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Interpretation Response #14-0025 ([Veolia ES Technical Solutions, L.L.C.] [Ms. Jennifer Eberle])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Veolia ES Technical Solutions, L.L.C.

Individual Name: Ms. Jennifer Eberle

Location State: NJ Country: US

View the Interpretation Document

Response text:

April 1, 2014

Ms. Jennifer Eberle
Manager, Transportation Compliance
Veolia ES Technical Solutions, L.L.C.
1 Eden Lane
Flanders, NJ  07836

Ref. No.:  14-0025

Dear Ms. Eberle:

This responds to your February 10, 2014 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the audible warning device requirements of § 173.21(f)(3)(i)(C) when transporting self-reactive or organic peroxide materials requiring temperature control.  Your questions are paraphrased and answered as follows:

Q1. Would use of a vehicle operator's mobile device to receive SMS text messages (sent from the mechanical refrigeration unit by means of an electronic temperature probe) set to a specific sound tone used only for alerts related to the temperature of the refrigeration unit meet the definition of an audible warning device as required in §173.21(f)(3)(i)(C)?

A1. The answer is yes.  Section 173.21(f)(3)(i)(C) states that the warning device must be readily visible or audible, as appropriate, from the vehicle operator's seat in the vehicle.  A specific sound tone audible on the operator’s mobile device would satisfy this requirement.  

Q2. Would such use of the vehicle operator's mobile device set to receive audible warnings violate the prohibitions in §177.804(b)(2) and (3) if the motor carrier does not allow or require the driver to provide a message in response to the alert until he or she has safely parked and is no longer driving the vehicle?

A2. The answer is no.  A specific sound tone that would not require the operator to view or handle the mobile device while driving would not violate the prohibitions in §177.804(b)(2) and (3).

I hope this satisfies your inquiry.  Please contact us if we can be of further assistance.


Duane A. Pfund
International Standards Coordinator
Standards and Rulemaking Division

173.21, 177.805

Regulation Sections

Section Subject
173.21 Forbidden materials and packages
177.804 Compliance with Federal Motor Carrier Safety Regulations