On board, crew members often have to work in enclosed areas (safes, bunkers). To enter an enclosed space, tests must be carried out to determine if the enclosed space is safe to enter. Respiratory hazards from certain sources may be contained in enclosed spaces such as hydrocarbon vapor, hypoxia, toxins such as benzene, sulphuahydro that may remain in space due to the scum of various goods.
There have been many risks of fatality in enclosed spaces of oil tankers due to entering enclosed spaces without supervision or non-compliance with the agreed process.
In most of these cases, death can be avoided if following the simple instructions below. It is especially dangerous to quickly save people from collapsing in enclosed spaces. The natural human response is to support colleagues in times of difficulty, but too many deaths are not necessary in attempts to save people and poor preparation.
1. Overview of enclosed spaces:
Enclosed space is a space with a narrow entrance that is not regularly ventilated, and the atmosphere in it can be dangerous because of the presence of hydrocarbon gases, toxic gases, inert gases or lack of oxygen. Enclosed spaces include safes, ballasts, fuel tanks, water tanks, lubricant safes, oil and waste oil deposit tanks, toilet water tanks, isolation tanks, living bottoms, empty spaces and compartments, pipes or fittings connected to one of the above spaces , which also includes the filter and water sealer of the inert gas system and other items of the machine and equipment that are not ventilated and enter regularly such as boilers and main machine cac-te.
|Some limited space on the oil tanker|
2. Test the atmosphere before entering enclosed spaces :
It is only decided to go into enclosed spaces after having tested the atmosphere in the safe as a total from the outside to the inside with new test devices(gas detectors)that are tested and operated correctly.
It is important for the device used to try out the atmosphere is:
- Suitable for test requirements
- It’s an acceptable type.
- Properly maintained
- Regularly checked for comparison with standard samples
Care must be taken to maintain the representative cross section of a cavity by sampling at different depths and through as many measuring holes in the deck as possible. When conducting a test at the main deck level, ventilation must stop and at least after 10 minutes to be measured.
Testing must be conducted immediately before the start of work or after the work is interrupted or discontinued. Sufficient sampling is required to ensure that the measured results represent the state of both enclosed spaces entering.
3. Conditions for entering enclosed spaces:
Permits for access to enclosed spaces must be issued by the Officer responsible for issuance before allowing people into enclosed spaces.
Appropriate attention must be clearly in place to guide people on what precautions to take when entering enclosed spaces and all restrictions placed on work in that enclosed space.
Permission to enter enclosed spaces will be void when ventilation for such enclosed space is discontinued or if any of the conditions stated in the check list are changed differently.
|Permits to enter restricted spaces on oil tankers|
4. Process of entering enclosed spaces:
No one can enter enclosed spaces unless permits to enclosed spaces are issued by responsible officers. Before issuance of licenses into enclosed spaces, officers are responsible for ensuring that:
- Appropriate tests have been carried out for the atmosphere: oxygen volume content is 21%, hydrocarbon concentrations are not more than 1% of the fire limit under the LFL (Lower flammable limit) and there are no toxic gases or other dirt.
- Effective ventilation must be maintained continuously while at work.
- A rescue cord and straps must be ready to use immediately and leave at the entrance to the enclosed space.
- Breathing equipment with positive pressure is accepted and emergency resuscitation equipment must be ready for immediate use and placed at the entrance to enclosed spaces.
- If possible, another entrance must be prepared for alternative use in case of emergency.
- A crew member is responsible for standing at the entrance to the enclosed space and contacting the responsible officer directly. The lines of communication to deal with emergencies must be clearly established and everyone involved must understand.
5. Respiratory protection equipment:
- Breathing equipment with pneumatic water: This device consists of one or more pneumatic cans attached to a frame and a strap for the user. Air supplies to the user through an adjustable respirator and ensures airtightness. A gas pressure indicators clock in the air and a siren when the gas supply is low.
- Breathing devices with air duc ducs: Breathing devices with air ductils allow for longer compressed air use than those with available compressed air. This device consists of a respirator that is supplied with air through a small diameter hose, which is led out into enclosed space and connected to a compressed air can or an air compressor. If using the vessel’s compressed air source, it is important that compressed air be filtered appropriately and closely monitored for toxic and dangerous components.
- Mask with air filter cartridge: This mask consists of a small box connected to the mask, which is designed to filter the air of a specific poison. These devices do not protect the user against hydrocarbon vapor or toxic vapor when there is an excessive concentration of the design, or when there is a lack of oxygen, and should not be used instead of breathing equipment.
- Air hose respirator (breathing device with clean air): This device consists of a respirator that is supplied with air by a large-diameter pipe connected to a propeller pump or a blower. This device is bulky and has no gaskets against the penetration of gas. Although this device can be seen on some ships, it is recommended that it not be used for entering enclosed spaces.
6. Warning when entering enclosed/or semi-enclosed areas:
- Do not enter a safe or a closed vault for a while, even if it does not contain toxic substances. First ventilate and take measures to check measurements without gas or toxic gases and at the same time have the necessary amount of oxygen.
- In the course of performing work, it is necessary to regularly inspect the measurement. (Reference for using gas detection machines for seagoing vessels)
- The space in the safe and enclosed area must be considered toxic until the measuring device says it is completely safe to enter. Areas other than this type are only allowed when ordered by the officer in charge. If you are not sure that the space is non-toxic, you must use a protective device.
- Two help people must be arranged outside the safe or cellar for relief and rescue. We need to negotiate a signal to communicate with each other first.
- Use approved work protection, seat belts and signal wires.
- Ensure that the shift officer has been notified and keeps in touch with him throughout the course of his work. Place the smoke cannon next to it to be ready to use.
- If the incident occurs one of the helpers must quickly press the siren and the other person lights the smoke cannon and begins the rescue action. The urgent task is to provide air to the victim and give him a ventilated area.
- • Accidents in safes and in vaults have toxic environments, so quick requests for rescue organizations come first.
7. Working in enclosed spaces:
- Before carrying out work, it is necessary to check to ensure that there are no residues, dirt or burning materials around, these substances if stirred or heated can release toxic gases or flammable gases. Effective ventilation is maintained, and if possible, pointed directly at the work area.
- Whenever the pump is removed, pipes, valves or drying rigs, it must first be through water. However, even if it is through water, there may still be some leftovers and then it is possible to give birth to flammable or toxic gases. Therefore, additional gas testing work must be carried out when removing these devices.
- Work tools must be contained in a tarpaulin bag and dropped to prevent the tool from falling causing sparks.
- Unacceptable lights or unsafe electrical equipment are not allowed in enclosed spaces
- Gas testing and continuous ventilation must be carried out throughout the work of removing sludge from enclosed spaces. It is necessary to equip personal gas detection equipment for those involved in this work.
- When conducting cold work in enclosed spaces, in addition to the satisfying atmosphere, it is also necessary to be granted a work permit. It is also necessary to remove all the mud deposits away from the workplace. When conducting cold work in enclosed spaces while the ship is docking, it is also necessary to consult the representative of the wharf because it may require permission from the wharf.
- In order to be able to carry out hot work in enclosed spaces, it is only possible to do it when all safety regulations have been applied and all safety requirements are satisfied and a permit for hot work has been issued.
- Boats working in enclosed spaces must be inflatable boats that are built intendively and are acceptable. Working boats are only used in clean ballast water tanks, the water level in the safe must be either stationnable or decreasing; do not have water level in the safe for any reason while using the canoe in the safe. Everyone working on the canoe must wear a personal life jacket.
8. Rescue action:
- Press the fire alarm to alert the entire crew, and announce on the loudspeaker where the rescue action is proceeding.
- The fire retardant team gathers firefighting equipment and is ready. Rescuers must wear their own rescue equipment as quickly as possible before arriving at the crash site.
- The Engineering Team uses existing equipment to provide light and attempt ventilation in the accident site;
- The two rescuers wore the equipment and re-examined their gas canes. The incident light machine must be ready. The rescuers were tied to the rescue cord and the captain re-examined the pressure of the comment and calculated the time of the rescue action.
- Two lifes rescuers with seat belts entered the crash area and each had a helper to loosen the cord appropriately and ensure safety. Backup equipment must be brought down as soon as the Rescuer descends to the bottom of the safe, cellar. Other rescuers must be ready to act. Lifting equipment with a raised frame is prepared and man-controlled
- When the victim is found, see if on-site treatment is required or must be removed from the safe. Do not be indifferent even the smallest to the injured. Do not waste time on stretcher and take the injured to the crane position and put on the crane frame. If more than one person is injured, priority is given to those near the lifting equipment location. Tie the rope firmly to the injured during the lifting process. If the transport is too difficult, send more rescuers to assist.
- A signaler above instructs the others in the process of pulling up. If more people are injured, additional rescuers must be arranged in the safe to assist with the transportation.
- A stretcher must be ready for further transportation after first aid. Remember the first aid rule: Ventilated – Loosened – Respiratory – Heartbeat and procedures for resuscitation.
9. The following equipment must be available for rescue action:
- Breathing protection device with oxygen bottle. Filter masks are used only in cases where the appropriate amount of oxygen is accurately measured.
- Gas protection vests, if intended to be used, will prevent chemicals from appearing to harm the skin.
- Helmets with chin fastenings, gloves with a large surface friction to increase grip.
- Anti-slip boots.
- The seat belts, at least two, are durable, with many hook defects to protect those who climb down.
- Handheld fans for ventilation in hazardous areas.
- Stretchers are equipped with hanging wires and hooks for cranes, at least two with many hook defects.
- The crane frame is equipped with bearing shoulders and fastenings, or safety frames.
- Heat, oil, water and explosion-resistant flashlights
- Oxygen tank for the wave man.
- First aid equipment for initial treatment of the saved person.
- Stretcher for transport after first aid.
Only after the actual practice can we decide what kind of equipment is needed for each vessel.
When an accident involving human casualties occurs in enclosed spaces, the first thing is to ring the alarm. While speed is often a matter of life-saving, emergency operations are not attempted when the necessary equipment and assistance are not fully concentrated. There are many examples of loss of life due to attraction, trying to save lives while not fully prepared.
Organizing from the beginning is of great value in quick and effective response. Life-saving wires, breathing equipment, resuscitation equipment and other emergency equipment must always be ready to use and a trained emergency crew is required. signals rules must be agreed in advance.
Emergency officers must always be outside the area where the most effective control can be carried out.
Most importantly, each member of the emergency team must know what can happen and regularly conduct emergency training out of enclosed spaces.