The Enhanced Survey Programme (ESP) is a comprehensive and systematic survey regime introduced by the International Maritime Organization (IMO) to ensure the continued structural integrity of ships throughout their service life. It involves more detailed inspections than normal statutory surveys and focuses particularly on detecting corrosion, structural deterioration, fatigue cracks, buckling and steel wastage before they become hazardous.

ESP requires close-up surveys, thickness measurements, detailed structural examinations and extensive documentation, thereby ensuring the vessel remains structurally fit for safe operation.

SOLAS Chapter Covering ESP

The Enhanced Survey Programme is mandatory under:

• SOLAS Chapter XI-1 – Special Measures to Enhance Maritime Safety
• Regulation 2 – Enhanced Surveys

The detailed survey requirements are contained in the IMO ESP Code (International Code on the Enhanced Programme of Inspections During Surveys of Bulk Carriers and Oil Tankers).

Applicability

Types of Vessels

ESP applies mainly to vessels subjected to high structural stresses and corrosive environments, including:

• Oil tankers
  • Single-hull and double-hull tankers
  • Oil/chemical tankers
  • FPSOs (where applicable)
• Bulk carriers
  • Single-side skin bulk carriers
  • Double-side skin bulk carriers
• Combination carriers (OBO carriers) and other ship types where required by the ESP Code.

When ESP Becomes Applicable

New Ships

• ESP requirements apply from the date of delivery.
• They are incorporated into the vessel's normal survey cycle, including:
  • Annual Surveys
  • Intermediate Surveys
  • Special (Renewal) Surveys

  Existing Ships

  • ESP becomes mandatory during the first applicable survey after the regulations came into force.
  • The inspections become progressively more extensive as the vessel ages, particularly from Special Survey No. 3 (approximately 15 years of age) onwards.
  Part (b)

  Procedural Method of ESP

  The ESP survey is carried out in a planned and systematic manner involving the ship's staff, Classification Society surveyor and an approved thickness measurement (TM) company.

  1. Survey Planning and Documentation

  • Review previous survey reports.
  • Examine thickness measurement records.
  • Check repair history and corrosion records.
  • Review coating condition reports.
  • Prepare a detailed Survey Programme jointly agreed between:
    • Ship owner
    • Classification Society
    • Thickness measurement company.

    2. Preparation of Spaces

    Before inspection, all spaces to be surveyed must be properly prepared.

    This includes:

    • Cleaning tanks and structures.
    • Removing mud, sludge, rust scale and oil deposits.
    • Gas-freeing enclosed spaces.
    • Providing adequate ventilation.
    • Arranging sufficient lighting.
    • Providing safe access using staging, rafts or hydraulic platforms.

    3. Close-up Survey and Visual Examination

    The attending surveyor carries out a detailed inspection of structural members for:

    • Corrosion
    • Pitting
    • Cracks
    • Buckling
    • Deformation
    • Fractures
    • Coating breakdown
    • Excessive steel wastage

    Special attention is given to areas known to suffer high stress or corrosion.

    4. Thickness Measurement (TM)

    Ultrasonic Thickness Measurement (UTM) is carried out by an approved company.

    Thickness measurements are taken on:

    • Deck plating
    • Bottom plating
    • Side shell
    • Bulkheads
    • Frames
    • Floors
    • Girders
    • Stringers
    • Other suspect structural members

    The measured values are compared with the original thickness and the allowable corrosion limits specified by the Classification Society.

    5. Evaluation and Reporting

    The surveyor evaluates:

    • Structural condition
    • Remaining plate thickness
    • Corrosion level
    • Need for repairs or steel renewal

    If satisfactory:

    • The Classification Society endorses or renews the vessel's Class.
    • Relevant statutory certificates (including Safety Construction Certificate) are renewed.
    Part (c)

    Engine Room ESP – Responsibilities of the Second Engineer

    Although ESP mainly focuses on the hull structure, cargo spaces and ballast tanks, the Second Engineer is responsible for preparing and presenting all engine room structural spaces that form part of the ship's hull.

    The following areas are normally presented during ESP:

    1. Double Bottom Tanks and Structures

    Prepare and present:

    • Engine room double-bottom ballast tanks
    • Fresh water tanks
    • Fuel oil double-bottom tanks (when included in the survey)

    The following structural members should be clean and accessible:

    • Floors
    • Centre girders
    • Side girders
    • Frames
    • Longitudinals
    • Tank-top (inner bottom) plating

    The surveyor will inspect for:

    • Corrosion
    • Pitting
    • Cracks
    • Buckling
    • Structural deformation

    2. Tank Top (Inner Bottom)

    The tank top beneath:

    • Main engine
    • Auxiliary engines
    • Boilers
    • Heavy machinery

    should be thoroughly cleaned.

    The surveyor checks for:

    • Oil contamination
    • Corrosion
    • Structural distortion
    • Cracks
    • Settlement around machinery foundations

    3. Engine Room Structural Bulkheads

    Present the following bulkheads:

    • Forward engine room bulkhead
    • Aft peak bulkhead (where applicable)
    • Engine room side bulkheads

    Inspection includes:

    • Stiffeners
    • Brackets
    • Web frames
    • Plating
    • Weld seams

    4. Shell Plating and Side Structures

    Present internal shell structures including:

    • Side shell plating
    • Side stringers
    • Web frames
    • Longitudinal stiffeners

    Special attention is paid to:

    • Sea chest areas
    • Bilge regions
    • Main engine seating areas

    where corrosion and fatigue are more likely.

    5. Main Engine Foundation

    The main engine seating is carefully inspected.

    Present:

    • Bedplate seating
    • Foundation girders
    • Chocks
    • Holding-down bolts
    • Side stoppers
    • Welded connections

    The surveyor checks for:

    • Cracks
    • Relative movement
    • Loose holding-down bolts
    • Distortion
    • Foundation settlement

    6. Auxiliary Engine and Generator Foundations

    Present the seating arrangements of:

    • Diesel generators
    • Auxiliary machinery
    • Compressors
    • Pumps

    Inspection includes checking for:

    • Fatigue cracks
    • Oil-induced corrosion
    • Loose foundation bolts
    • Structural deformation

    7. Sea Chests and Overboard Areas

    Where access is available, present:

    • Sea chest internals
    • Gratings
    • Shell connections
    • Corrosion protection arrangements
    • Overboard discharge structures

    These are examined for corrosion, coating condition and structural integrity.

    Second Engineer's Preparatory Actions Before ESP

    Before the survey, the Second Engineer should ensure that:

    • All designated double-bottom and machinery space tanks are thoroughly cleaned and mucked out.
    • Tanks are gas-freed, ventilated and certified safe for entry where required.
    • Adequate lighting and safe access (staging, ladders or rafts) are provided.
    • Bilges are clean and dry.
    • Structural members are free from oil, sludge and loose scale.
    • Thickness measurement locations are clearly accessible.
    • Previous ESP reports, thickness measurement records, repair records and structural drawings are available for the surveyor.
    • Safety equipment, communication arrangements and enclosed-space entry procedures are fully complied with during the survey.