Styrene monomer, stabilized

When materials are stabilized by temperature control, the provisions of § 173.21(f) of this subchapter apply. When chemical stabilization is employed, the person offering the material for transport shall ensure that the level of stabilization is sufficient to prevent the material as packaged from dangerous polymerization at 50 °C (122 °F). If chemical stabilization becomes ineffective at lower temperatures within the anticipated duration of transport, temperature control is required in which case transportation is forbidden by aircraft. In making this determination factors to be taken into consideration include, but are not limited to, the capacity and geometry of the packaging and the effect of any insulation present; the temperature of the material when offered for transport; the duration of the journey and the ambient temperature conditions typically encountered in the journey (considering also the season of year); the effectiveness and other properties of the stabilizer employed; applicable operational controls imposed by regulation (<i>e.g.,</i> requirements to protect from sources of heat, including other cargo carried at a temperature above ambient); and any other relevant factors.

Browse special provision 387

If the material has a flash point at or above 38 °C (100 °F) and below 93 °C (200 °F), then the bulk packaging requirements of § 173.241 of this subchapter are applicable. If the material has a flash point of less than 38 °C (100 °F), then the bulk packaging requirements of § 173.242 of this subchapter are applicable.

Browse special provision B1

_{Authorized IBCs:} Metal (31A, 31B and 31N); Rigid plastics (31H1 and 31H2); Composite (31HZ1 and 31HA2, 31HB2, 31HN2, 31HD2 and 31HH2).<br>_{Additional Requirement:} Only liquids with a vapor pressure less than or equal to 110 kPa at 50 °C (1.1 bar at 122 °F), or 130 kPa at 55 °C (1.3 bar at 131 °F) are authorized, except for UN2672 (also see special provision IP8 in Table 2 for UN2672).

Browse special provision IB3

<table class="table table-bordered table-condensed ushmr-sp-table"><tr><th>Minimum test pressure (bar)</th><td>1.5</td></tr><tr><th>Minimum shell thickness</th><td>§ 178.274(d)(2)</td></tr><tr><th>Pressure-relief requirements</th><td>Normal</td></tr><tr><th>Bottom opening requirements</th><td>§ 178.275(d)(3)</td></tr></table>

Browse special provision T2

The maximum degree of filling must not exceed the degree of filling determined by the following:<br><br>Where: <br>t_r is the maximum mean bulk temperature during transport, and t_f is the temperature in degrees celsius of the liquid during filling.

Browse special provision TP1

C

Stowage category “C” means the material must be stowed “on deck only” on a cargo vessel or on a passenger vessel.

Source: 49 CFR §172.101(k)