Page 189 - Challenges in Corrosion Costs Causes Consequences and Control(2015)

HAZARDOUS MATERIALS TRANSPORT 167

To accommodate the properties of the cargo, in addition to the use of coatings and
linings, certain components of the cars, such as valves, undergo an upgrade from the
lower-resistant carbon steel to the higher resistant steel grades, such as stainless steel.
Rubber linings are used for strong acids (concentrated hydrochloric and phospho-
ric acid). For extremely aggressive concentrated nitric acid, the entire tank car body
is made from stainless steel (316L).

3.21 HAZARDOUS MATERIALS TRANSPORT

This sector includes the transportation of hazardous materials (HAZMAT) other than
that of the transportation of hazardous gases and liquids by buried pipelines.
Bulk transportation of HAZMAT involves overland shipping by tanker truck and
rail tank car and by specialized containers that are loaded onto vehicles. Over water,
ships loaded with specialized containers, tanks, and drums are used. In small quanti-
ties, HAZMAT requires specially designed packaging for truck and air shipments.
Trucks are used for the transportation of hazardous materials. Stainless steel tanks
are used in highway trucks. Storage drums and a corroded storage drum are shown in
Figure 3.26.
Hazard classifications assigned for distinct HAZMAT are listed in Table 3.9.
Class 5 and 8 materials require shipping and storage containers that are resistant
to corrosion to prevent internal damage. Most of the materials cited in class 1–9 can
become corrosive to mild steel containers when contaminated with moisture. Depend-
ing on the environment, materials from all categories must be shipped and stored in
containers that are protected from external corrosion damage.
The daily and annual number of HAZMAT shipments is listed in Table 3.10.
The Research and Special Programs Administration (RSPA) of the US Depart-
ment of Transportation (DOT) published a list of the top 50 hazardous materials in a
1998–1999 summary of HAZMAT transportation incidents (24). The corrosive mate-
rials that were most involved in HAZMAT incidents in 1998 were sodium hydroxide
solutions, basic inorganic liquids, hydrochloric acid, solutions, sulfuric acid, clean-
ing liquids, hypochlorite solutions, basic organic liquids, liquid amines, and ammonia
solutions.
Table 3.11 shows hazardous materials carried by trucks as reported in VIUS.
Shippers are required to report HAZMAT incidents to the US DOT whenever there
is an unintentional release of a HAZMAT. The information from all submitted forms
is collected in the Hazardous Materials Information System (HMIS) incident data
base, which is maintained by RSPA and includes data reported by carriers for the
past 30 years. The following data shows the number of, as well as the consequences
resulting from, serious incidents. In 1998, there were roughly 15,000 reported HAZ-
MAT incidents related to HAZMAT shipments resulting in 13 deaths and 198 injuries.
On DOT Form 5800.1 shippers are required to give a description of the packaging
failure for each incident. Corrosion is also a contributing factor for the packaging
failure.