Hot work in shipyards is often performed in enclosed spaces that may expose workers to hazards. Workers performing hot work or working in spaces adjacent to hot work are exposed to the following risks: fire and explosions caused by flammable or combustible materials or airborne gases, vapors, and particulates; toxic gases and metal fumes produced from the hot operations (such as nitrogen oxides, and lead fumes); and ultraviolet radiation from electric arcs.
Before beginning hot work, the following tasks must be performed:
- Review the marine chemist certificate and shipyard competent person inspection record. If hot work permits are available, they should be reviewed.
- Ensure that the hot work surface is free of flammable and combustible materials.
- Maintain good housekeeping conditions.
- Ensure the availability of adequate fire watches.
- Inspect welding and cutting equipment before use (e.g., for arc or gas welding/burning).
- Perform a leak test on gas torches, gauges, and hoses.
- Use appropriate personal protective equipment (PPE) for the welder, burner, and other exposed employees.
- Provide UV shielding for arc welding where practical.
- Remove electrodes from electrode holder when not in use.
When hot work is being performed, it is also the employers' responsibility to ensure that precautions are taken in adjacent spaces.
The work space is initially inspected by a Certified Marine Chemist or a Shipyard Competent Person (SCP). Conditions may change during work, so the SCP must inspect the hot work area as often as necessary. If the SCP discovers a change that could adversely alter safe conditions (such as a missing fire watch, ventilation failure, piping system leak, or hazardous materials spill), work must be stopped. Work may not be resumed until the affected space is visually inspected and re-evaluated (by a Marine Chemist, if a marine chemist certificate was issued) to meet requirements.
Examples of items that can change conditions include:
- Temperature changes: increased or decreased temperatures affect flammable and toxic vapor levels.
- Type of work in tank: leaking torches, use of cleaning solvents, and removal of tank residue ("mucking out") may alter atmosphere.
- Unattended tanks or spaces: if a period of time has elapsed, it is recommended that spaces be retested before re-entry and continuation of work.
- Ballasting or trimming: changing the position of the vessel could release hazardous materials into a space or compartment.
- Ventilation changes: ventilation duct damage or fans not in use.
The Safety and Health Advisory Committee (SHAC) recommends that tests before re-entry and continuation of work in unattended tanks and spaces should be conducted at the beginning of the shift and then at least every 24 hours between tests.
For more information on shipyard employment safety, see this OSHA Shipyard Employment eTool for reference.