Circular Letter MSC/Circ.1046

GUIDELINES FOR THE ASSESSMENT OF THERMAL PROTECTION

(adopted on 21 May 2002)

1. The Maritime Safety Committee, at its seventy-fifth session (15 to 24 May 2002), recognizing the need for systematised guidelines for thermal protection of crews and passengers ac­cording to environmental factors and for appropriate perfor­mance standards for additional thermal protective equipment, approved Guidelines for the assessment of thermal protection, as set out in the Annex.

2. Member Governments are invited to bring the annexed Guide­lines to the attention of all parties concerned, as appropriate.

Annex.

GUIDELINES FOR ASSESSMENT OF THERMAL PROTECTION

1. Introduction

In considering appropriate thermal protective equipment for use on ships operating in various climatic conditions, Adminis­trations and ship operators should take into account all of the relevant risk factors, to include type of ship, type of survival craft, number of persons on board, environmental conditions in the operational area, and availability of SAR services. The pur­pose of these guidelines is to provide information to assist in the assessment of the impact of environmental factors, and specifi­cally water temperature on equipment selection. In the context of the medical threat of hypothermia, the IMO publication "A Pocket Guide to Cold Water Survival" should be referred.

2. Thermal protective performance

In addition to the performance requirements specified in the LSA Code, there are some data available which illustrate the performance of the equipment at different water temperatures. Thermal protective performance for the various types of equip­ment at these temperatures is defined as the time to reach a deep body temperature of 35°C or reduce a deep body tempera­ture by 2°C, which is the point at which a significant degree of incapacitation is expected to occur. These data were obtained by a combination of