Sensing Safety

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Suppose you are an operator at a tank farm. You intend to deliver concentrated hydrochloric acid from a road tanker to the appropriate storage tank. Figure 1 shows a schematic of the process.
filling Station Road Tankers
Figure 1. Schematic for filling storage tanks

The tanker contents flow to an adapter battery, from which they are admitted to the desired tank through a hose. At the battery, a single hose is reserved for conveying all of the fluids to their respective tank. You are aware that the facility contains a tank for storing sodium hypochlorite, which liberates chlorine gas upon combination with acids.

Three uses, ranked in order of decreasing importance:

  1. Sense of sight to check that the hose is fitted to the correct adapters at the tank and at the tanker truck prior to filling the tank.
  2. Sense of sight to detect visible chlorine emerging from the tank in the event of a gas release.
  3. sense of smell to detect chlorine gas in the event of release.

Fitting the hose to the correct adapter prevents the addition of hydrochloric acid to the hypochlorite tank—or vice versa—thereby preventing chlorine gas production. The next two detection methods are helpful for incident mitigation. You are unlikely to smell chlorine without considerable exposure to an emerging gas cloud, but can observe the cloud visually prior to exposure, allowing you to avert imminent danger.

You are a chemical engineer at a production facility, which houses a batch reactor and large quantities of flammable substances. Tankers deliver raw materials to the facility regularly. Provide three uses of the senses for hazard detection.
  1. Sense of sight for leaks, missing bolts, or states of disrepair in equipment
  2. Sense of sight for assessing whether possible ignition sources (such as vehicles) are located too close to flammable substances or process facilities
  3. Sense of sound for assessing the batch according to the sound of the agitator. Is the batch too dense? Has the reaction proceeded to an undesirable extent? Has the agitator failed?
In 2-3 sentences, comment on any shortcomings of the article.

This article does not account for people with disabilities that limit their ability to detect hazards with any of the five senses. The article does not emphasize enough the reliance of diagnostic equipment first and senses second. The diagnostic equipment can tell us of a failure or dangerous process condition far ahead of when it is detected via sound or smell. We should never be over-reliant on human senses for alerting us to dangerous or uncommon process conditions.