Hazardous chemicals and HazCom basics

Greenway's chemical room is a locked, ventilated room at the back of the warehouse. It holds the stock for the store: weed killers, insect sprays, fungicides, fertilizers, pool chemicals, lawn treatments, ice melt, lamp oil and cleaning products. The greenhouses have their own smaller cabinet of products used on the plants. And the yard has propane cylinders in a cage outside, plus fuel for the loader and the chipper.

Jordan was not allowed into the chemical room until he had done his HazCom training. Marisol ran it for him and two seasonal workers on a Thursday afternoon. She started by holding up two bottles that looked almost the same, one a lawn fertilizer and one a concentrated weed killer. 'Which one of these could put you in hospital if it splashed in your eye?' she asked. Nobody was sure. 'That's why we have labels,' she said, 'and that's why you're going to learn to read them.'

This lesson covers the basics of working safely with hazardous chemicals: how they can harm you, what the labels and pictograms mean, what a safety data sheet is, and what you must do to protect yourself. HSE-102 covers HazCom in much more depth.

How chemicals can harm you

Chemicals can cause two broad kinds of harm. Physical hazards come from what the chemical does: it may catch fire, explode, react with other chemicals, or be stored under pressure. Health hazards come from what the chemical does to your body: it may burn your skin or eyes, irritate your lungs, poison you, cause an allergic reaction, or cause long-term illness such as cancer or lung disease.

To harm you, a chemical has to get into or onto your body. There are four main routes:

• Breathing it in as a gas, vapor, mist, spray or dust. This is the most common route at work.
• Skin and eye contact, from splashes, spills, contaminated gloves or touching your face.
• Swallowing it, usually by accident, from eating, drinking or smoking with contaminated hands.
• Injection through the skin, from a puncture by a contaminated sharp object or a high-pressure sprayer.

Knowing the routes tells you how to protect yourself. Ventilation and respirators protect against breathing in. Gloves, goggles and clothing protect skin and eyes. Washing your hands before you eat, drink or smoke protects against swallowing. Handling sharp objects carefully protects against injection.

What HazCom is

HazCom, OSHA's Hazard Communication Standard at 29 CFR 1910.1200, is the United States system for giving workers information about hazardous chemicals. It is based on the Globally Harmonized System of Classification and Labeling of Chemicals, the GHS, which the United Nations developed so that chemicals are classified and labeled the same way around the world. OSHA aligned HazCom with the GHS in 2012 and updated it again in 2024.

HazCom has two sides. Chemical manufacturers and importers must classify their chemicals and provide labels and safety data sheets. Employers must keep the labels and safety data sheets, label containers in the workplace, keep a list of the hazardous chemicals on site, have a written hazard communication program, and train workers before they are exposed. ADOSH enforces HazCom in Arizona.

HazCom rests on the same main parts: labels, safety data sheets and training, held together by a written program. Each one backs up the others.

Labels

A shipped container label is put on a hazardous chemical by the manufacturer, importer or distributor. It must include:

• the product identifier, the name of the chemical;
• the name, address and phone number of the manufacturer, importer or other responsible party;
• pictograms, the symbols inside a red diamond border;
• a signal word, either 'danger' for more severe hazards or 'warning' for less severe ones;
• hazard statements that describe the hazard, such as 'Causes serious eye damage'; and
• precautionary statements that say how to prevent harm and what to do if exposed, such as 'Wear eye protection' and 'If in eyes: rinse cautiously with water for several minutes'.

When a product is poured into another container, such as a spray bottle, or when the original label falls off or becomes unreadable, the new container needs a workplace label. At Greenway, workplace labels are printed from the tablet and show the product name, how to handle it safely, and where to find the safety data sheet.

The unlabeled fungicide sprayer that Jordan found in Lesson 5 broke this rule. Nobody knew for sure what was in it. It was emptied into the hazardous waste drum, and the greenhouse now has a box of pre-printed workplace labels next to the mixing bench.

Pictograms

Pictograms give a quick visual sign of the type of hazard. HazCom requires eight GHS pictograms; a ninth, for hazards to the environment, may be used but is not required.

A few are easy to mix up. The flame means the product can burn. The flame over a circle means it is an oxidizer, which makes other things burn more fiercely; some pool chemicals are oxidizers. The exclamation mark means less serious health effects, such as skin irritation. The health hazard symbol, a person with a star-shaped burst on the chest, means serious or long-term effects, such as cancer, lung damage or harm to an unborn child. The corrosion symbol means the product can burn skin and damage eyes, or eat through metal.

A product can carry several pictograms. The weed killer concentrate Marisol held up carried the corrosion pictogram and the signal word 'danger', because it can cause serious eye damage. The lawn fertilizer carried only the exclamation mark and 'warning', for mild skin and eye irritation. They looked alike, but the labels told a very different story.

Safety data sheets

A safety data sheet, or SDS, is a document of several pages with detailed information about a product. Every hazardous chemical must have one from the supplier, and the employer must keep it where workers can get to it easily. At Greenway, the SDSs are in a binder in the chemical room and on the staff tablet, searchable by product name.

Every SDS has the same 16 sections in the same order, so once you know the layout, you can find information fast. The sections most useful to a worker are:

Section 4 is the one to find first in an emergency. The exact first aid for a chemical in the eyes, for example, can depend on the product. Section 8 tells you which gloves to use. Section 10 tells you what not to store it with; bleach and products containing ammonia, for example, can give off a toxic gas if they are mixed.

Manufacturers must update an SDS when they learn significant new information about the product, and employers must keep the SDSs for the chemicals they use and make them readily available on every shift.

Products with other labels

Some products in a garden center are covered by other laws instead of HazCom labeling. Pesticides are labeled under the federal pesticide law, FIFRA, which the Environmental Protection Agency administers. Consumer products used at work the same way a consumer would use them are also exempt. Workers still need to know their hazards and how to handle them safely, and Greenway's training covers them, but their labels look different. A pesticide label is a legal document: it says exactly how the product may be used, the PPE required, and how long people must stay out of a treated area.

Working safely with hazardous chemicals

Marisol finished her training with a short list of rules that apply to every hazardous chemical at Greenway:

• Read the label before you use the product, every time, even if you think you know it.
• Use only what you have been trained to use. Ask before using anything new.
• Wear the PPE the label or SDS calls for, and check that glove material matches the product.
• Never mix products unless the label says to. Some combinations give off toxic gases or can catch fire.
• Keep products in their original containers, or in a container with a proper workplace label. Never put chemicals in food or drink containers.
• Store products as the SDS says, with incompatible products kept apart, and oxidizers such as pool chemicals away from fuels and flammables.
• Keep lids closed and containers upright.
• Wash your hands after handling chemicals and before eating, drinking or smoking.
• Know where the eyewash station, spill kit and SDSs are.
• Report spills, leaks, damaged containers, missing labels and any symptoms right away.

Propane, fuel and gases

Not every hazardous product sits on a shelf. Greenway's propane cylinder cage holds dozens of 20 lb (9 kg) barbecue cylinders, and the yard stores gasoline and diesel for the chipper and loader. Propane is a flammable gas stored under pressure, so its label carries the flame and gas cylinder pictograms. It is heavier than air, which means a leak can flow along the ground and collect in low spots, drains and basements, where a spark can ignite it.

The rules for these products are strict. Cylinders are stored upright in the outdoor cage, away from doors, drains and heat, and are never brought inside the store. Only trained staff exchange cylinders, and they check the valve is closed and the cap is on before moving one. Fuel is kept in approved, labeled safety cans, and refueling is done outdoors with the engine off and cooled, with no smoking anywhere nearby. If anyone smells gas, the rule is to move people away, not to touch any switches, and to call a supervisor and, if needed, 911 from a safe distance.

Training

Under HazCom, employers must train workers before they are first exposed to hazardous chemicals, and whenever a new hazard is introduced. Training must cover the hazards of the chemicals in the work area, how to read labels and SDSs, how to detect a release, how to protect themselves, and where to find the written program. It must be in a language and vocabulary workers understand.