🔍 Key Concepts

• Three types of Marine Sanitation Devices (MSDs) and how they differ (Type I, II, III) • The difference between treating sewage vs storing or preventing discharge • Relevant pollution regulations in 33 CFR Part 159 – Marine Sanitation Devices

💭 Think About

• Look at which answer choices talk about water quality standards (bacteria counts and solids) versus those that talk about stopping discharge altogether. • Ask yourself: Does a Type III device treat and discharge effluent, or does it mainly hold or block sewage from going overboard? • Which types (I, II, or III) are associated with specific fecal coliform limits and solids in the effluent?

✅ Before You Answer

• Verify in 33 CFR 159 which MSD type is defined as a holding tank or device that prevents overboard discharge. • Confirm which MSD types (I or II) have specified fecal coliform bacteria and solids limits in their performance standards. • Before choosing, be sure the requirement you select matches the correct type number (I, II, or III), not just something that sounds environmentally strict.