Analyzing the Workplace
Initial Assessment
Now that you have reviewed the structure, scope and application of the HCS and employer responsibilities, it's time to get down to business.
The first task is to determine what chemicals you have in your workplace. It's important for the person conducting the initial assessment to be familiar with the definitions and characteristics of hazardous substances and chemicals.
Hazardous Substances and Chemicals
Hazardous Substances: The HCS defines substances as chemical elements and their compounds in the natural state or obtained by any production process. This includes any additive necessary to preserve the stability of the product and any impurities deriving from the process used. However substances do not include any solvent which may be separated without affecting the stability of the substance or changing its composition.
Hazardous Chemicals: The HCS defines hazardous chemicals as those that are classified as physical hazards or health hazards, simple asphyxiants, combustible dusts, pyrophoric gases, or hazards not otherwise classified.
Physical Hazards: The HCS defines physical hazards as chemicals that pose a danger because of how they behave physically—for example, whether they can catch fire, explode, or react with other substances. The effects for determining whether a chemical is classified as a physical hazard are summarized below.
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Explosive: A chemical that can rapidly produce gas and pressure, causing damage or blast effects.
Example: A deteriorated old blasting cap or explosive primer accidentally jostled during cleanup could detonate, sending fragments and shock waves through the work area. -
Desensitized Explosive: An explosive chemical mixed with water or another substance to reduce its explosive properties.
Example: A shipment of ammonium nitrate prills (bead-like pellets) contaminated with water may not explode easily, but if dried during handling at a spill site, it could regain explosive potential. -
Flammable: Gases, liquids, or solids that catch fire easily at normal temperatures.
Example: A flammable liquid like gasoline or solvent on an oily rag left near a spark from a generator could ignite, creating a fire hazard. -
Oxidizer: Chemicals that supply oxygen and make fires burn hotter or start more easily.
Example: Liquid oxygen or solid oxidizers used in welding operations near oily surfaces can accelerate a fire if they contact fuel sources. -
Self-reactive: Chemicals that can decompose rapidly without oxygen, releasing heat and pressure.
Example: Certain peroxy compounds used in specialty cleaners may break down if left in the sun, releasing heat and potentially triggering a reaction. -
Pyrophoric (liquid or solid): Materials that ignite spontaneously when exposed to air.
Example: Finely divided iron sulfide formed in sludge tanks can ignite upon exposure to oxygen during cleaning, causing unexpected fires. -
Self-heating: A material that can heat itself up when exposed to air, eventually reaching ignition without a flame.
Example: Large piles of oily rags or waste sawdust on a cleanup site can slowly heat up and eventually catch fire without an external flame source. -
Organic peroxide: Chemicals with an unstable -O-O- bond that can break down violently.
Example: Some peroxide-based cleaners or polymerization initiators stored improperly on site could decompose and release heat, risking fire or explosion. -
Corrosive to metal: Chemicals that eat away at metal surfaces.
Example: Acidic spill cleanup agents splashed on metal storage tanks or steel tools can corrode the surface, weakening structural integrity. -
Aerosol: Pressurized containers that release particles or liquids under pressure.
Example: Aerosol cans of lubricant or rust inhibitor left in a hot truck bed can rupture, ejecting contents and fragments. -
Gases under pressure: Gases stored at high pressure that may explode if the container fails.
Example: A compressed gas cylinder (e.g., nitrogen or oxygen) stored incorrectly near hot equipment can rupture and launch like a rocket. -
Chemicals under pressure: Liquids or solids pressurized with gas that can release energy if the container fails.
Example: A pressurized cleaning solution cylinder used for high‑pressure washing that is damaged during transport can leak violently. -
Flammable gas emitted when in contact with water: Chemicals that react with water to produce flammable gases.
Example: Sodium metal or other alkali metals reacting with water at a shoreline cleanup could produce hydrogen gas, which is highly flammable.
For additional information, see Appendix B to 1910.1200 - Physical Hazard Criteria.
Health hazards: The HCS defines health hazards as chemicals which are classified as posing one of the following hazardous health effects:
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Acute Toxicity (any route of exposure):
Harmful or fatal effects that occur after a single or short-term exposure by breathing, skin contact, or swallowing.
Example: Breathing in high levels of hydrogen sulfide (H₂S) can lead to unconsciousness or death within minutes. -
Skin Corrosion/Irritation:
Skin corrosion causes permanent skin damage, while skin irritation causes temporary redness or inflammation.
Example: Hydrofluoric acid can cause severe, deep burns upon skin contact. -
Serious Eye Damage/Eye Irritation:
Serious eye damage causes permanent eye injury, while eye irritation causes temporary eye effects.
Example: Ammonia vapors can cause eye irritation and, in high concentrations, permanent eye damage. -
Respiratory or Skin Sensitization:
Causes allergic reactions in the lungs or on the skin after repeated exposure.
Example: Isocyanates used in industrial coatings can cause asthma-like symptoms or severe rashes. -
Germ Cell Mutagenicity:
Causes genetic changes that may be passed on to future generations.
Example: Some laboratory solvents or industrial byproducts are considered mutagens. -
Carcinogenicity:
May cause cancer or increase the risk of developing cancer after exposure.
Example: Benzene is a known carcinogen and has been linked to leukemia in oil and gas workers. -
Reproductive Toxicity:
May harm fertility, reproductive organs, or the development of an unborn child.
Example: Lead exposure can reduce sperm count and cause developmental problems in unborn children. -
Specific Target Organ Toxicity – Single Exposure:
Causes damage to a specific organ after one exposure.
Example: A single exposure to carbon monoxide (CO) can result in severe headache, dizziness, and confusion. -
Specific Target Organ Toxicity – Repeated or Prolonged Exposure:
Causes damage to specific organs after repeated or long-term exposure.
Example: Repeated exposure to solvents like toluene can damage the nervous system. -
Aspiration Hazard:
Can cause serious lung injury if swallowed and enters the lungs.
Example: Ingesting or vomiting up mineral spirits or gasoline can cause aspiration into the lungs.
For additional information, see Appendix A to 1910.1200 - Health Hazard Criteria.
Knowledge Check Choose the best answer for the question.
2-1. What does the HCS classify as a physical or health hazard, a simple asphyxiant, combustible dust, pyrophoric dust, or a hazard not otherwise classified?
You forgot to answer the question!