Occupational Hygiene

Client

Rio Tinto Marine

Description of the project

SHE Monitoring Programme

Rio Tinto Marine own and charter a number of bulk cargo vessels to carry bauxite cargos from Weipa on the west coast of the York Peninsula in far north Queensland to the alumina refineries in Gladstone. Rio Tinto policies require periodical OHS exposure assessments to be conducted for all Similarly Exposed Groups (SEGs) and work sites.

This commission involved the design and implementation of a detailed safety, health and environment (SHE) monitoring programme on seven ships owned and chartered by Rio Tinto Marine.
The ships included in this SHE monitoring programme included four coal fired steamships and three marine diesel motor ships. The SHE monitoring programme was developed and implemented in accordance with the protocols outlined in the Rio Tinto Marine (RTM) Occupational Health Exposure Monitoring Programme.

The project involved occupational and environmental assessments of 17 key subject areas. The subject areas and the primary objectives of the study for each area are as follows:

  • Occupational Noise:

    • determine representative noise exposure for personnel within the various SEGs over the work shift and 24 hour periods;
    • identify and/or confirm noise classification, i.e. areas >83 dB(A) and to review placement of hearing protection warning signs;
    • determine compliance with IMO A.468 for low noise areas; and
    • determine / confirm suitability of hearing protection devices (HPDs).

  • Occupational Vibration:

    • To assess the risk of exposure to occupational vibration on board the vessel with respect to whole body vibration (WBV) and hand arm vibration (HAV).

  • Shipboard Chemicals, the primary objectives were to:

    • Identify hazardous substances (HS)/dangerous goods (DG) on-board,
    • Compile a HS/DG Register,
    • Review the currency, availability and appropriateness of Material Safety Data Sheets (MSDS), and
    • Review the overall management of HS/DG.
  • Hydrocarbon Liquid, Mist, Particulate and Vapour:
    • characterise the engine room air quality to determine the hydrocarbon ‘fingerprint’ for hydrocarbon exposures in the primary exposure areas;
    • conduct an initial quantitative risk assessment of volatile contaminant exposures from which further investigations will be planned; and
    • determine the contribution of skin contamination to exposure risk.
  • Cargo Dust:
    • confirm the crystalline silica and titanium dioxide (TiO2) content of the grades of bauxite carried by the vessels of the QAL fleet; and
    • determine the potential exposure of the vessel crew to airborne dust during cargo operations.
  • Welding Assessment
    • to determine the risk associated with welding process on-board and to review controls as appropriate.
  • Extraction & Ventilation Systems
    • review the adequacy of fresh air and/or extraction/ventilation systems in the engine room, in order to minimise exposure to airborne contaminants, and
    • identify and confirm any hot work areas in the engine room.
  • Respiratory Protection Programme
    • identify the likely sources of respiratory hazards on board from observations, hazardous substances review, and air monitoring results obtained,
    • evaluate the needs for respiratory protection, and
    • make recommendations as appropriate.
  • Thermal Stress Management
    • identify and quantify risks associated with heat exposure for personnel, and to review controls as appropriate.
  • Ionising and Non-Ionising Radiation
    • identify sources of ionising and non-ionising radiation on board the vessels and to determine what risk these sources may impart to the ship’s crew.
  • Asbestos & Other Fibrous Silicates
    • Determine suitability and currency of the vessels’ asbestos register.
  • Engine Room Dust
    • determine the inhalable and respirable dust levels in the engine rooms;
    • determine the potential health implications the dust may impart to the ship’s crew;
    • review controls as appropriate.
  • Manual Handling
    • determine if any significant manual handling issues exist on board the various vessels;
    • to determine if appropriate procedures exist, and to review controls as appropriate.
  • Confined Spaces
    • observe current work practices and procedures, and the work environment during confined space work;
    • review relevant documented records/procedures for suitability and currency;
    • review controls as appropriate.
  • Height Safety
    • observe current practices as they presented themselves, and to note issues of concern;
    • discuss with ship personnel concerns/issues they may have with respect to working at heights; and
    • review relevant documentation e.g., safe work method statements (SWMS) or similar and training records if available.
  • Biological Hazards
    • Reviewing illness records;
    • conducting airborne bacteria, yeasts and moulds biological air monitoring in operational and living quarters;
    • conducting a visual assessment of floor coverings, bulkhead lining spaces;
    • analysing a representative sample of sewage post treatment, and
    • reviewing controls as appropriate.
  • Food & Water Quality
    The primary objectives were to assess the ships against the general principle of a Hazard Analysis and Critical Control Point (HACCP) methodology, and relevant Australian/NZ Food Standards/Codes. As part of this assessment, the following was conducted:
    • a review of ship illness records;
    • critical temperature measurements of the cold/hot food chain;
    • a review ship records of high and low temperatures representative of routine (daily) checks, wherever available;
    • observation of food safety practices and general hygiene including food storage and preparation techniques in the galley;
    • assessing galley personnel have been appropriately vaccinated; and
    • assessment of drinking water quality

Data Quality Objectives (DQOs) were developed for each phase of the project to ensure (i) compliance with relevant sections of the RTM OHS management plan and (ii) that the type, quantity, and quality of data used in decision making were appropriate for the intended application.

The DQOs considered the following parameters for each phase and module of the study:

  • Design criteria for each phase of the study;
  • Statistical considerations:
  • size of the target population and selection of Similarly Exposed Groups (SEGs);
  • selection of candidates for exposure assessment, dosimetry and physiological measurements;
  • statistical requirements for interpretation of the data collected;
  • Use of appropriately trained and experienced personnel for the study design, sample collection, analysis and interpretation of the results;
  • Selection of appropriate methods and equipment for collection of samples:
    • suitability of sampling equipment (portable, reliable, stable and robust);
    • sample collection media;
    • analytical requirements;
    • sample storage: stability, light sensitivity, preservation (e.g. treatment and/or refrigeration), holding times, etc.;
    • calibration status and requirements for field calibration;
  • Selection of appropriate instrumentation for measurement of required parameters:
  • suitability of instrumentation (portable, reliable, measurement parameters and range, stable and robust);
  • calibration status and requirements for field calibration;
  • Analytical requirements for samples:
  • collection media and techniques for air and water samples;
  • use of NATA Accredited laboratories, where available;
  • Record keeping and traceability (Chain of Custody documentation) for field data;
  • Interpretation of the data:
  • application of suitable Occupational Exposure Limits;
  • statistical analysis of the data;

Details of any innovations on these projects

During cargo discharge, small quantities of bauxite lost from the grabs accumulate on the hatch covers and exposed areas of deck on the port side of the vessels. The bauxite pisolites, which are approximately spherical in shape, present a significant slip hazard on the steel decks and hatch covers.
At the completion of the discharge, the material accumulated on the hatch covers is pushed (by broom of hose) back into the holds. The hold side of the hatch cover is an exposed edge with an 18 metre drop to the floor of the hold. On some vessels there is no travel restraint for fall arrest system on the hatch cover. The procedures were amended so that the hatch covers were closed (leaving a 10 cm gap) before being accessed for cleaning where fall protection (barriers, travel restraint or fall arrest) cannot be provided.

During the course of the commission, indoor air quality issues became apparent on the Weipa class vessels. Water is driven off (by heating) the waste oil tank vents to the mist box on the aft face of the funnel.
The material discharging from the mist box is highly visible due to the high level of water vapour and has a strong odour of fuel oil. The fresh air intake for the air-conditioning system is on the same deck adjacent to the funnel. Under certain environmental conditions, the vapours and fumes from the mist box are entrained into the AC fresh air intake.

As the entrainment of fumes and vapour into the air-conditioning system are episodic phenomena dependent on the prevailing winds, air quality monitoring within the accommodation is problematic. Two novel, cost effective solutions were identified to resolve this issue:

  1. Extend the waste oil tank vent so that it discharges at the top of the funnel. The vent line would need to be insulated to maintain the flue gas temperature above the dew point. Increasing the temperature of the waste oil tank would also be required to assist with maintaining optimum flue gas temperatures.
  2. The AC fresh air trunk is located on the starboard sidewall of the accommodation and drops several decks to the AC fan room below. Accordingly, existing fresh air intake could be closed and additional grilles installed on the side of the accommodation (two decks below the funnel) and the same area of intake opening could be achieved, while maintaining adequate clearance above the water line.

Activities that provided value added options to the client, detailing any long term benefits

  • The project produced a substantial amount of exposure data, statistical evaluation of which is being used by RTM to manage chemical and physical exposures in various SEGs.
  • Instruction provided to various ships’ officers with respect to greater/better use of the ships’ Chemical Data Base system. Long term benefits include easier tracking of shipboard chemicals inventories, MSDSs and storage of dangerous goods. Recommendations with respect to greater and better use of the data base were also supplied in the reports to the client.