Published: July 2018
This publication describes risk assessment and hazard identification techniques that can be applied by LPG/chemical gas shipping staff and terminal operators. It identifies the principal risks at the ship/shore interface, including vessel arrival and departure, loading and discharge operations, gas detection and exposure to hazardous products. Diagrams support the text and effectively illustrate how to mitigate ‘top event’ hazards to cargo containment.
Table of Contents
1. Hazards and Risk Management
1.1 Introduction
1.2 The ‘Bowtie Method’ of Risk Assessment and Management
1.3 Hazards, Threats and Barriers Identified
2. Operational Readiness
2.1 The Terminal
2.2 The Ship
3. Pre-Arrival
4. Arrival Alongside Prior to Cargo Operations Commencing
4.1 Pre-Cargo Operations Meeting
4.2 Safe Access
4.3 Emergency Procedures
4.4 Mooring
4.5 Simultaneous Operations (‘SimOps’)
5. Cargo Operations (General)
5.1 Cargo Emergency Shutdown (ESD) System and Ship/Shore Link (SSL)
5.2 Communications
5.3 Manifolds and Transfer Systems
5.4 Awareness of Surge Pressures
5.5 Gas Detection On Board an LPG Carrier
5.6 Gas Detection at the Terminal
5.7 Cargo Sampling
5.8 Cargo Monitoring Instruments – Checks Prior to and During Cargo Transfers
5.9 Warm Cargoes
5.10 Reliquefaction and Tank Pressure Management
5.11 Hydrates
5.12 Incondensibles
5.13 Cargo Equipment Temperature, Flow and Pressure Limitations
5.14 Manifold Connection
5.15 Insulating against Static Electricity
5.16 Vapour Return
6. Cargo Loading
6.1 Gassing-Up
6.2 Cooldown
6.3 Preliminary Procedures before Loading
6.4 Management of Tank Pressure During Loading
6.5 Commencement of Loading
6.6 The use of Automatic Shutdown during Topping Off
6.7 Operation of the Reliquefaction Plant during Bulk Loading of LPG
6.8 Cargo Tank Loading Limits
6.9 Odorisation of LPG
6.10 Inhibition
7. Cargo Discharge
7.1 Discharge Temperature and Pressure
7.2 Blending at the Terminal
8. LPG Carrier Departure
8.1 Manifold Draining, Purging and Disconnection Procedure
8.2 Disconnection
8.3 Preparation Prior to Unmooring
9. Release of Vapour
10. Cold Spill
11. Asphyxiation and Toxicity
Annexes and Back Up Data
Annex A – Competencies & Training
Annex B – Properties of Chemical and Liquefied Petroleum Gases
Annex C – LPG/Chemical Ship Types
Annex D – Bowtie Diagrams
