Chemical Tankers / Day 2 / Day 2 Topic 1 USCG Chemical Guide

1.5 Explanation of physical properties of cargo

o Specific gravity

This is a ratio of the weight of a volume of the cargo to the weight of an equal volume of water.

If the specific gravity is greater than 1, the product will sink in the water. If the specific gravity is less then 1, the product will float. (Useful when considering a tank cleaning plan)

1.5 Explanation of physical properties of cargo

oChemical family

This is general chemical category / group which facilitates the use of the Compatibility Chart for predicting the type of reactions that can be expected between different groups of chemicals.

1.5 Explanation of physical properties of cargo

o Pollution Category - USEPA & IMO

USEPA – US Environmental Protection Agency. Assigned the cargoes for domestic user information to the categories.

Categories X, A, B, C, D – associated with reportable quantities of 1, 10, 100, 1.000 and 5.000 pounds respectively in the event of spill. See 40 CFR table 302.4 for reference.

1.5 Explanation of physical properties of cargo

IMO – X, Y, Z (still old categories A, B, C, D exists) - NLS Category of Annex II of MARPOL 73/78;

I – Considered an oil under Annex I of MARPOL 73/78. See page 410 for complete list;

1.5Explanation of physical properties of cargo

#- No determination of NLS status. For shipping on oceangoing vessels, see 46 CFR 153.900©;

@ - The NLS Category has been assigned by U.S. Coast Guard, in absence of one assigned by the IMO. The category is based upon GESAMP Hazard Profile or by analogy to a closely related product;

1.5 Explanation of physical properties of cargo

“gas” – The IMO generally does not assign Pollution Cat. to gases as these cargoes present little to no hazard to the aquatic environment;

Applicable Bulk Regulation 46 CFR Subchapter – In the blank is indicated the CFR reference for the carriage of the commodity;

1.5 Explanation of physical properties of cargo

o United Nations Number (UN)

The number assigned to a particular cargo by the United Nations (may be discontinued in an updated edition);

o CHRIS Code

The three letter designation assigned to every entry in the Chemical Hazard Response Information System;

1.5 Explanation of physical properties of cargo

Physical Properties & Regulatory Classification

1.5 Explanation of physical properties of cargo

o Boiling Point

The temperature at which the liquid boils. Given in “C” and “F” at pressure of 760 mm Hg, one atmosphere or 14.7 psi.