Work in Confined Spaces
4. Preparing the Job
4.1. Feasibility
Before commencing work in a confined space or setting, the Works Supervisor and/or Foreman is to determine its feasibility. To do so, they are to visit the area previously, if possible, accompanied by the client.
This feasibility study is to take the form of the corresponding Health and Safety Plan, which is to include details on the following, among other questions:
- Means of access to the enclosure: ladders, etc.
- Necessary work equipment: appropriate protected electrical equipment and lighting system, communication systems such as broadcasting or transmitting devices, etc.
- Necessary measuring equipment: equipment for testing the air, for measuring gases, for measuring gases and fumes.
- Hazards and preventive measures: continuous control of the atmosphere inside, characteristics of the ventilation to install, etc.
- Necessary Personal Protection Equipment: autonomous or semi-autonomous breathing equipment, harnesses and safety rope, tripods, articulated arms, etc.
- Fire-extinguishing equipment.
4.2. Measurement, assessment and control of the atmosphere inside
- If the confined space has contained hazardous substances, these must be completely removed using a forced air renewal system to ventilate the space.
- The oxygen concentration is to be measured, the percentage in the atmosphere inside must not be lower than 19.5%.
- Toxic or inflammable gases are also to be measured, depending on the type and conditions of the enclosure by means of specific detectors.
- If there is less than 19.5% of oxygen or toxic gases at concentrations above their exposure limits, autonomous or semi-autonomous breathing equipment is to be used, if applicable, as well as suitable ventilation.
- If there exists the possibility of inflammable atmospheres the non existence of sources of ignition is to be scrupulously monitored in the vicinity of the mouth of the enclosure.
MEASURING EQUIPMENT - ATEX LIGHTING – EXTRACTOR AND/OR AIR SUPPLY DEVICES
4.3. Authorisation to enter and work in a confined space
- This authorisationaims to guarantee that all those with responsibilities have taken the basic measures to be able to intervene in the enclosure without risking the health or safety of workers and that the workers who carry out the work are perfectly qualified to do so.
Personnel: Work must be carried out by at least two workers. Both must be apt for this type of work in accordance with the results of the last medical examination corresponding to health surveillance. - At least one of them (the one who monitors the work from outside) is to have received first-aid training and have a basic level of 50 hours training in ORP, as he is to be named the Preventive Resource figure on the job.
