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Confined spaces and gas are not a good mix. In the blink of an eye, gas can fill up the space and make it impossible to breathe. There is no room for trial-and-error in this situation because death could come swiftly. That’s why gas monitoring is critical before entering these dangerous places – you need to know what you’re dealing with so that you can take steps to protect yourself from harm.
Deadly gases might be trapped inside, organic material might decompose and release toxic fumes, or chemical reactions like rusting might crowd out the oxygen workers need to breathe safely. It only takes seconds for the gas to kill someone in a confined space, so it’s important that everyone understands how gas behaves before entering one.
What is a toxic atmosphere?
Hazardous atmospheres are when there is not enough, or too much oxygen. Oxygen-deficient environments are when there is not enough oxygen. This can be very dangerous and can cause unconsciousness, brain damage, and death.
If you have a flammable/combustible/explosive atmosphere it means that you have gases or vapors that could catch on fire or explode if they come in contact with an ignition source like a grinding spark. Toxic atmospheres are when the air contains gases or vapors which may harm people if they breathe them in for long periods of time.
Which can be common sources of toxic gases?
Poisonous gases can come from a variety of sources like:
- Machine shops or factories with woodworking machinery which generate dust containing silica
- Any plant or factory that handles chemicals such as ammonia, ammonia nitrate fertilizer (e.g., anhydrous ammonia)
- Chlorine gas to purify drinking water and swimming pools
- Volatile Organic Compounds or VOCs for short
These are only a few examples. Let us explain VOCs more.
Volatile Organic Compounds
Volatile Organic Compounds, or VOCs for short, are compounds that evaporate quickly. They’re usually produced by certain industrial flaws (byproducts of manufacturing processes) and household chemicals such as adhesives, paints, plastic products, and others.
VOCs are gases that can produce harmful toxins when they react with other chemicals or form pollution. They’re commonly found in the air near busy roads, as well as near factories, outdoor grills, and solvents such as paints. They’re also found in waterborne sources such as streams and rivers.
The number one danger of toxic atmospheres is that low-level exposures are chronic — even at low levels of exposure you’re going to be exposed constantly every day until the exposure stops (either naturally through the destruction of a pollutant substance or someone/something knocking it out).
VOCs are some of the toughest problems an indoor air quality specialist can deal with because their concentrations can go up to 1 million times what they were originally in just a day’s time. When you use perfumes or scented candles often in your home this number goes way up — VOC concentrations from these things can reach levels as high as 100 billion times their initial concentration!
VOCs are chemicals generated on industrial surfaces or emitted into the atmosphere from car exhaust. They react with oxygen to produce ground-level concentrations of pollutants, which negatively affect human health and the environment. For instance, benzene’s toxic effects at high levels include bone marrow damage and leukemia. Promoting VOC-free production methods by setting precautionary measures is important in order to maintain a healthy workplace environment.
Which are the most common gas hazards when you are in confined spaces?
Oxygen
Oxygen is a necessary element for humans to survive. In confined spaces, workers are always susceptible to the dangers of oxygen deficiency and excess. Oxygen can be harmful in two ways: lack or abundance because it controls our basic functions like breathing and heart rate while also causing dizziness, nausea, headaches, etc. if there’s too much of it in the air we breathe.
The Occupational Safety & Health Administration (OSHA) sets lower limits on how aerated an environment needs to be during work hours depending upon what types of activities people will do inside these areas as well as upper thresholds that should not ever exceed by more than 5%.
Hydrogen sulfide
Hydrogen sulfide, also known as sewer gas, is highly flammable. It’s often the product of decaying organic matter and can be colorless or visibly present due to combustion from exposure to air. The effects on a worker depending on how much they are exposed to over time; those operating in confined spaces should check their gas detector regularly for accuracy.
The effects vary depending only partially on how much an individual breathes in at one time; rather they depend more so upon their exposure length with higher amounts most likely causing death over time due to high levels being inhaled into the lungs faster than lesser concentrations would have been able to do so otherwise. In this case, workers are especially vulnerable within recessed spaces such as pits and storage tanks since hydrogen sulfide gas has the capability to form a gas pocket on long enough exposure.
Ammonia
Ammonia gas is also known as an ‘invisible killer’ because it’s colorless in its natural state and odorless, too! It can cause coughing up blood or severe lung damage which are dangerous symptoms that need prompt medical attention.
When this gas is in its pure form, it’s not too harmful but ammonia gas can be combined with other things like acids and chemicals that make for a deadly mix of gases: hydrogen sulfide gas or chlorine gas are two examples that have deadly effects when mixed with ammonia gas.
Carbon monoxide
If you’re lucky enough to be one of the rare individuals who can smell carbon monoxide, then I’m afraid your nose is about as useful in detecting it. The gas has no odor and an unsuspecting passerby might never know they are walking into a death trap until their lungs start burning…literally.
Carbon monoxide causes more than 50% of all fatal occupational gaseous poisonings because it’s colorless and odorless; meaning if there isn’t someone around with experience or equipment for protection – like those at Local Gas Company- things could go south very quickly without any warning signs whatsoever!
Keeping gas out of confined spaces
A confined space is a dangerous place to be. Given the plethora of harmful gases and vapors, it’s important that you monitor both toxic and flammable gases within these spaces on an ongoing basis for any sign of change in risk assessment conditions that may indicate potential danger or harm. Important stratospheric gases to check are Methane (CH4), Carbon Monoxide (CO), and Hydrogen Sulfide(H2S).
Working in a confined space is always risky, and the risk can be minimized by following guidelines such as abiding by the HSE-approved code of practice for safe working in confined spaces. One must avoid work activities that are carried out within these types of settings if it’s possible at all costs because there are hundreds of other tasks that need to take place regardless.
It should also be noted that monitoring oxygen levels with gas detection equipment before entering will ensure safety when carrying out any task while inside a closed-in area; this type of preparation ensures no one gets hurt or killed from an unexpected event.
The first step in maintaining a safe and healthy work environment is making sure the air quality within confined spaces stays at an acceptable level. However, before entering any area that might have poor Air Quality Standards- such as sewers or other enclosed areas with little ventilation – workers should take precautions to ensure they are not putting themselves into harm’s way by testing for hazardous gases from outside of those environments.
There are various ways that this can be done: lowering portable gas detectors like Crowcon T4s into the space; feeding tubes inside to draw samples using pumped gas detector instruments that detect single or multiple gasses depending on what your needs may be.
Conclusion
Dangerous gases and confined spaces are a dangerous mix. It can take only a few seconds for workers to succumb to a hazardous atmosphere, so there’s no room for learning as you go. Combinations of gasses such as chlorine gas with ammonia gas create an even bigger danger since they become fatal when mixed together in small doses; which means anyone who doesn’t know how much is too much could end up dying without warning signs beforehand. With hazardous atmospheres all around us, it’s important to know what a safe atmosphere is and how you can protect yourself.
