Environmental and chemical safety basics: carbon footprint, hazardous waste and storing chemicals safely

Environmental and chemical safety rest on a few basics: knowing your carbon footprint, reading hazard labels, storing chemicals correctly and handling waste properly. This guide explains each topic in plain English so EHS teams can see what to measure, what to label and what to control.

What is a carbon footprint?

A carbon footprint is the total amount of greenhouse gas emissions caused by an organization, a product or an activity. It is usually expressed in metric tons of carbon dioxide equivalent (CO2e), which converts gases such as methane and nitrous oxide into the equivalent amount of carbon dioxide.

The three scopes of emissions

Scope	What it covers	Examples
Scope 1	Direct emissions from sources the organization owns or controls	Gas boilers, company vehicles and on-site fuel use
Scope 2	Indirect emissions from purchased energy	Electricity, steam, heating and cooling
Scope 3	All other indirect emissions in the value chain	Purchased goods, business travel, commuting, transport, waste and use of sold products

How to calculate a carbon footprint

• Set the boundary: decide which sites, activities and years are in scope
• Collect activity data: fuel used, electricity consumed, distance traveled and waste produced
• Apply emission factors: published figures that convert each activity into CO2e
• Add up the results by scope and source
• Check data quality and note assumptions
• Repeat on a regular schedule to track change

Most organizations use the Greenhouse Gas Protocol as the standard method. Reporting rules differ by country. In the UK, for example, some companies must report energy use and carbon under Streamlined Energy and Carbon Reporting (SECR). Check the rules that apply to your organization.

Reducing a carbon footprint

• Measure first, so you know the biggest sources
• Cut energy use through efficiency and better controls
• Switch to lower-carbon energy where possible
• Review travel, logistics and procurement choices
• Set a target and assign owners
• Report progress and update the plan

Hazard symbols and labels

Hazard symbols and labels tell people what risks a chemical carries before they open a container. Under the Globally Harmonized System (GHS), labels follow a common format across countries that have adopted it.

What a GHS label includes

• Product identifier: the chemical name or code
• Signal word: Danger for more severe hazards or Warning for less severe ones
• Hazard statements: standard phrases describing the hazard
• Precautionary statements: advice on prevention, response, storage and disposal
• Pictograms: red-bordered diamond symbols showing the type of hazard
• Supplier details: name, address and phone number

Common GHS pictograms

Pictogram	Meaning
Flame	Flammable materials, self-heating substances and some organic peroxides
Flame over circle	Oxidizers that can intensify fire
Exploding bomb	Explosives and self-reactive substances
Gas cylinder	Gases under pressure
Corrosion	Corrosive to skin, eyes and metals
Skull and crossbones	Acute toxicity that can be fatal
Exclamation mark	Irritation, skin sensitization and acute toxicity of lower severity
Health hazard	Carcinogens, respiratory sensitizers and organ toxicity
Environment	Hazardous to the aquatic environment

If you transfer a chemical to another container, label the new container as well. Read the safety data sheet for full details, because the label is only a summary.

How to store chemicals safely

Safe chemical storage prevents fires, toxic releases and reactions between incompatible products. The right method depends on what you hold, so start from the safety data sheet and your chemical inventory.

Core storage rules

• Keep an up-to-date inventory so you know what is stored and where
• Store chemicals in their original containers with labels intact
• Separate incompatible chemicals, such as acids from bases and oxidizers from flammables
• Use purpose-built cabinets for flammable and corrosive materials
• Keep storage areas cool, dry and ventilated, and away from heat and ignition sources
• Store heavy containers low and never above eye level
• Use secondary containment, such as bunds or trays, to catch leaks
• Keep spill kits, eyewash and fire extinguishers close by
• Limit access to trained people and keep storage areas locked where needed
• Inspect storage regularly for leaks, damage and expired stock

Example segregation

Chemical group	Keep away from
Flammable liquids	Oxidizers, heat and ignition sources
Acids	Bases, cyanides and reactive metals
Bases	Acids
Oxidizers	Flammables, combustibles and reducing agents
Water-reactive materials	Water and moisture

This table gives general examples. Always check the safety data sheet for specific incompatibilities.

What is hazardous waste?

Hazardous waste is waste that can harm people or the environment because of its chemical, physical or biological properties. It can be a liquid, solid or gas, and it often comes from ordinary activities such as cleaning, maintenance, manufacturing and laboratory work.

Common types of hazardous waste

• Solvents, paints and thinners
• Acids, alkalis and corrosive cleaners
• Oils and oily rags
• Batteries and electronic waste
• Fluorescent lamps
• Chemical containers with residue
• Asbestos and contaminated materials
• Healthcare and laboratory waste

Definitions and categories vary by country. In the UK, hazardous waste has its own classification and consignment note rules. In the US, the Resource Conservation and Recovery Act (RCRA) defines hazardous waste and sets generator categories. Check local law for your sites.

Handling hazardous waste safely

• Identify and classify the waste at the point it is created
• Keep different waste types separate and do not mix hazardous with non-hazardous waste
• Use suitable, labeled and sealed containers
• Store waste in a secure area with containment
• Limit how long waste stays on site according to the rules
• Use licensed carriers and permitted disposal sites
• Keep records, including waste transfer or consignment documents

Waste management basics

Waste management is the set of steps that control waste from where it is created to its final disposal. Most good programs follow the waste hierarchy, which ranks options from best to worst for the environment.

Step	Meaning	Example
Prevent	Avoid creating waste	Order only what you need
Reuse	Use items again	Refill containers
Recycle	Turn waste into new material	Metal, glass, paper and some solvents
Recover	Recover energy or other value	Energy from waste
Dispose	Landfill or incineration without recovery	Last resort

Waste management in practice

• Know what waste you produce: audit streams and volumes
• Set targets for waste reduction and recycling
• Provide clear bins and signage
• Train staff on segregation and handling
• Track waste with records and data from carriers
• Review contractors and disposal routes
• Report waste data alongside other environmental measures

Waste data often sits alongside carbon, energy and permit data, and teams spend a lot of time pulling it together. Ideagen environmental management software gives teams one place to track environmental data and tasks, so they can see performance and follow up on actions. Staff still need to make the day-to-day decisions on how waste is handled.

Frequently asked questions

What is a carbon footprint in simple terms?

It is the total greenhouse gas emissions caused by a person, organization, product or activity, measured as CO2e.

What are Scope 1, 2 and 3 emissions?

Scope 1 is direct emissions. Scope 2 is emissions from purchased energy. Scope 3 is all other indirect emissions in the value chain.

What do hazard pictograms mean?

They are standard symbols on chemical labels that show the type of hazard, such as flammable, corrosive or toxic.

Can I store all chemicals together?

No. Incompatible chemicals can react dangerously, so separate them based on the safety data sheet.

What counts as hazardous waste?

Waste with properties that can harm people or the environment, such as solvents, corrosive cleaners, batteries and contaminated materials. Definitions differ by country.