What is considered entry into a confined space? Working in confined spaces entails a problem of additional risks that force us to be more demanding in the precautions that workers must bear in mind. Works in confined spaces represent multiple risks due to the accumulation of toxic or flammable substances and the shortage of oxygen likewise.
The origin of accidents that occur in work in confined spaces is due to the lack of training and the lack of communication.
DEFINITION:
An enclosure or confined space is “any totally or partially enclosed space, with limited entry and exit openings, in which toxic or flammable contaminants may accumulate, or have an atmosphere deficient in oxygen and that is not designed for a continued occupation for the worker”
TYPES OF CONFINED SPACES
Tank, Vessels, Silos, Vaults, Pit, Manhole, Tunnels, Pipeline, Excavation more than 1.2 meters, etc.
RISKS IN CONFINED SPACES
- Oxygen deficiency
- Presence of flammable gas
- Presence of toxic gas
GENERAL RISKS
The general risks of confined spaces are the danger of interior atmosphere, are due to contamination. Among the general risks of confined spaces, the following stand out:
- Entanglement.
- Engulfment
- Electrocution.
- Falls
- Postural risks.
- Communication problems.
- Physical environment:
- Cold and heat.
- Noise.
- Vibrations
- Illumination.
What is required for confined space entry?
AUTHORIZATION OF ENTRY TO THE PREMISES
This authorization is the basis of any plan to enter an enclosure or confined space. The objective of this authorization is to guarantee that those responsible for production and maintenance have adopted a series of fundamental measures so that they can intervene on the premises.
It is recommended that the established entry authorization system includes, as a permit-to-work system checklist, the review and control of a series of key points (cleaning, purging, decompression, etc.) likewise.
MEASUREMENT AND EVALUATION OF THE INTERIOR ATMOSPHERE
The control of the specific risks due to dangerous atmospheres requires environmental measurements with the use of suitable instruments. Carrying out a gas test before the work and continuously while the work is going on and it is susceptible to variations in the interior atmosphere.
OXYGEN MEASUREMENT
The percentage of oxygen should not be less than 20.8%.
ISOLATION OF CONFINED SPACE AGAINST VARIOUS RISKS
- The unexpected energy release and start-up of mechanical elements or the possible electrical tensioning.
- The contribution of polluting substances is due to losses or leaks in the conduits or pipes connected to the work area or due to a possible opening of valves.
VENTILATION
CONTINUED EXTERNAL SURVEILLANCE
Certainly, the person who will remain outside maintains continuously visual contact or by other effective means of communication with the worker occupying the interior space.
TRAINING FOR CONFINED SPACES
In an accident in confined spaces due to the lack of knowledge of the risk, it is essential to train workers so that they can identify what a confined space is and the severity of the existing risks.
Most importantly, training and instruction of workers for:
- Specific work procedures,
- Risks that they may encounter (asphyxiating, toxic, flammable or explosive atmospheres) and the necessary precautions.
- Use of atmospheric testing equipment.
- Procedures for rescue and evacuation of victims as well as first aid.
- Use of rescue and respiratory protection equipment.
- Communication systems between interior and exterior with detailed instructions on their use.
- Suitable types of firefighting equipment and how to use them.
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