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Interpretation Response #07-0155 ([Sea Star Line LLC] [Mr. Shawn Burke])

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

Interpretation Response Details

Response Publish Date:

Company Name: Sea Star Line LLC

Individual Name: Mr. Shawn Burke

Location State: NJ Country: US

View the Interpretation Document

Response text:

Oct 16, 2007

Mr. Shawn Burke                                        Reference No. 07-0155

Manager, Terminal Operations

Sea Star Line LLC

Elizabeth, New Jersey 07207

Dear Mr. Burke:

This responds to your August 9, 2007 fax requesting clarification on the definition of ventilation related terms under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask for the definitions of "ventilated", "well ventilated", and "mechanically ventilated" holds in vessels under the HMR.

Generally, there are two types of ventilation for a cargo hold: mechanical ventilation and natural ventilation. Mechanical ventilation can be simply defined as power-generated ventilation. For Safety of Life at Sea (SOLAS) vessels, this typically means at least six air changes per hour in the cargo space, based on an empty cargo space, and the removal of vapors from the upper or lower parts of the cargo space. This definition can be found in SOLAS Chapter II-2 Regulation 19. Natural ventilation is simply ventilation that is not power-generated. This type of ventilation usually takes the form of openings, vents, or goosenecks in the cargo hold.

Under the HMR, "ventilated" means the removal of dangerous vapors and gas from the cargo hold. Either natural or mechanical ventilation may be used provided the ventilation system has the capacity to prevent a dangerous accumulation of vapors or gases. For purposes of the Part 176 of the HMR, "well ventilated" has the same meaning as "ventilated."

I hope this answers your inquiry.


John A. Gale

Chief, Standards Development

Office of Hazardous Materials Standards

171.8, 176.305(1)

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
176.305 General stowage requirements