Confined Space Working Procedure

Working in a confined space can be very dangerous if you are unaware of the types of potential danger that dwell in a confined space. Before we discuss on the danger, perhaps it will be very beneficial to identify what is a confined space.

A confined space is
  1. Any workspace which is not meant/design for human occupancy.
  2. Any workplace where there are limit to the natural lighting.
  3. Any workplace where the source of ventilation is compromised.
  4. Any workplace where the point of exit is limited & the movement out of the workplace required restricted body movement.
Now, since you had identify that your workplace is a confined space, what are the items that you might want to focus on?
  1. The workplace might face Oxygen deficient or enriched. (Typical oxygen level is between 19.5% - 23.5%)
  2. Any release of flammable or toxic gas from the workplace? (e.g: methane, sulphur dioxide)
  3. Sufficient ventilation in the confined space?
  4. How many workers are allowed in the confined space? (This question could be very tricky)
  5. Which type of lighting is allowed?
Knowing the potential problems, it's now to tackle them. How?
  1. First, you will definitely need a portable gas meter (to measure the oxygen level, Carbon dioxide (CO2), Lowest Explosive Limit - Combustible gas (LEL - <10%) & Hydrogen Sulphide (H2S).
  2. A adequate portable ventilation fan to provide ventilation to your confined space, with proper ducting.
  3. Ensure that the workers enter the confined space with minimum of a buddy system. (The one will the portable meter shall enter the confined space & his buddy shall await at the entrance.
So, what is the proper procedures on entering a confined space?
  1. Quite identical to all works, apply for a permit to enter a confined space from your safety officer / confined space assessor.
  2. Before entering a confined space, ensure that the opening for the confined space are opened. Identify the types of cargo that are stored inside the confined space to evaluate on the potential hazards (e.g: types of hazardous gas).
  3. Conduct an initial gas check with a gas meter to check on the oxygen level, carbon dioxide level & any present of hydrogen sulphide & combustible gas.
  4. Shall any of the four parameters failed to meet the safe condition, connect the portable ventilation fan with ducting into the confined space & ventilate the area to a reasonable time. Preferable to conduct gas checks at every 30 mins interval.
  5. Shall the gas meter identify that the confined space is well ventilated, enter the confined space in this order. First to go in, last to come out. The first person shall be the one who carried the portable gas meter. He/she shall wear the portable gas meter at least above 1m from his feet. He/she shall evacuate the group when he observed any danger indicate from the gas meter. He/she shall also be the last person to exit from the confined space.
  6. Shall the confined space be previously contain any flammable or toxic substance, the confined space shall be scheduled for a every 3hr gas check. Other situation will be at an interval of 6hr. The records of the air level shall be recorded & display at the entrance of the confined space at all times together with the permit.
  7. Once all work had been done, conduct a last check in the confined space, ensure that no tools & foreign materials are left in the area. Upon ensuring that the area is vacant, exit from the confined space & locked up the area. Inform your safety officer / confined space assessor to close the permit.

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