1. Personal Protective Equipment (PPE)
The hierarchy of controls dictates that PPE is the last line of defense, not the first. However, it is the most visible and consistently enforced safety measure.
- Eye Protection: ANSI Z87.1 approved safety goggles with indirect venting are required when handling liquids. Safety glasses with side shields are acceptable only for dry solids or when specifically approved by the PI.
- Lab Coats: Must be 100% cotton or a flame-resistant (FR) material (e.g., Nomex). Synthetic materials like polyester will melt into the skin upon exposure to fire.
- Gloves: Nitrile is the standard for general use, but it is not universally impenetrable. For example, dichloromethane (DCM) permeates standard nitrile in less than 3 minutes. Always consult a chemical compatibility chart for specific reagents.
2. Hazard Communication & SDS
Safety Data Sheets (SDS), formerly MSDS, are standardized under the Globally Harmonized System (GHS). You must know the location of physical or digital SDS for every chemical in your inventory.
The GHS Pictograms You Must Know
3. Chemical Storage Segregation
Alphabetical storage is a recipe for disaster. Chemicals must be segregated by hazard class to prevent incompatible reactions during a spill or fire.
| Storage Group | Incompatibilities | Examples |
|---|---|---|
| Flammable Liquids | Oxidizers, Corrosives | Acetone, Toluene, Hexane |
| Oxidizers | Flammables, Organics | Nitric Acid, Peroxides |
| Acids | Bases, Cyanides, Sulfides | HCl, H₂SO₄ (Store Nitric separately) |
| Bases | Acids | NaOH, KOH, Ammonia |
4. Emergency Procedures
When an incident occurs, hesitation compounds the damage. Memorize the locations of the safety shower, eyewash station, spill kits, and fire extinguishers.
- Chemical Exposure (Skin/Eyes): Immediately flush the affected area for a minimum of 15 minutes. Do not rub your eyes. Seek medical attention immediately after flushing.
- Fires: Do not attempt to fight a fire unless it is small (trash can sized), you are trained, and you have a clear exit path. Use the PASS method: Pull, Aim, Squeeze, Sweep.
5. Waste Disposal
Improper waste disposal violates federal EPA regulations (RCRA) and can result in massive institutional fines or environmental damage.
- Never pour hazardous chemicals down the drain.
- Halogenated and non-halogenated organic solvents must be collected in separate, clearly labeled containers.
- Aqueous waste must be neutralized (pH 6-8) before disposal, only if institutional policy permits drain disposal of the specific neutralized salt.