What are Class 8 Corrosive Materials?

Learn about and understand the regulatory complexities surrounding Class 8 corrosive materials. Q&As include:

1. What are Class 8 corrosive materials?
2. What are acids and bases?
3. How do acids differ from bases?
4.  What is oxidizing potential?
5. What are some examples of Class 8 corrosives?
6. How do you store Class 8 corrosives?
7. What agencies regulate Class 8 corrosives?
8.  How do you transport Class 8 corrosives?
9. What are the penalties for non-compliance with Class 8 disposal regulations?
10.  Where can you get local help managing Class 8 corrosive materials?

What are Class 8 corrosive materials?

Class 8 corrosives are defined under the Transportation of Dangerous Goods Regulations (TDG) are acids or bases that can cause severe damage to living tissue or severely corrode metals through chemical action. More specifically:

• They can cause visible destruction or irreversible alterations to human skin tissue at the site of contact.
• They have a severe corrosion rate on steel or aluminium surfaces, exceeding 6.25 mm per year at a test temperature of 55°C.

What are acids and bases?

Liquids and solids that are deemed Class 8 corrosives are either acids or bases. Something is considered an acid or a base dependent on its pH level, where “pH” stands for “potential hydrogen.” (Some people say it’s “power hydrogen.” Those with a flair for Latin prefer pondus hydrogenii, which, if you believe everything Google tells you, translates to “weight hydrogen.”)  Anyway…

How do acids differ from bases?

In effect, they don’t. They’re both as corrosive as heck. But acids give up hydrogen protons while bases receive them. And the movement of hydrogen in such a manner—in one direction or the other—is highly corrosive. I.e., it burns.

The reference point for calling something an acid vs. a base is pure water, which has a pH = 7, meaning that the “H” protons in your H2O don’t migrate in one direction or the other to cause corrosive mischief. A substance with a pH level less than 7 is called an acid. Higher, and then it’s called a base.

(N.B. While acids are predictably called “acidic,” bases are less intuitively known as “alkaline.”)

As you might guess, the more acidic or alkaline a substance, the more corrosive it will be. But less obviously, the numbers aren’t linear. (You might say this is “exponentially” important to understand.)

Consider:

• Remembering that a lower number means relatively more acidity, a pH = 4 is ten times more acidic than pH = 5, and 100 times more acidic than pH = 6.
• Similarly, remembering that a higher number is relatively more alkaline, a pH = 13 is ten times more alkaline than pH = 12, and 100 times more alkaline than pH = 11.

What is oxidizing potential?

We knew you were going to ask that.

Next time you do a Big 8, you might ponder that most commercial lemonades and sodas have a pH of about 2.5, not too far (thinking linearly for a moment) from hydrochloric acid (pH = 1.1 @ .380 concentration).

To understand why imbibing one is okay while the other is definitely contraindicated as a mixer, consider that in addition to pH, acids also have something called “oxidizing potential.” This is their relative ability to strip electrons. The ingredients in soft drinks—while very acidic—nonetheless have little oxidizing potential. So, drink up.

(We might mention here that at 4.0, beer is significantly less acidic than soda. Draw your own conclusions.)

What are some examples of Class 8 corrosives?

There are many kinds of Class 8 corrosives. Herein we list three common acids and three common bases, each in typical consumer/industrial concentrations:

Acids

• Hydrochloric acid (HCL) (pH = 1.1 @ .380 concentration) is used in water and salt purification, as well as making batteries, fireworks, leather, and building materials. Your digestive system also produces HCL, sometimes to spectacular effect. See heartburn.
• Sulfuric acid (H2SO4) (pH = 0.5 @ .335 concentration) is used to produce dyes, paints, pigments, explosives, and most famously: fertilizers and lead-acid batteries. This stuff is truly wicked, uncontrollably boiling and bubbling when it accidentally comes into contact with plain old water.
• Nitric acid (HNO3) (pH = 1.2 @ .680 concentration) has many of the same uses as H2SO4. It’s also used to remove warts, although we counsel extreme caution when doing so, since it can also dissolve most metals. And mixed with HCL, it forms a fuming liquid used to dissolve gold and platinum—should the need arise.

Bases

• Ammonium hydroxide (NH4OH) (pH = 10.52 @ 1mM concentration) is used as a refrigerant, as well as for manufacturing detergents, textiles, soaps, ceramics, pharmaceuticals, inks, and explosives. It’s also used to clean glass—and added to food to control acidity.
• Potassium hydroxide (KOH) (pH = 10.98 @ 1mM concentration) shows up in the production of fertilizers, biodiesels, and soft soaps. It’s also used as an electrolyte (in electrochemistry, of course), and in a process commonly called “chemical cremation” (which we don’t even want to think about).
• Sodium hypochlorite (NaClO) (pH = 11 @ .05 concentration) is used in waste management, food production, and as a bleach or disinfectant. It’s also a pesticide.

How do you store Class 8 corrosives?

Very carefully. Violent reactions between incompatible acids and bases can cause fires and explosions, as well as produce toxic and/or corrosive gases.

Storing Class 8 corrosives require specialized cabinetry that—depending on your location—might include such features as self-closing doors that are close-fit, cannot swing inward, are “escapable” from the inside, and secured by at least two catches.

Other requirements might be the cabinet’s construction of corrosive-resistant material or at least being protected by a corrosion‑resistant lining or coating. Shelves should be perforated to accommodate airflow.

The cabinet’s base should form a liquid-tight sump—and probably be large enough to hold a specified percentage of its total capacity, should the worst happen. Oh…and blue. By convention—although not by law—cabinets designed for Class-8 corrosives are blue.

Obviously then, that second-hand IKEA wardrobe you found on Kijiji isn’t going to cut muster. You should get expert advice.

What agencies regulate Class 8 corrosives?

The answer to this depends on whether you’re dealing with transportation, workplace use, consumer products, environmental release, or some other application of Class 8 corrosives.

Each federal, provincial, and/or municipal agency has its own set of regulations, classification systems, and compliance requirements that might apply to your particular situation. The way they interact can be a major impediment to doing business—unless you get expert advice.

All that said, Class 8 corrosives are regulated by several agencies depending on the context.

TDG is the primary federal agency responsible for the transportation of dangerous goods. It regulates the classification, packaging, marking, labelling, placarding, shipping documentation, and training requirements for handling Class 8 corrosives.

Health Canada regulates corrosive substances under various acts including:

• The Hazardous Products Act and Hazardous Products Regulations
• The Consumer Chemicals and Containers Regulations
• The Workplace Hazardous Materials Information System

Environment and Climate Change Canada (ECCC) oversees environmental aspects through:

• The Canadian Environmental Protection Act (CEPA)
• Various environmental regulations that might apply to corrosive substances
• Canadian Food Inspection Agency (CFIA) might be involved if corrosive materials are used in food processing or agricultural applications.

Also be mindful that provincial and territorial governments also have jurisdiction over workplace safety and may regulate corrosives in occupational settings through their respective occupational health and safety agencies.

How do you transport Class 8 corrosives?

You just can’t throw a Class 8 corrosive into the back of your F-150 and haul it down to the dump. The dump won’t take it, and your F-150 might dissolve before you get there.

Instead, you need to hone how you classify the material by assigning it into one of three packing groups that are stratified according to the relative severity of the hazard it poses. These are:

• Packing Group I (high danger—most corrosive) causes full thickness destruction of intact skin tissue within 60 minutes of 3-minute exposure or less.
• Packing Group II (medium danger) causes full thickness destruction of intact skin tissue within 14 days after 3-to 60 minutes exposure.
• Packing Group III (low danger, least corrosive, but still significant) causes full thickness destruction of intact skin tissue within 14 days after 1-t0-4 hours exposure.

Other shipping requirements include:

• Shipping manifest. This is a form-filling exercise completed by you. It indelibly attaches a hazardous waste to your enterprise as it migrates from your site to the hazardous waste management facility that will ultimately process it—along with all the legal, financial, and social liabilities that are endemic to hazardous material removal.
• Labelling. Labels are always diamond-shape; and their size must adhere to international standards, measuring at least 4″ x 4″ (100 mm) on each side, square-on-point. The Class 8 variety graphically features liquids spilling from two glass vessels, respectively doing damage to a hunk of metal, and someone’s hand.
• Segregation. When dangerous goods of different classifications are loaded into a vehicle, they might need to be segregated due to potential reactivity (see source).
• Personnel. Drivers must have TDG certification and workers handling the corrosives must be properly trained.
• Vehicles. Trucks must meet TDG standards for transporting hazmat and have proper ventilation and containment systems.

What are the penalties for non-compliance with Class 8 disposal regulations?

Non-compliance with regulations for Class 8 disposal in Canada can result in severe penalties, including substantial fines, cleanup orders, and potential criminal charges for serious violations.

Provincial environmental authorities have broad enforcement powers and can issue stop-work orders, require remediation of contaminated sites, and pursue cost recovery for environmental damage.

Recent enforcement actions have seen fines ranging from thousands to millions of dollars, depending on the severity and duration of violations. Companies might also face civil liability for environmental damage and third-party claims related to improper solvent management.

Where can you get local help managing Class 8 corrosive materials?

Anything harbouring the ghoulish potential to cause severe damage to living tissue requires safe and legal hazardous waste management.

Don’t take chances.

Secure properly licensed and experienced hazardous waste management experts to ensure that all consumer and commercial corrosives are properly stored, segregated, transported, and ultimately disposed of in compliance within & across all federal, provincial, and municipal mandates.

The legal, financial, and reputational liabilities of not doing so are formidable.

Contact us today.