Page 46 - International safety guide for oil tankers and terminals

INTERNATIONAL SAFETY GUIDE FOR OIL TANKERS AND TERMINALS

or surveyors whether the previous cargo contained any toxic substances. (See
Section 26.3.3 – Ship/Shore Safety Check-List, Item 26.)
hydrocarbons.รศึกษาเท่านั้น---
Provision of an MSDS does not guarantee that all of the hazardous or toxic
components of the particular cargo or bunkers being loaded have been
งานห้องสมุด ศูนย์ฝกพาณิชย์นาวี
identified or documented. Absence of an MSDS should not be taken to
indicate the absence of hazardous or toxic components. Operators should
have procedures in place to determine whether any toxic components are
present in cargoes that they anticipate may contain them.

2.3.5 Benzene and Other Aromatic Hydrocarbons

2.3.5.1 Aromatic Hydrocarbons
The aromatic hydrocarbons include benzene, toluene and xylene. These
substances are components, in varying amounts, in many petroleum
cargoes such as gasolines, gasoline blending components, reformates,
naphthas, special boiling point solvents, turpentine substitute, white spirits
and crude oil.

With the excepion of benzene (see Section 2.3.5.2), the health hazards of
aromatic hydrocarbons are not fully established, but it is recommended
that personnel engaged in cargo operations involving products containing
ึ
them follow the precautions and procedures described in Sections
---ใช้เพื่อกา
11.1.6.6 (Closed Loading) and 11.8.4 (Measuring and Sampling) in order
to minimise exposure due to cargo handling operations. The TLV of an
aromatic hydrocarbon vapour is generally less than that of other

The supplier should advise the tanker of the aromatic hydrocarbon
content of the cargo to be loaded (see Section 2.3.4 above).

2.3.5.2 Benzene

Exposure to concentrations of benzene vapours of only a few parts
per million in air may affect bone marrow and may cause anaemia
and leukaemia.

IMO has established minimum standards for ships carrying liquids in bulk
with a benzene content of 0.5% or more. (See Bibliography for ‘Revised
Minimum Safety Standards for Ships Carrying Liquids in Bulk Containing
Benzene’.) They cover requirements for the transfer of information on the
cargo by MSDS, occupational exposure limits, air quality monitoring,
personal protective equipment and its maintenance, medical monitoring,
and precautions during cargo operations. There is some crossover
between cargoes containing benzene in MARPOL Annex I and some of
the precautions to be followed as defined by MARPOL Annex II and the
associated IBC and BCH Codes.

The following guidance uses the operational exposure limits in the IMO
standards and provides general advice on precautions to be adopted by
oil tankers carrying cargoes containing benzene at lesser concentrations.

Benzene primarily presents an inhalation hazard. It has poor warning
qualities as its odour threshold is well above the TLV-TWA.

12 © ICS/OCIMF/IAPH 2006