[Federal Register Volume 60, Number 198 (Friday, October 13, 1995)]
[Proposed Rules]
[Pages 53328-53329]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-25405]



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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration

49 CFR Part 571


Federal Motor Vehicle Safety Standards

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation (DOT).

ACTION: Denial of petition for rulemaking.

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SUMMARY: This document denies a petition for rulemaking submitted by 
the Commonwealth of Pennsylvania Department of Transportation. The 
petitioner requested that NHTSA issue regulations to reduce the 
potential for tire tread separation and casing failure from new or 
retreaded truck tires, including regulations that ensure the stability 
of re-used casings, prescribe a maximum life of casings, and minimize 
truck rim separations. While NHTSA shares the petitioner's safety 
concerns, the agency believes that issuance of new safety requirements 
for tires and rims would not be an appropriate way of addressing this 
problem, which is primarily related to poor vehicle maintenance rather 
than to tire and rim performance.

FOR FURTHER INFORMATION CONTACT: Ms. Terri Droneburg, Office of Vehicle 
Safety Standards, National Highway Traffic Safety Administration, 400 
Seventh Street SW., Room 5307, Washington, DC 20590. Telephone (202) 
366-6617; facsimile (202) 366-4329. For legal issues: Mr. Walter Myers, 
Office of Chief Counsel, National Highway Traffic Safety 
Administration, 400 Seventh Street SW., Room 5219, Washington, DC 
20590. Telephone (202) 366-2992; facsimile (202) 366-3820.

SUPPLEMENTARY INFORMATION:

Existing Standards

    Federal Motor Vehicle Safety Standard (Standard) No. 117, Retreaded 
pneumatic Tires, establishes performance, labeling, and certification 
requirements for retreaded pneumatic passenger car tires. Among other 
things, the standard requires retreaded passenger car tires to comply 
with the tubeless tire resistance to bead unseating and the tire 
strength requirements of Standard No. 109, New pneumatic tires. 
Standard No. 117 also specifies requirements for casings to be used for 
retreading, and certification and labeling requirements.
    With respect to rims, Standard No. 110, Tire selection and rims, 
applicable to passenger cars, establishes rim dimension requirements 
and further specifies that in the event of a sudden loss of inflation 
pressure at a speed of 60 miles per hour, rims must retain a deflated 
tire until the vehicle can be stopped with a controlled braking 
application. Standard No. 120, Tire selection and rims for motor 
vehicles other than passenger cars, requires that vehicles other than 
passenger cars equipped with pneumatic tires be equipped with rims that 
are listed by the tire manufacturer as suitable for use with those 
tires, and that rims be labeled with certain information.

The Petition

    The Commonwealth of Pennsylvania (COP) Department of Transportation 
submitted a petition for rulemaking requesting that NHTSA issue 
regulations ``to reduce the potential for tread separation and casing 
failure from new or re-cap truck tires.'' COP further requested that 
the agency consider regulations ensuring the stability of re-used tire 
casings that may require establishing a maximum life of casings. 
Finally, COP requested that regulations be issued to ``further minimize 
the potential for truck rims from separating from moving vehicles.''
    COP stated that over the past several years it has noticed an 
increase in separation of tire treads from truck tires and separations 
from truck rims. COP stated that this is a dangerous situation in that:
    * Other vehicles, especially passenger cars, vans, and motorcycles 
can strike these tread separations, causing the vehicles to go out of 
control and crash;
    * With increased travel on the interstate highways the probability 
of striking these pieces increases, particularly at night when 
visibility is limited;
    * Law enforcement officers and highway maintenance personnel are 
vulnerable when trying to remove such debris from the roadways;
    * Although COP's crash data does not readily identify crashes 
resulting from striking tread debris on the road, COP has identified 15 
cases in which tire portions caused crashes in 1993, and 2 crashes 
resulting from vehicles striking truck rims on highways in 1993. 

[[Page 53329]]

    COP noted that there are standards for retreaded tires for 
passenger cars, but not for vehicles other than passenger cars, and 
stated that the problem is sufficiently significant to petition NHTSA 
to take the actions discussed above.

Agency Decision

    After a full and careful analysis of the requests of the COP in the 
petition and the supporting rationale, NHTSA has decided to deny the 
petition. The agency shares COP's concerns about the risk of crashes 
created by tire scraps and broken wheels in the highway. However, NHTSA 
believes that issuance of new safety requirements for tires and rims 
would not be an effective way of addressing the problem, since the 
problem is primarily related to poor vehicle maintenance rather than to 
tire and rim performance.
    Available information shows that tire tread separation results not 
from failure of unstable tire casings, used or new, but from improper 
use and/or poor tire maintenance. The University of Michigan conducted 
a study entitled ``Large Truck Accidents Involving Tire Failure'' which 
concluded that tread separation results from overloading and/or 
underinflation of tires which can cause tread failure on both new as 
well as retreaded tires. Specifically, the study showed that of tire 
scraps collected nationwide, approximately 60 percent were from 
retreads and 40 percent from original treads.
    The cause of tire tread separations is related to the fact that 
heat is a tire's worst enemy. A pneumatic tire will flex and heat up 
during the first few miles of operation. If properly inflated, the air 
pressure in the tire will increase until the heat generation due to 
flexing and the heat loss due to ambient cooling reach equilibrium. 
Underinflation and/or overloading, however, can distort that 
equilibrium and cause the tire to produce very high temperatures, 
ultimately beyond the capability of the tire to adequately dissipate. 
At highway speeds, underinflation and/or overloading can produce tire 
temperatures up to 240 deg.-265 deg. Fahrenheit. Such extreme 
temperatures can cause tire disintegration, sidewall failure and/or 
tread separation, regardless of the soundness of the casing.
    The danger posed by underinflation/overloading of tires prompted 
the Federal Highway Administration (FHWA), DOT, to issue regulations 
prohibiting the operation of commercial vehicles under conditions of 
tire underinflation or overloading (49 CFR 393.75). FHWA enforces those 
requirements by roadside inspection programs.
    Available data show that the great majority, if not nearly all, 
tire and rim scraps on the roads are from vehicles other than passenger 
cars. While the problem of tire underinflation is common both to 
passenger cars and trucks, passenger cars are seldom operated in a 
fully loaded condition. That is not the case with trucks, however, 
especially commercial trucks which, for economic reasons, are often 
loaded up to their gross vehicle weight rating (GVWR). For that reason, 
therefore, when tires are underinflated, the likelihood of tire failure 
is much greater for trucks than for passenger cars.
    With regard to rims, the potential problem with wheel rims is not 
so much that they break apart, but that the entire wheel and rim 
assembly separates from the vehicle. Again, the leading causes of such 
wheel separations from medium and heavy trucks, which constitute 
approximately 0.3 percent of all truck accidents, are improper 
tightening of wheel fasteners and bearing failure. Both those factors 
are the result of inadequate or improper wheel maintenance.
    For the reasons discussed above, NHTSA believes that improper 
maintenance is primarily responsible for tread and wheel failure, 
rather than tire/rim performance or unstable casings being used for 
retreaded tires. Moreover, the agency is not aware of changes to tires 
or rims that would address these problems. NHTSA therefore believes 
that issuance of new safety requirements for tires and rims would not 
be an appropriate or effective way of addressing the problems. Thus, 
there is no reasonable probability that this agency would issue the 
requested regulations at the conclusion of a rulemaking proceeding. 
Accordingly, the petition of COP is denied.
    NHTSA will continue to emphasize the importance of proper vehicle 
maintenance, including proper tire inflation, in its various activities 
and encourages similar efforts by other public and private sector 
organizations.

    Authority: 49 U.S.C. Secs. 322, 30111, and 30162; delegation of 
authority at 49 CFR 1.50.

    Issued on October 6, 1995.
Barry Felrice,
Associate Administrator for Safety Performance Standards.
[FR Doc. 95-25405 Filed 10-12-95; 8:45 am]
BILLING CODE 4910-59-P