QuietScoreBathroom & Utility Fans › Delta SMT150D

Delta SMT150D noise level

The Delta SMT150D is certified at 0.3 sones (≈23 dBA) — quieter than 75% of the 811 bathroom & utility fans in the ENERGY STAR database. In practical terms it is near the threshold of human hearing — effectively silent in a normal room.
0.3sones (certified)
≈23 dBAapproximate conversion
150 CFMairflow
8.9CFM per watt

The Delta SMT150D is quieter than the category median of 0.7 sones, and its 150 CFM rating makes it suitable for bathrooms up to roughly 150 sq ft.

Full specifications

BrandDelta
Model numberSMT150D
Model nameBreezSmart
CategoryBathroom & Utility Fans
Sound level0.3 sones (≈23 dBA, approximate)
Airflow150 CFM
Efficiency8.9 CFM/W
Duct size6 inch diameter
Speeds3
Integrated lightingNo
ENERGY STAR certifiedYes
On market since2016-12-26
MarketsUnited States, Canada

Quieter alternatives with similar airflow

Model Sones ≈ dBA Airflow Efficiency
Air King EVD 0.1 7 150 CFM 4.5 CFM/W specs
Air King EVDG 0.1 7 150 CFM 4.5 CFM/W specs
Air King EVDGH 0.1 7 150 CFM 4.5 CFM/W specs
Air King EVDH 0.1 7 150 CFM 4.5 CFM/W specs
Air King EVLD 0.1 7 150 CFM 4.6 CFM/W specs

Similar bathroom & utility fans

Model Sones ≈ dBA Airflow Efficiency
Air King E110S 0.3 23 150 CFM 4.5 CFM/W specs
Air King E130S 0.3 23 150 CFM 4.5 CFM/W specs
Air King E130SH 0.3 23 150 CFM 4.5 CFM/W specs
Broan QTXE110150DC 0.3 23 150 CFM 11 CFM/W specs
Broan QTXE110150DCL 0.3 23 150 CFM 11 CFM/W specs

Frequently asked questions

How many sones is the Delta SMT150D?

The Delta SMT150D is certified at 0.3 sones in ENERGY STAR lab testing, which is approximately 23 dBA. That is near the threshold of human hearing — effectively silent in a normal room.

Is the Delta SMT150D quiet?

At 0.3 sones, the Delta SMT150D is quieter than 75% of the 811 certified bathroom & utility fans we track, and quieter than the category median of 0.7 sones.

How powerful is the Delta SMT150D?

It moves 150 CFM, which is adequate for a bathroom of roughly 150 sq ft under the standard 1-CFM-per-square-foot guideline, at an efficiency of 8.9 CFM per watt.

Data provenance: Sound levels are certified lab measurements (sones) reported in the U.S. EPA ENERGY STAR certified products dataset — not manufacturer marketing claims. Source: ENERGY STAR Certified Ventilating Fans (US EPA), last fetched 2026-06-13. The dBA figure is an approximate conversion from sones — see our methodology.