Interpretation ID: 17506-r.wkm

Mr. Chris Cardwell
Manufacturing Engineer
McKechnie Vehicle Components
Fluid Handling Division
Post Office Box 537
Newberry, SC 27108

Dear Mr. Cardwell:

Please pardon the delay in responding to your letter to this office in which you ask for an "official ruling" as to whether the plastic tubing you produce is subject to Federal Motor Vehicle Safety Standard (Standard) No. 106, Brake hoses, or any other Federal motor vehicle safety standard.

You state that your company intends to produce plastic tubing for use in the model year 2000 Ford Escort. The tubing will be utilized as low-pressure brake fluid return lines running from the clutch to the brake fluid reservoir and from the fluid reservoir to the brake master cylinder. The fluid in these lines will not be under pressure since the reservoir is open to the atmosphere. You feel that for that reason, these tubes are not subject to Standard No. 106.

Standard No. 106 applies to new motor vehicles and to "hydraulic, air, and vacuum brake hose, brake hose assemblies, and brake hose end fittings...." The term "brake hose" is defined in pertinent part in S4 of the standard as:

[A] flexible conduit, other than a vacuum tubing connector, manufactured for use in a brake system to transmit or contain the fluid pressure or vacuum used to apply force to a vehicle's brakes.

Hoses are excepted from Standard 106 if they do not transmit or contain the brake fluid pressure or vacuum used to apply force to a vehicle's brakes. To determine whether the hoses you produce are excluded from the standard, you must determine whether a failure of your hose would result in a loss of pressure in the brake system. If this would be the case, the hoses transmit or contain the pressure used to apply force to the vehicle's brakes and therefore would have to comply with the standard. (See NHTSA's August 3, 1984 letter to Eaton Corporation, copy enclosed, concerning small diameter hoses used on air brake equipped trucks.) Failure of a conduit that transmits or contains the pressure used to apply force to a vehicle's brakes would either immediately or eventually affect the vehicle's braking performance. It is important, therefore, for such hoses to meet the performance requirements of Standard 106, to reduce the likelihood of failure in service. If you use a check valve or some other device to prevent loss of pressure, then the hose would not contain or transmit the pressure and would not be required to comply with Standard 106.

I hope this information is helpful to you.

Sincerely,
Frank Seales, Jr.
Chief Counsel
Enclosure
ref:106
d.6/5/98