UN 1977 Nitrogen, refrigerated liquid ADN 2025 (Shortinfo)

For each member of the crew, a pair of protective goggles, a pair of protective gloves, a protective suit and a suitable pair of protective shoes (or protective boots, if necessary). On bord tank vessels, protective boots are required in all cases.

When these substances are carried, the vessel shall be equipped with a quick closing valve placed directly on the shore connection.

(a) The joints, outlets, closing devices and other technical equipment shall be of such a sort that there cannot be any leakage of refrigerated liquefied gases during normal transport operations (cold, fracturing of materials, freezing of fixtures, run-off outlets etc.). (b) The loading temperature (at the loading station) shall be mentioned in the transport document. (c) An oxygen meter shall be kept on board, together with instructions on its use which can be read by everyone on board. The oxygen meter shall be used as a testing device when entering holds, pump rooms, areas situated at depth and when work is being carried out on board. (d) At the entry of accommodation and in other places where the crew may spend time there shall be a measuring device which lets off an alarm when the oxygen level is too low. (e) The loading temperature (established after loading) and the maximum duration of the journey shall be mentioned in the transport document.

Loading of refrigerated liquefied gases shall be carried out in such a manner as to ensure that unsatisfactory temperature gradients do not occur in any cargo tank, piping or other ancillary equipment. When determining the holding time (as described in 7.2.4.16.17), it shall be assured that the degree of filling does not exceed 98% in order to prevent the safety valves from opening when the tank is in liquid full condition. When refrigerated liquefied gases are carried using a system according to 9.3.1.24.1 (b) or 9.3.1.24.1 (c), a refrigeration system is not required. In the case of UN No. 2187 'CARBON DIOXIDE, REFRIGERATED LIQUID', this provision applies when the possibility of solidification shall be avoided. To ensure the product remains in the liquid phase, the temperature shall be kept at 15 °C above the solidification temperature at the required pressure during the transport. The transport document shall contain a notice on the avoidance of solidification of the product.

Materials of construction and ancillary equipment such as insulation shall be resistant to the effects of high oxygen concentrations caused by condensation and enrichment at the low temperatures attained in parts of the cargo system. Due consideration shall be given to ventilation in areas where condensation might occur, to avoid the stratification of oxygen-enriched atmosphere.