Fire’s visible destruction is obvious, but the invisible aftermath can quietly cripple your most valuable assets…

When a fire breaks out, the visible destruction often takes center stage—but what about the hidden, long-term damage caused by smoke? Even if the flames didn’t directly melt or burn your equipment, the smoke and its by-products can cause extensive, lasting harm to sensitive components.
This article explains how smoke from a fire, especially one involving plastics and synthetics, can silently degrade your machinery.


The Corrosive Nature of Smoke

Smoke isn’t just soot; it’s a complex mix of solid particles, gases, and aerosols. When materials like plastics, wire insulation, and other synthetic polymers burn, they release highly corrosive gases, most notably hydrogen chloride (HCl) – (see further notes). When this gas mixes with moisture in the air, it forms hydrochloric acid– (see further notes). This acidic residue settles on every surface, silently beginning a process of corrosion that can compromise the integrity of your machinery over time.


The Impact on Electrical Systems

Wiring and electronics are particularly vulnerable to smoke damage. The hydrochloric acid from the smoke attacks the copper conductors, causing a type of corrosion known as pitting. This leads to a loss of conductivity and can cause intermittent electrical shorts, degraded signals, or complete circuit failure. The smoke residue can also act as a conductive path between wires, leading to unexpected electrical issues. Even after a fire is extinguished, the acidic residue continues to eat away at the electrical components, leading to potential failures months or even years later.


Effects on Metals and Structural Components

While steel and aluminum won’t melt from indirect smoke exposure, they can still be significantly damaged. The acidic residue from the smoke can degrade protective coatings and paint, leaving the bare metal exposed to rust and further corrosion. Over time, this can weaken welds and joints, compromising the structural integrity of the machine’s frame and other critical components.


What to Do After a Fire

Cleaning up smoke damage requires more than just wiping down surfaces. A professional cleanup is essential to ensure all corrosive residue is neutralised and removed.

  1. Safety First: Do not operate the machine. Electrical systems may be compromised, creating a significant hazard.
  2. Professional Assessment: Have a professional inspector evaluate the full extent of the damage. They can identify hidden corrosion and compromised components that are not visible to the naked eye.
  3. Specialised Cleaning: Use specialised cleaning solutions to neutralise the acidic residue. Standard cleaning agents can spread the contaminants and worsen the problem.
  4. Component Replacement: Replace any components that have been directly exposed to smoke, especially electrical parts and sensors. It is often more cost-effective to replace a part than to risk a catastrophic failure down the line.

Remember, a machine can look fine on the outside but be severely compromised from within. Taking the necessary steps to address smoke damage will protect your investment and prevent future equipment failures.

Need further service support or have some questions? Contact our Service Specialist Team HERE

Want to learn more about Fire & Smoke Restoration? Learn more by completing the IICRC FSRT Course, IICRC HST Course, or Ascend Foundation Hazardous Environmental Cleaning Course offered by Cleaning Systems Ascend Training (“NZ Institute of Cleaning Science”) – NZ’s ONLY IICRC Approved School.

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Further Notes:

Hydrogen Chloride: Hydrogen chloride (HCl) is a colorless, pungent-smelling gas with industrial and technological uses, such as metal pickling and chemical manufacturing. It is highly soluble in water, rapidly forming hydrochloric acid, which is corrosive and can cause serious burns. The gas is irritating to the respiratory tract and eyes, and it is heavier than air, posing a risk of oxygen deficiency in enclosed spaces.  

Key Properties

  • Chemical Formula: HCl
  • Appearance: Colourless gas with a strong, pungent odour.
  • Solubility: Very soluble in water to form the strong acid, hydrochloric acid.
  • Corrosivity: Highly corrosive and irritating to skin, eyes, and mucous membranes, especially when moist.
  • Density: Heavier than air and can accumulate in low-lying areas, leading to an oxygen deficit.

Industrial & Technological Uses: Hydrogen chloride and hydrochloric acid are used in various industries, including:

  • Metal Processing: For cleaning, electroplating, and pickling steel.
  • Chemical Manufacturing: To produce vinyl chloride, dyes, fertilizers, and other organic and inorganic compounds.
  • Other Industries: In the photographic, textile, and rubber industries, as well as for refining soap and processing minerals.
  • pH Control: Hydrochloric acid is used in swimming pools and water treatment to adjust pH.

Hydrochloric Acid: A highly corrosive, strong mineral acid that is an aqueous solution of hydrogen chloride gas. It is also known by its older names, muriatic acid and spirits of salt.

  • Chemical Formula: HCl
  • Appearance: Colourless to slightly yellow, transparent liquid with a distinctive, pungent, and irritating odour. Concentrated solutions produce acidic fumes.
  • Corrosivity: Highly corrosive and can attack and dissolve many metals, except for certain noble metals like gold and platinum. The reaction with most metals produces flammable and explosive hydrogen gas.

Industrial & Technological Uses: Hydrogen chloride and hydrochloric acid are used in various industries, including:

  • Metal Processing: For cleaning, electroplating, and pickling steel.
  • Chemical Manufacturing: To produce vinyl chloride, dyes, fertilizers, and other organic and inorganic compounds.
  • Other Industries: Oil & Gas production, Water treatment plants (regulates pH of solutions), Diluted in household cleaners – “Muriatic Acid”, Metallurgy – ore refineries
  • pH Control: Hydrochloric acid is used in swimming pools and water treatment to adjust pH.