🔍 Key Concepts

• 33 CFR Part 159 – Marine Sanitation Devices (MSDs) • Definition and performance standard for a Type I MSD versus Type II • Units of measurement: coliform count per 100 milliliters and suspended solids (mg/L)

💭 Think About

• Focus on which options are using the correct test volume: does 33 CFR express the bacteria limit per 100 mL or per 1000 mL? • Ask yourself: for Type I devices, is the standard stricter (lower bacteria count) or more lenient than Type II? That will help you compare the numbers 200 vs. 1,000. • Look at which answer choices mention suspended solids. Does 33 CFR require a suspended solids limit for Type I, or is that only specified for another type of MSD?

✅ Before You Answer

• Check 33 CFR 159 to confirm the exact phrase for Type I: look for "fecal coliform" and the phrase "per 100 milliliters". • Verify whether Type I performance standards include a requirement for "no visible floating solids" or a numerical suspended solids limit. • Be sure you match BOTH parts of the standard correctly: the coliform count AND whether it mentions floating solids or suspended solids.