Burning and welding are among activities most likely to produce fire on board. Many fire incidents have resulted from the ignition of combustible materials or the ignition of structures or debris near the hot work area. However, these activities can be performed safely, if proper precautions are taken both before and during such work.
A basic precaution is that no work involving burning, welding or other spark igniting activity shall begin until authorized by Master.
Authorization
Authorization is the number one issue before starting. In that regard, a permit to work should be issued for welding and flame cutting operations elsewhere than in the workshop. Note that a workshop onboard is the dedicated place for such works. Any other place requires specific time framed permit.
Authorization is to be granted by Master only after, Master / Chief Engineer or a responsible person delegated by them that has personally inspected the area in which work is to be done; has determined that it is safe to proceed and; has been assured that there is a thorough understanding of work to be accomplished and of the operational conditions.
When requesting authorization to carry out hot work, the following must be considered:
- each job must be subject of a separate request
- each request must give sufficient details of actual hot work involved for job to be properly assessed
- each request must confirm that precautions required have been complied with
- each request must give anticipated start and finishing times of job
A hot work authority will normally remain valid for not more than 24 hours. After this period, an extension of authorization must be requested, confirming status of job commenced and precautions taken. Jobs must not start until authorization has been received. Moreover, before any similar task, a Toolbox Meeting should always be conducted.
Crew should be competent in process familiar with equipment to be used and instructed where special precautions need to be taken. Special care should be taken when welding or flame cutting in dangerous spaces to provide adequate ventilation since oxygen can be depleted by harmful fumes and noxious gases. In confined spaces, breathing apparatus may be required.
Fire Watch
Burning or welding shall not be performed by a person working alone. Chief Officer in cooperation with Chief Engineer shall delegate as many persons as necessary to act as a “fire watch” with specific instructions to observe flying sparks and falling slag in order to recognise and prevent possible fire hazards. Persons assigned to “fire watch” shall have no other duties while so employed.
Person in charge of operation shall be particularly alerted to assignment of an additional “fire watch” on opposite side of any bulkhead, deck or overhead subjected to burning or welding. “Fire watch” shall be equipped with a fire extinguisher and/or a running water hose when practical. Person in charge should establish a prearranged means of signaling, whereby burning or welding should cease immediately when a hazardous situation arises. Additional dry powder fire extinguishers may be located at working site.
Protective Clothing
Protective clothing should be worn by operator to provide protection from particles of hot metal slag and from accidental burns and their eyes and skin from ultraviolet and heat radiation.
Operator should normally wear:
- welding helmet with suitably colored transparent eye piece; eye goggles or hand-held shield may be suitable alternatives in appropriate circumstances
- leather working gloves
- leather apron
- long-sleeved natural fibre boiler suit or other approved protective clothing
- Clothing should be free of grease and oil and other flammable substances.
Precautions against Fire and Explosions
Before welding or flame cutting is to begin, a check should be made (especially from Chief Officer) in order to ensure that there are no combustible solids, liquids or gases at, below or adjacent to the area of work, which might be ignited by heat or sparks from the work.
Welding or other hot work should never be undertaken on surfaces covered with grease, oil or other flammable or combustible substances. All sludge, scale and sediment must be removed from an area of at least 10 meters around area of hot work. Other areas that may be affected by hot work should also be cleaned, e.g. area just below place where hot work is being undertaken. Local cleaning of areas where work is to be carried out, in order to make them safe for hot work, should not be done by using solvents of any kind.
Where work is being done close to or at bulkheads, decks or deckheads, remote sides of divisions should be checked for materials and substances which might ignite, and for cables, pipelines, or other services which may be affected by heat. Hot work on pipelines should only be permitted when appropriate section has been detached from system by cold work and open-ended sections of remaining system have been sealed off.
Fuel tanks, cargo holds or other tanks or spaces that have contained flammable substances should be certified as being free of flammable gases before any repair work is commenced. Area will be well ventilated throughout work period and periodic testing will be carried out to check that no concentrations of flammable or toxic gases develop. Welding and flame cutting operations should be properly supervised and kept under regular observation.
Record Keeping
Use of relevant Hot Work Permit Form should be always considered. After completion of work relevant checklist should be kept at file as required. Hot/cold work will never be without its risks, but these risks can be managed. With proper training, the correct tools and reliable equipment, the chances of a serious incident or accident occurring can be significantly reduced. By using the correct permit to work system and documentation, the protection of all those involved on board in such task will be increased and the relevant risk will be mitigated.