Archive for the ‘ Confined Spaces ’ Category

Confined Space Hazards Video – Xcel Energy Case

The US Chemical Safety Board has recently released confined space hazards video, related with work accident in a tunnel at Xcel Energy Company’s hydroelectric power plant in Georgetown, Colorado, US. It was happened on October 2, 2007.

In that work accident, five people were died and three others injured. When it happened, a fire erupted 1,000 feet underground in that tunnel.

CSB explained how the fire accident happened through the confined space hazards video. Watch this video and take important notes afterward. You will see that confined space is one of the most dangerous workplaces. (more…)

Accidents in Confined Spaces: Oxygen Deficiency

In this video, we will see an accident in confined space at Valero Refinery, Delaware, USA, in November 2005. This accident caused two workers died.

Nitrogen purging is a procedure required when equipment containing flammable material will be opened. It means that after nitrogen purging or nitrogen substitution oxygen concentration inside the equipment will be very low, as well as area around the confined space opening. And that made this accident happened. (more…)

Confined Space Pre-Entry Check List

confined-space-entry-checklistA series of questions in confined space pre-entry checklist shall be completely answered prior to entering any confined space. The confined space checklist will ensure entrants, attendants, supervisors and rescue team members in safe condition. Do not enter the confined space until it is surely safe.

Answer the questions below by “YES” or “NO”. Then, follow up immediately question with answer “NO”.

1. Safety Meeting

  • The works that are planned to be performed inside confined space are clearly described, including the work schedule.
  • Contents of the confined space are clearly identified.
  • Preparation works have been completed, including removal and clean up of chemicals from the confined space.
  • Hazard identification and risk assessment have been finished.
  • All aspects of safety measures have been discussed and identified.
  • Name of entrants, attendants, supervisors and rescue team have been determined.

2. Permit

  • Confined space entry permit has been issued.
  • The confined space permit is up to date.
  • If hot work will be carried out, get hot work permit too.

3. Verification

  • All instruments used in atmospheric testing are calibrated.
  • The person in charge for atmospheric testing is qualified and competent
  • The atmospheric in confined space has been tested.

4. Testing

  • Oxygen content is at least 20.8%, but not more than 21%.
  • Are the following toxic, flammable or vapor gases present? Hydrogen sulphide, carbon monoxide, methane, carbon dioxide, others (please mention)
  • Checking and evaluation of the gas measurement results have been done.

5. Monitoring

  • Make sure the atmospheric in confined space will be monitored while work is going on.
  • Prepare a monitoring time table and items for the atmospheric in confined space.

6. Ventilation

  • The confined space has been ventilated before entry.
  • Ventilation will be continued during entry.
  • Make sure that the air intake (supply) for the ventilation system is free of combustible dust/vapor and toxic gas/vapor.
  • If the atmospheric is unacceptable, it shall be ventilated and re-tested.

7. Isolation

  • The confined space has been isolated from other systems.
  • Electrical equipment has been locked out.
  • Block valves have been closed and blind plates have been inserted.
  • Mechanical equipment has been blocked, chocked and disengaged.
  • The confined space has been separated from pressurized pipe lines and equipments, by disconnecting or closing the valves.
  • Tags have been put at the related block valves and blind plates to the confined space.

8. Equipment, Clothing, Tools and Personal Protective Equipment

  • Special equipment has been provided.
  • Special clothing required for the work inside confined space have provided (chemical suit, boots, safety shoes, goggles)
  • Special tools required have been provided.
  • Required personal protective equipments have been provided and ready to be used.
  • Lighting requirement has been fulfilled.

9. Training

  • The entrants, attendants, supervisors and rescue teams have followed confined space entry training.

10. Standby/Rescue Team

  • There is a standby person or rescue member on the outside of confined space in constant visual and auditory communication with the entrants inside the confined space.
  • Make sure that the standby person is able to see or hear the person inside confined space at all times.

Double check the above confined space checklist to ensure there are no left items. Afterward, we can proceed to the next step prior to entry the confined space.

Source: IACS Rec.2000/Rev.2 2007

Confined Space Fatalities Video

Confined space hazards could present hazardous conditions that can lead to fatalities. The following confined space safety video shows accidents in confined spaces. See how confined space fatalities could happen.


12 Confined Spaces Hazards

confined-spaces1Confined space is one of the most deadly spaces in the workplaces. It is because of confined spaces contain many potential hazards and have restricted exits way.

Related to confined spaces, OSHA requires that:
a. All confined spaces in the workplaces shall be identified.
b. Confined spaces shall be treated as hazardous until proven.
c. All confined space hazards shall be identified.
d. Appropriate response should be given to these hazards before entry.

Confined space hazards can be classified into hazardous atmosphere, physical hazard, chemical contact hazard and biological hazard. The hazard list below is hazards that are commonly identified in a confined space.

  1. Oxygen rich (greater than 23.5%). This condition will introduce fire or explosion, especially when flammable vapor exists. So never use pure oxygen for ventilating a confined space. Use normal air supply only.
  2. Oxygen deficient (less than 19.5%). Oxygen deficient or lack of oxygen can cause unconsciousness to death. Oxygen concentration in a confined space can be declined due to nitrogen intrusion, welding, grinding, oxidation, sandblasting or coating.
  3. Oxygen and the existence of flammable vapors or gases can create flammable atmosphere. Chemical reaction and concentration of combustible dust may also create flammable atmosphere.
  4. Toxic atmosphere. It is introduced when a toxic chemical or gas is stored in a tank/holder, when carbon monoxide or hydrogen sulphide is produced through decomposition or work being done in the confined space.
  5. Corrosive atmosphere. Hydrochloric acid and ammonia are examples of chemicals that can build up a corrosive atmosphere.
  6. Physical configuration hazards. The use of ladder and scaffolding, wet surface, uneven bottom, bends in tunnels, narrow area or poor lighting can cause physical hazards to the workers inside confined spaces.
  7. Mechanical hazards. Mixing vessel, which is equipped with blades, can introduce mechanical hazard when workers come into the confined space (mixing vessel). Including in mechanical hazard is falling object.
  8. Surface hazard, for instance slips and falls.
  9. Noise hazards. Grinding work inside a confined space can result high level noise.
  10. Vibration hazards.
  11. Engulfment hazards. Engulfment hazard may happen when worker is entrapped by content of the confined space.
  12. Temperature hazards. Cold temperature and heat create temperature hazard inside a confined space.

Always bear in mind that hazards identification shall be finished before entering a confined space. Then, provide appropriate hazard controls to these potential hazards afterward.

Confined Spaces Definition

confined-spacesIn this post, we will talk about confined spaces definition. After reading this post, it is hoped that you could easily recognize confined spaces in the plant site and provide adequate hazard control against confined spaces hazards.

By definition, confined spaces mean spaces that are large enough spaces where workers can bodily enter and perform assigned works. Confined spaces, which can easily found in chemical plant site, at least have the following characteristics:

a. Have limited or restricted openings/ways for entry and exit.
b. Not designed and purposed for continuous workers occupancy.
c. Have poor natural ventilation.

According to the above definition, we should be able to identify all of the confined spaces exist in the plant site. And I believe we can easily identify them. Below are confined spaces that are commonly found in chemical plant site. Just add them through comment column if you would like to add another one and share with other readers

1. Solvent tanks
2. Pressure vessels
3. Boiler
4. Reaction towers
5. Product tanks
6. Gas holder
7. Absorber column
8. Kiln
9. Calciner
10. Resin exchanger column
11. Large piping line
12. Bulk chemical container

I have many experiences working in confined spaces during my assign work in chemical plant site. Storage tanks, pressure vessels and reactors are some of confined spaces that I had entered. Special precautions have to be fully given during work in confined spaces, otherwise accident will probably occur.

Subscribe To Updated News & Offers