from the home. However, a potential 
CO hazard in a home can arise when a path or mechanism exists that 
allows or causes CO to leak from the flue passageways or vent system of 
the gas appliance into the living space. Typical leakage paths include: 
(1) A totally or partially blocked vent, chimney, or heat exchanger; or 
(2) a disconnected vent pipe, or a hole in the vent pipe. Sometimes 
leakage can occur when an exhaust fan or fireplace is installed in the 
same room, or in a room adjacent to a gas appliance. The actions of the 
exhaust fan or a warm chimney created by the fireplace can have the 
effect of pulling air out of the room in which the gas appliance is 
installed. This action can depressurize the room, resulting in reverse 
flow of the combustion products through the appliance vent system or 
flue passageways. Instead of being vented safely to the outdoors, 
depressurization can cause combustion products, including CO, to spill 
into the living space. Other mechanisms that can lead to spilling 
include a vent with lower capacity than the gas appliance(s) connected 
to it. This can be caused by total or partial vent blockage, 
installation of a vent pipe that is too small, or the connection of so 
many appliances to the vent that the vent is rendered too small.

VI. Existing Voluntary and International Standards

A. U.S. Voluntary Standards

1. Description of Existing U.S. Voluntary Standards
    The four gas appliance types within the scope of the ANPR are 
covered by the following domestic ANSI Z21 voluntary standards:

 ANSI Z21.13, Standard for Gas-Fired Low Pressure Steam and Hot 
Water Boilers

    This standard specifies the construction and performance 
requirements for gas-fired, low-pressure steam and hot water boilers 
with input ratings of less than 12,500,000 Btu/hr (3,663 kW). The first 
edition of the standard was published in 1934 and has been revised 
several times, with the latest edition published in 2017.

 ANSI Z21.47, Standard for Gas-Fired Central Furnaces

    This standard specifies the construction and performance 
requirements for gas-fired central furnaces with input ratings up to 
and including 400,000 Btu/hr (117 kW). The requirements for gas-fired 
central furnaces were initially included in ANSI Z21.13, before 
becoming a separate standard in 1964. From 1978 through 1993, a 
separate standard for direct vent central furnaces (ANSI Z21.64) was in 
place before being consolidated into a single standard and harmonized 
with Canadian standard requirements in 1993, with the latest edition 
published in 2016.


[[Page 42851]]


 ANSI Z21.86, Standard for Vented Gas-Fired Space Heating 
Appliances

    This standard specifies the construction and performance 
requirements for vented gas-fired space-heating appliances with input 
ratings up to and including 400,000 Btu/hr (117 kW), including vented 
room heaters (Parts III and IV), gravity and fan-type direct-vent wall 
furnaces (Parts V and VI), gravity and fan-type wall furnaces (Part 
VII), gravity and fan-type vented wall furnaces (VIII), and gravity and 
fan-type floor furnaces for the United States only (Parts IX and X). 
The scope of this ANPR only includes gravity and fan-type direct-vent 
wall furnaces (Parts V and VI), and gravity and fan-type floor furnaces 
(IX and X). The ANSI Z21.86 standard was first published in 1998, with 
the latest edition published in 2016; however, individual standards for 
gravity and fan-type direct-vent wall furnaces and gravity and fan-type 
floor furnaces predate this standard and were likely covered in the 
first edition of ANSI Z21.13.
    The voluntary standards listed above all require the appliances to:
     Not produce CO in excess of 400 ppm;
     shut off when vent or flue is fully blocked;
     shut off when blower door is not sealed properly (gas-
fired central furnaces only);
     shut off if flames issue outside of the burner inlet 
openings.
2. Assessment of Existing U.S. Voluntary Standards
    Despite the requirements of the ANSI Z21 voluntary standards, as 
well as a number of improvements to these standards that have been made 
over the years, these standards do not include requirements to protect 
against many of the failure modes or conditions that have been 
associated with production and leakage of CO into living spaces of U.S. 
households. Furthermore, the voluntary standards requirements do not 
address the long-term use of the products once installed in a dwelling 
or the various conditions that can cause or contribute to CO production 
and leakage. There are a number of leakage paths or mechanisms by which 
CO can leak into a living space; however, the ANSI Z21 standards for 
gas furnaces, boilers, wall furnaces, and floor furnaces only address 
leakage caused by a totally blocked vent. Staff has identified a 
variety of conditions that are not addressed by the ANSI requirements. 
Those conditions include, but are not limited to:
     Disconnected or breached flues, vents, and chimneys;
     partially blocked heat exchangers, flues, vents, and 
chimneys;
     over-fired appliances; and
     inadequate combustion air to appliances.
    Based on the hazard patterns identified in the staff's review of 
fatal CO poisoning incidents involving gas appliances, requirements to 
address CO risk at the source of production, before potentially deadly 
levels of CO can enter the living space, would reduce the occurrence of 
CO-related deaths, injuries, and exposures associated with gas 
furnaces, boilers, wall and floor furnaces.
    In 2015, CPSC staff proposed requirements for CO shutoff/response 
to the respective voluntary standards development organizations for 
gas-fired central furnaces, boilers, wall furnaces, and floor furnaces. 
Staff's proposal would have required the appliance to limit the 
production of CO below a threshold level, or for the appliance to shut 
off when CO emissions in the combustion chamber, flue passageways, or 
vent pipe exceed a hazardous level. The 2015 staff proposal was 
supported by the proof-of-concept testing \8\ previously conducted by 
CPSC staff in 2001, 2004, and 2007, and by current standards for gas 
appliances in Europe and Japan, which include similar requirements to 
use combustion sensors to regulate CO production and shut down the 
appliance or modulate its performance if CO production exceeds a 
specified safe level. To date, no revisions to the ANSI Z21 voluntary 
standards have been made that incorporate staff's proposed performance 
requirements to address the hazard patterns discussed above. Therefore, 
the existing ANSI Z21 voluntary standards currently do not adequately 
address the risk of injury and death associated with CO production and 
leakage from residential gas furnaces and boilers for the reasons 
discussed above.
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    \8\ This testing was initially used to support a CO shutoff/
response requirements proposed by CPSC staff to the same voluntary 
standards organizations in 2001.
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B. International Standards

1. Japanese Gas Appliance Standards
    The primary gas heating appliances used in Japan appear to be gas 
water heaters, gas boilers, and gas space heaters. Based on our limited 
review of the Japanese gas appliance market, instantaneous, tankless 
gas water heaters appear to be more common than traditional gas water 
heaters with storage tanks. The governing voluntary performance and 
safety standards for these appliances in Japan are:
     JIS-S-2109--Gas burning water heaters for domestic use
     JIS-S-2112--Gas hydronic heating appliances for domestic 
use \9\
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    \9\ JIS-S-2112 and JIS-S-2122 were not available in English. To 
confirm the existence of incomplete combustion preventive device 
requirements with these standards, the table of contents and 
sections of the standards pertaining to incomplete combustion, 
carbon monoxide, and CO were translated from Japanese to English 
using: https://www.bing.com/search?q=translate+from+japanese+to+english&form=IENTHT&mkt=en-us&httpsmsn=1&refig=ffc0d5a3070d45d3c5187baeb690b6dd&sp=1&ghc=1&qs=AS&pq=translate+from+japanese+to+english≻=8-34&cvid=ffc0d5a3070d45d3c5187baeb690b6dd. Staff's partial 
translation and review of these standards confirmed that they both 
included requirements for devices to prevent incomplete combustion 
to protect against CO poisoning and that were consistent with the 
requirements in JIS-S-2109.
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     JIS-S-2122--Gas burning space heaters for domestic use.
    These Japanese Industrial Standards (JIS) have explicit performance 
requirements for vented gas water heaters, gas boilers, and gas space 
heaters that require shutoff of the appliance in response to CO levels 
above a certain threshold (i.e., 300 ppm CO). The CO-detection 
strategies used by Japanese manufacturers include detection of CO 
within the combustion chamber of the appliance and shutoff or 
combustion control in response to detection of hazardous levels of CO.
    Although gas water heaters are not within the scope of the ANPR, 
the Japanese standard, JIS-S-2109, is relevant because the combustion 
process and technology involved in heating water is similar to the 
combustion process and technology used for gas furnaces and boilers 
sold in the United States. In addition, the Japanese standard's CO 
shutoff requirements are similar to CPSC staff's 2000 and 2015 CO 
shutoff/response proposals, and the CO detection and combustion 
components are applicable to gas furnaces and boilers sold in the 
United States.
    To protect against CO exposure, JIS-S-2109 includes requirements 
that vented gas water heaters be equipped with what they call an 
``Incomplete Combustion Prevention Device'' (ICPD). A gas appliance 
experiencing incomplete combustion means that the fuel is not being 
burned or combusted completely, and as a result, can produce elevated 
concentrations of CO. Section 7.7.6 of JIS-S-2109, Incomplete 
Combustion Preventive Device of FE includes requirements that the water

[[Page 42852]]

heater shut off when CO concentrations reach 0.03 percent (300 ppm) 
\10\ in:
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    \10\ 0.03 percent converts to 300 ppm CO by multiplying 0.03 
percent by 10,000.
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     The room in which the water heater is installed; and
     the adjacent room.
    According to the Japanese Standards Association (JSA), the 
Incomplete Combustion Preventative Device provisions in JIS-S-2109 have 
been required since 2001. JSA also indicated that JIS-S-2109 does not 
have separate performance standards for ICPDs, requirements for a 
minimum life span for the device, and that these devices are replaced, 
if necessary, based on use and functionality. All of the performance 
requirements for ICPDs are specified in JIS-S-2109. In addition, JIS-S-
2109 includes flame roll-out and blocked vent requirements 
(respectively, similar to the Flame Roll-Out and Blocked Vent Safety 
requirements in ANSI Z21.13 and ANSI Z21.47).
    Another similarity between the ICPD requirements of JIS-S-2109 and 
CPSC staff's 2000 and 2015 CO shutoff/response proposals is that they 
both necessitate that the device be within the harsh environment of 
appliance combustion chamber, flue passageways, or vent system.
2. European Gas Appliance and Combustion Sensor Standards
    Gas boilers are a common space-heating appliance used throughout 
Europe in residential settings, and they are similar in design and 
function to residential gas boilers certified to ANSI Z21.13 and sold 
in the United States. The relevant European Committee for 
Standardization (CEN) domestic gas boiler standards are:
     EN 15502-1, Gas-fired heating boilers, Part 1: General 
requirements and tests;
     EN 15502-2-1, Gas-fired central heating boilers, Part 2-1: 
Specific standard for type C appliances and type B2, B3 and B5 
appliances of a nominal heat input not exceeding 1000 kW; and
     EN 15502-2-2, Gas-fired central heating boilers, Part 2-2: 
Specific standard for type B1 appliances.
    These standards (EN 15502-1, EN 15502-2-1, and EN 15502-2-2) 
include requirements to ensure the proper supply of combustion air and 
gas to the combustion process (i.e., air proving) through the use of 
one of the following mechanisms:
     Carbon Monoxide (EN 15502-1, EN 15502-2-1, and EN 15502-2-
2);
     Supervision of the combustion air pressure or the 
combustion products pressure (EN 15502-1);
     Supervision of the combustion air rate or the combustion 
products rate (EN 15502-2-1 and EN 15502-2-2);
     Gas/air ratio control (EN 15502-1, EN 15502-2-1, and EN 
15502-2-2); or
     Indirect supervision (e.g., fan speed supervision) (EN 
15502-1).
    The second and third bullets listed above, Supervision of the 
combustion air rate or the combustion products rate, and Gas/air ratio 
control, are the most similar to CPSC staff's 2000 and 2015 CO Shutoff 
proposals to the ANSI Z21/83 Technical committee and furnace and boiler 
subcommittees. Additionally, these standards include performance 
requirements for blocked vents.
    These standards also have combustion product discharge provisions, 
which are similar to the Flame Roll-Out provisions of the ANSI 
standards (i.e., ANSI Z21.13 and ANSI Z21.47).
    In addition to the common requirements for all three of the 
standards, EN 15502-2-1 also includes test conditions and CO emission 
limits for: Boilers without gas/air ratio controls (Section 8.12.2.101) 
and Boilers using gas/air ratio controls (Section 8.12.2.102). Both 
requirements specify that the maximum permissible CO concentration not 
exceed 0.10 percent (1,000 ppm). EN 15502-2-2 includes a provision, 
Section 8.12.101, Supplementary test for natural draught boilers, which 
specifies that the maximum permissible CO concentration not exceed 0.10 
percent (1,000 ppm).
    Unlike the JIS standards, the CEN includes separate standards for 
combustion monitoring devices and controls that are used in domestic 
gas boilers. The relevant CEN standards are:

 EN 13611, Safety and control devices for burners and 
appliances burning gaseous and/or liquid fuels--General requirements

    This standard specifies the general safety, design, construction, 
and performance requirements and testing for safety, control, or 
regulating devices use for burners or appliances burning gaseous or 
liquid fuels. The standard is designed to be used in conjunction with 
the various CEN standards that govern the above types of control 
devices. Because they address combustion process monitoring and 
modulation, EN 12067-2 and EN 16340 are of particular relevance to this 
ANPR.

 EN 12067-2, Gas/air ratio controls for gas burners and gas 
burning appliances--Part 2: Electronic types

    This standard specifies the safety, construction, and performance 
requirements for closed-loop electronic gas/air ratio control systems 
(GARCs) for use with gas burners and gas-burning appliances. A GARC 
provides the electromechanical interface to the burner or the gas valve 
and the combustion air supply that allows these devices to be modulated 
or controlled to increase or decrease gas flow or combustion air flow. 
This allows the GARC to maintain the combustion efficiency of the 
appliance by monitoring and maintaining an optimal gas/air ratio. An 
optimal gas/air ratio ensures that the gas/air mixture supplied to the 
appliance burner is burned completely, thereby maintaining combustion 
efficiency.

 EN 16340, Safety and control devices for burners and 
appliances burning gaseous or liquid fuels--Combustion product sensing 
devices

    This standard specifies the safety, construction, and performance 
requirements for combustion product-sensing devices (CPSD) designed to 
measure combustion products, as part of combustion control systems for 
burners and appliances that operate by burning gaseous or liquid fuels. 
This standard covers sensing devices that measures CO, as well as other 
flue gases. This standard is designed to be used in conjunction with EN 
13611, Safety and control devices for burners and appliances burning 
gaseous and/or liquid fuels--General requirements.
    We note the similarities to CPSC staff's voluntary standards CO 
Shutoff/Response proposals. EN 16340 is compatible with CPSC staff's CO 
shutoff/response proposals because it establishes performance 
requirements for a device that monitors: (1) Within the same parameters 
(i.e., combustion gases, including CO); and (2) within the same harsh 
environment (i.e., the combustion chamber). Consequently, these devices 
are subject to the same harsh operating conditions (i.e., high 
operating temperature, relative humidity, combustion gases, thermal 
cycling) that the Z21/83 Technical Committee and its subordinate 
technical subcommittees (for gas furnaces and boilers) and CO/
combustion sensor working groups raised questions about in response to 
CPSC staff's 2000 and 2015 CO shutoff/response proposals.
3. International Standards as Examples of Technological Feasibility
    A lack of technological feasibility can be a barrier to 
implementing a new or proposed standard. Therefore, CPSC staff has 
sought to identify technologies that might be capable of implementing 
the staff-recommended CO shutoff/response proposals made to voluntary 
standards groups in 2000 and 2015. In addition, staff has also assessed

[[Page 42853]]

international standards that required the same or similar performance 
requirements as staff's 2000 and 2015 CO shutoff/response proposals. 
The Japanese and European standards discussed above identify several 
gas-sensing technologies that are being used for CO shutoff or 
combustion control of residential gas appliances in Japan and Europe. 
As discussed, the CO-detection strategies used by Japanese 
manufacturers include detection of CO within the combustion chamber of 
the appliance and shutoff or combustion control in response. In Europe, 
residential gas boilers are required to meet certain combustion-
efficiency requirements, as well as CO safety requirements. The 
combustion-control strategies used by European gas boiler manufacturers 
are often accomplished by monitoring the gas/air mixture, the 
combustion flame, or the concentration of CO, oxygen, or carbon dioxide 
within the combustion products. The combustion-control strategies are 
also used to detect CO, but rather than shutting down the appliance, CO 
production is either prevented or limited by modulating the appliance's 
operation. The Japanese and European standards do not specify a minimum 
lifespan for sensing devices used to implement their respective CO 
safety and combustion efficiency requirements.
    The Japanese and European standards demonstrate that it is 
technologically feasible, using current technology, to address the 
hazard patterns identified by staff regarding CO poisoning in a safety 
standard. The Japanese and European standards discussed above are 
examples of existing international standards that address the risk of 
injury and death associated with CO production and leakage from 
residential gas furnaces and boilers that are the subject of this ANPR.

VII. Regulatory Alternatives the Commission Is Considering

    The Commission is considering several alternatives to address the 
risk of death and injury associated with CO poisoning from residential 
gas furnaces and boilers.

A. Mandatory Standard

    The Commission could develop a rule under the CPSA establishing 
performance requirements and/or warnings and instructions for 
residential gas furnaces and boilers to prevent or reduce an 
unreasonable risk of death or injury associated with the production and 
leakage of CO from these products.

B. Rely on Voluntary Standards

    The Commission could continue to address the hazard through 
voluntary standards, ANSI Z21.13, ANSI Z21.47, and ANSI Z21.86, and 
continue to work to develop more effective voluntary standard 
requirements to address the identified hazards, instead of issuing a 
mandatory rule. However, as previously discussed, the Commission 
preliminarily believes that the existing ANSI standards do not 
adequately reduce the risk of injury associated with residential gas 
furnaces and boilers. The Commission is assessing the level of 
compliance with the voluntary standards.

C. Reliance on Recalls

    The Commission has recalled residential gas furnaces and boilers 
related to CO leakage hazards. The Commission could continue to conduct 
recalls, both voluntary and mandatory, instead of promulgating a 
mandatory rule. However, recalls may not be as effective at reducing 
the risk of injury as a mandatory standard. Recalls only apply to an 
individual manufacturer and product and do not extend to similar 
products. Additionally, recalls can only address products that are 
already on the market, and cannot prevent unsafe products from entering 
the market.

D. Information and Education Campaign

    The Commission could continue to issue annual and semi-annual news 
releases warning consumers about the dangers of CO poisoning and 
promoting the importance of consumers getting annual safety inspections 
of their residential fuel burning heating systems.

VIII. Request for Comments and Information

    The Commission requests comments on all aspects of this ANPR, but 
specifically requests comments regarding:
     Information or analysis regarding mechanisms or 
performance requirements to mitigate more effectively the following 
hazard patterns that lead to CO production and leakage:

    [cir] Inadequate air for combustion supplied to the appliance;
    [cir] Too much fuel supplied to the appliance burner (i.e., over-
firing);
    [cir] Reduction of burner flame temperature below the ignition 
temperature of the combustion air-fuel mixture (i.e., flame quenching);
    [cir] Disconnected or breached vent pipe, chimney, heat exchanger, 
or flue passageway;
    [cir] Partially blocked vent pipe, chimney, heat exchanger, or flue 
passageways;
    [cir] Snow blockage of side-wall vented gas appliances;
    [cir] Improperly sized vent pipes; and
    [cir] Depressurization of the room in which the gas appliance is 
installed.
     Studies, tests, analysis, or surveys performed to evaluate 
the effectiveness of gas-sensing and shut-off devices and performance 
standards, laws, or codes in reducing carbon monoxide fatalities and 
injuries associated with the use of domestic gas furnaces, boilers, 
water heaters and other gas heating appliances in Europe and Japan;
     Studies or analysis of the costs of incorporating carbon 
monoxide sensors or combustion controls systems into residential gas 
furnaces, boilers, or water heaters in Japan, Europe, or the United 
States;
     Studies or analyses that evaluate secondary cost impacts 
of using gas-sensing and shut-off devices in reducing carbon monoxide 
fatalities and injuries associated with the use of domestic gas 
furnaces, boilers, water heaters, and other gas heating appliances in 
Europe and Japan;
     Studies or analyses that evaluate the impact of carbon 
monoxide fatalities and injuries associated with the use of domestic 
gas furnaces, boilers, water heaters and other gas heating appliances 
in Europe and Japan;
     Data or analyses on the alternatives the Commission is 
considering, including the cost and effectiveness of the CO shutoff/
response requirements under consideration;
     Studies, test, or analyses that correlate the effects of 
incomplete combustion to carbon monoxide production and changes in the 
combustion efficiency of natural gas and propane appliances.
     Information on any factors or trends that, independent of 
any CPSC rulemaking, could act to reduce (or increase) CO poisoning 
associated with gas furnaces, boilers, wall furnaces, and floor 
furnaces described in the ANPR;
     Information on any feasible means of addressing this 
hazard, along with the specific costs that might be involved, including 
information on the costs associated with the maintenance over the 
service life of the equipment that would likely result from potential 
remedies. We also request information on how effective the different 
remedies would be in reducing the hazard;
     Standards in Japan and some European Union countries 
require some gas appliances to have a means by which CO production or 
perhaps fuel consumption is measured. We request

[[Page 42854]]

information on those standards, the means by which compliance with the 
standards is achieved, the impact of the standards on the cost of 
equipment, including the maintenance costs, and the effectiveness of 
the standards at achieving their intended purpose;
     Any available information on the distribution of CO 
emissions of natural or LP gas furnaces in use, or in other words, the 
number of gas furnaces that are not in compliance with the 400 ppm air-
free standard at any given time and the degree to which they might be 
producing CO in excess of that standard. We also request information on 
the causes of equipment producing excessive CO and their frequency of 
occurrence, such as improper installation, changes in installation, 
poor maintenance of the equipment, and so forth; and
     Any available information on the relationship between 
excessive CO production and fuel consumption and complete/incomplete 
combustion in residential furnaces and boilers that are producing 
excessive CO emissions may also be consuming excessive fuel or not 
burning fuel completely.
     Any available information on methods of alerting consumers 
to the need to replace sensors or combination controls that have 
stopped working on their furnaces or boilers (such as an alphanumeric 
LED trouble or error code, a flashing light, or short-cycling of the 
appliance).
    In addition, the Commission invites interested parties to submit 
any existing standards, or portions of them, for consideration as a 
consumer product safety standard. The Commission also invites 
interested persons to submit a statement of intention to modify or 
develop a voluntary consumer product safety standard addressing the 
risk of injury associated with CO poisoning from residential gas 
furnaces and boilers, including a description of the plan to develop or 
modify such a standard.
    Please submit comments in accordance with the instructions in the 
ADDRESSES section at the beginning of this ANPR.

Alberta E. Mills,
Secretary, U.S. Consumer Product Safety Commission.
[FR Doc. 2019-17512 Filed 8-16-19; 8:45 am]
 BILLING CODE 6355-01-P