When it comes to workplace health and safety, a “confined space” refers to an area that is enclosed with limited access. This type of area can be very dangerous, because it lacks ventilation and it can inhibit exit. For example, this might be the interior of a storage tank, a pipeline, a utility vault, a storage container, a mine, a silo or a manhole. A confined space could even include certain parts of a building, such as a room that is wrapped in plastic sheeting for painting and does not allow vapour to be emitted.

These spaces are large enough for a person to enter, but they are not designed to be continuously occupied. Also, these spaces can have the potential for a serious hazard to be present.

Confined spaces can be hazardous when unbreathable gases are present, or when there is a risk of submersion in liquids or free-flowing granular solids (such as in a grain bin). Many of the accidents that occur when working in confined spaces are due to when untrained workers attempt to rescue a co-worker and unfortunately succumb to the same fate as them. There also might be a risk of a fire within the space, an explosion or excessive heat.

Workers in confined spaces are also at risk of asphyxiation from toxic gas, as well as at risk from flooding, fires, falls and getting trapped within the space. Sometimes these risks are so severe that working within the confined space requires a permit.

Workplace health and safety training covers working in confined spaces and outlines the skills required for entering these spaces safely. It is important that all workers who will be working within confined spaces follow the appropriate health and safety procedures, so that they can reduce their risk of death or injury.

Reducing Risk When Working in a Tight Spot

When you are working within confined spaces, there are a number of ways that you can reduce the risk. Here are a few important pointers to keep in mind:

  • Workers should have the appropriate health and safety training relevant to their position, which will help them to identify risks and establish good working procedures. A safe plan of action should be known by all workers so that they are aware of how to enter and exit the space.
  • A full risk assessment and survey of the working area should be conducted before work proceeds and any physical hazards should be dealt with prior to entry.
  • While the work is being carried out, the space should be monitored and tested for oxygen content, toxicity, flammability, explosive hazards and any other possible risks.
  • Workers who are conducting work in confined spaces should be using all of the appropriate safety equipment, such as fall protection equipment and protective breathing gear. Also, all air monitoring, ventilation, lighting and communication equipment should be appropriate and approved for use in confined spaces.
  • When working in a confined space, it is important to always maintain constant contact with a trained attendant, either visually or via a two way radio. This is important, as it allows supervisors to send in a rescue team as soon as any danger begins to occur.
  • All confined spaces should be clearly signposted and exit and entry openings should be clearly marked.
  • The air within confined spaces needs to be tested regularly for contaminants and oxygen, using the proper equipment.

Monitoring the Atmosphere

Monitoring the atmosphere of the confined space is the most important thing to keep in mind when it comes to workplace safety. Most of the deaths that occur within confined spaces are due to contaminants and toxins in the atmosphere. Often, the workers within the confined spaces are not able to sense these poisonous gases because they are colourless and odourless. Also, the sense of smell will diminish after a short exposure, making workers think that the gas has gone away – when they have only become immune to the smell. This is why the only accurate way to monitor and detect toxic gases in the atmosphere is to use instruments.

Whenever you are working within a confined space, you should have the appropriate equipment in place to measure the oxygen concentration of the space. According to the health and safety regulations, the concentration of oxygen should be between 19.5 and 23.5 percent. Any flammable gases or vapours should only be present at below 10%. However, the ideal working situation involves no flammable gases or vapours.

It is important to determine what gases you are looking for before you set up a system for monitoring the air. If there is a gas present, but you don’t have the sensors in place for it, it could cause a hazard that you are not even aware of. Once you are aware of the dangers that are present, you will be able to decide on the right course of action for making the space safe – such as ventilation, breathing equipment, etc.

Rescuing Someone From a Confined Space

Unfortunately, one of the major causes of death and injury from confined spaces is when other workers attempt to rescue their colleagues. Rescuing someone from a confined space can be very dangerous and a rescue should not be attempted without a plan and the correct safety equipment.

Rescuers should be wearing a self-contained breathing apparatus, otherwise they are at risk of breathing in the same toxic gases that affected the person they are rescuing.

Emergency rescue procedures need to be practiced regularly and you should ensure that all exits and entrances are large enough to permit the rescue team and all of their equipment to enter. When you take health and safety training, you will learn more information about the proper way to rescue someone from a confined space.

Working within a confined space can be dangerous, so be careful and diligent with your health and safety procedures in order to prevent unnecessary death and injury.