Hazardous Materials and Waste Management
Domain 4 tests how organizations inventory, label, store, use, and dispose of hazardous materials and waste. Expect questions on OSHA Hazard Communication, safety data sheets, secondary container labeling, biomedical waste, RCRA hazardous waste, spill response, and special hazards such as formaldehyde, mercury, and chemotherapy agents.
Core rules
- OSHA HazCom requires a written program, chemical inventory, safety data sheets accessible to workers, labels, and training. Secondary containers must be labeled unless used immediately by the person who filled them.
- Biomedical waste such as blood-soaked items and sharps goes in red bags or sharps containers; regular trash must not be contaminated. Sharps containers are closed when about three-quarters full.
- Hazardous waste follows RCRA and DOT rules: identification, accumulation, labeling, manifests, and trained handlers. Never pour chemicals down the drain unless authorized.
- Spill response includes evacuating, protecting responders, using the spill kit, containing, cleaning, and reporting. Mercury spills require special cleanup, not a standard mop.
- Store oxidizers away from flammables; keep cylinders secured and upright; separate incompatible chemicals.
Worked example
A housekeeper fills an unlabeled spray bottle with disinfectant for a quick task. The correct action is to stop, label the container with the product name and hazard, and use it only for the intended task. If the chemical is transferred for another shift, the label and SDS access are required. If the product is a hazardous waste when discarded, it must not go in regular trash.
Traps
Do not put all waste in red bags; over-classification increases cost and is noncompliant. Never mix bleach with ammonia or acid. Do not assume an SDS is only an office document; workers must be able to access it without delay.