Boat Case Study

OH-Feel Hydroxyl Air & Surface Sanitization System

Odor Removal Case Study: Sailboats

Objective

This case study evaluates the effectiveness of OH-Feel hydroxyl technology in eliminating mold, mustiness and persistent odors on various types and sizes of boats. Testing was conducted at the Alimos Marina in Athens, Greece and Almira Shipyard at Agios Theodori, Greece using different OH-Feel hydroxyl machines, with a focus on addressing unique marine odor challenges such as mold, mildew, fuel smells, black water odors, and TVOCs.

Results by Boat

41’ Catamaran – Alimos Marina

Duration: 6 days (initial cleaning) | Nov. 13–19
Initial Condition: Strong mold/mildew odor and assorted smells.
Treatment: Initial treatment utilized the OH-Feel 500A, followed by smaller units (FC08A and CZ02) for maintenance.
Results: Odors were fully neutralized within 6 days. The cabin remained odor-free for weeks.
Comments: The FC08A maintenance unit was removed on Feb. 1. Despite unknown downtime, the boat remained fresh and odor-free as of Feb. 13. Long-term absence of having a maintenance unit will eventually allow mold and musty odors to return, but none were detected during follow-up inspections.

2. 41’ Monohull – Alimos Marina

Duration: 5 days | Dec. 7–11
Initial Condition: Exceptionally strong odors, likely from mold and black water.
Treatment: The FC08A was initially used (Nov. 13–20) but proved insufficient. The OH-Feel 500A was subsequently used for effective deep cleaning over 5 days.
Results: All offensive odors were neutralized, leaving only a residual wood scent. FC08A was installed for maintenance.
Comments: On Jan. 25, only a mild wood smell was present. Additional cleaning with a 500A was conducted due to new odors from exposed engine compartments after stair removal. Once engine work was completed, we removed the 500A machine, and the maintenance unit, and only a slight wood smell remained.

50’ Catamaran – Alimos Marina

Duration: 10 days | Jan. 25–Feb. 4
Initial Condition: Severe black water/sewage and mold odor.
Treatment: Initial treatment began Nov. 13 with CD04 and CZ02. Work was paused due to bilge leaks and resumed Jan. 25 using two 500As and a CD04.
Results: All odors were eliminated after 10 days.
Comments: On Feb. 13, a slight odor was detected due to inactive maintenance machines and was traced to mold in the HVAC system. After vent cleaning, the boat returned to an odor-free condition, confirming hydroxyl treatment efficacy.

41’ Monohull (Dry Dock) – Almira Shipyard

Duration: 10 days | Dec. 11–21
Initial Condition: Very strong and unpleasant odors—the most severe of all boats tested.
Treatment: 500A and CD04 were deployed; excellent results were observed despite the odor condition.
Results: Pungent odors were eliminated; a residual wood smell remained.
Comments: Mattress and cushion stacks in the cabin limited hydroxyl penetration on all surfaces. Follow-up on Jan. 25 confirmed only a mild wood scent. FC08A maintenance unit was purchased by the owner and effectively maintained odor control through March 27, when the vessel returned to Alimos Marina for the summer season.

51’ Cruiser Monohull (Dry Dock) – Almira Shipyard

Duration: 12 days | Dec. 21 – Jan. 2 (extended time due to holidays)
Initial Condition: Strong mold/mildew odors, worsened by water leaks.
Treatment: OH-Feel 500A and CD04 were utilized for deep sanitization.
Results: All odors were neutralized, leaving a faint wood smell.
Comments: Water leaks must be resolved prior to treatment. Maintenance with FC08A has proven effective through April 2, with no unpleasant odors detected. The initial duration was 12 days due to the shipyard being closed for the holiday season.

51’ Cruiser Monohull (Dry Dock) – Almira Shipyard

Duration: 9 days | Jan. 2–11
Initial Condition: Strong mold and mildew odor.
Treatment: OH-Feel 500A and CD04 conducted full treatment.
Results: The vessel was left odor-free with only a slight wood scent.
Comments: The owner purchased a FC08A maintenance unit which continued to keep the interior fresh through Jan. 25. No wood or chemical smells were detected.

44.9’ Sun Odyssey (Dry Dock) – Almira Shipyard

Duration: 7 days | Jan. 11–18
Initial Condition: Strong chlorine odor from cleaning agents left in sinks, toilets and showers, along with prior moldy/musty smells.
Treatment: OH-Feel 500A and CD04 were used.
Results: Complete odor neutralization achieved. A FC08A unit was installed for maintenance.
Comments: The owner purchased the FC08A maintenance unit which was left running onboard. The initial chlorine odors dissipated by Jan. 25. Upon returning to Alimos Marina in April the FC08A maintenance unit had kept the cabin smelling fresh and void of any odors.

40’ Lagoon Catamaran – Alimos Marina

Duration: 3 days | Mar. 26–28
Initial Condition: The owner complained of an unknown persistent odor in main cabin, resistant to manual cleaning and chlorine treatment.
Treatment: A 500A dual UV machine was used at air speed 3 in the main cabin.
Results: After 3 days, chlorine and mystery odors were eliminated. Only faint hydroxyl and wood scents remained.
Comments: The boat remained odor-free through April 11. The maintenance staff were impressed by the complete removal of the smell as the boat has had the nasty smell for quite some time. While the 3-day treatment was successful, a longer treatment period is generally recommended for thorough odor elimination.

Conclusion:

The OH-Feel hydroxyl technology has demonstrated strong efficacy in neutralizing a wide range of persistent odors commonly found on sailboats and cruisers—including those from mold, mildew, sewage, and cleaning agents. Across all vessels, initial overpowering odors were mitigated or fully eliminated following treatment. Long-term odor control was successfully maintained using smaller FC08A units on four of the boats. These results highlight OH-Feel hydroxyl generators as an effective, chemical-free solution for marine odor remediation—improving the onboard experience for owners and renters alike.

Note: The initial deep sanitization is typically a one-time procedure, provided the boat is then equipped with a maintenance unit. This unit should run 24/7 whenever possible—during the summer rental season and throughout winter storage—to prevent the return of mold and other odors.

Interested in similar results for your yacht or charter fleet? Contact us for a free consultation.

Contact Us:

Website: www.ohfeel.gr

Email: info@ohfeel.gr

Telephone: +30 693 275 6720