Starting a hull-cleaning business in California

Why the rules exist: copper paint

Most bottom paint on California boats releases copper to keep growth off. The state Department of Pesticide Regulation found that passive leaching and in-water hull cleaning are the main ways that copper gets into marina water, and that aggressive cleaning raises leaching for weeks afterward. Its study found cleaning with best management practices (BMPs) put less copper in the water than cleaning without them.^[1] Since July 1, 2018, copper paints labeled for recreational boats have been capped at a leach rate of 9.5 µg/cm²/day. DPR also says it has no authority to regulate or license in-water hull cleaners.^[1] That's why the rules are local.

Three harbors have regional copper limits (TMDLs) that name hull cleaning: Shelter Island Yacht Basin in San Diego Bay^[2], Marina del Rey^[3] and Newport Bay.^[4]

Hull-cleaning rules by harbor

Sources: Port of San Diego^[5][6][7]; Los Angeles County^[8]; Santa Barbara^[9]; Long Beach.^[10] Every harbor we researched is in the vendor requirements table.

San Diego Bay in detail

No business may clean hulls in the water in San Diego Bay without the Port permit, and each marina must see proof of it before letting you work. Zinc changes and work on running gear and through-hulls are not counted as hull cleaning.^[6]

Marina del Rey in detail

Get access to the free online BMP training by emailing TMDL@bh.lacounty.gov. The Commercial Services ID is issued at the Sheriff's Marina Station on the third Tuesday of each month, 7 to 10 a.m.; bring a photo ID and your diver certification card. With your ID and BMP certificate, book an appointment with the Boating Section to get the burgee. Boat owners can be cited for hiring an uncertified cleaner.^[8]

Cleaning practice harbors expect

• Wait after new bottom paint. Long Beach and Sacramento Marina both say 90 days.^[10][11]
• Use the least abrasive pads^[10], and stop if you see a paint plume: a visible plume is prohibited in Marina del Rey and San Diego Bay.^[8][6]
• No underwater sanding or stripping.^[11]
• Keep a record of each clean: paint age, tool, plume check, zincs.

The hull cleaning log records all of that and flags cleanings inside 90 days of new paint.

Dive certification and BMP training

The harbor rules we found ask for "a diver certification card" without naming a level, plus BMP training. A harbor's card check is not diving safety training; see diving safety below.^[8] The California Professional Divers Association developed the industry's in-water hull cleaning BMPs and ran certification courses across the state for years.^[13] We could not find a current CPDA course schedule. The state Boating Clean and Green program publishes a hull cleaning factsheet for boaters and cleaners.^[12] The LA County online course is the most accessible current program we found.

See how to become a hull diver for training paths.

Diving safety: certification, harbor rules and workplace rules

1. Recreational scuba certification

A card from PADI, NAUI, SSI or a similar agency shows you were trained for recreational diving: PADI's Open Water card, for example, qualifies you to dive with a buddy to 18 meters (60 feet).^[27] Some harbors ask to see a diver card before issuing an ID (see below). A recreational card is not training for working dives, and on its own it doesn't show the training the workplace diving rules call for.

2. Harbor and permit requirements

Harbors regulate who may clean hulls in their water and how, mostly to limit copper pollution: the Port of San Diego's hull-cleaning permit and BMP training form, Marina del Rey's Commercial Services ID with a diver card and BMP certification, and Santa Barbara's BMP training. These rules are about access and water quality. None of them sets diving safety practices, and meeting them doesn't mean a crew meets the diving safety rules.

3. Workplace diving rules (when divers are employees)

Cal/OSHA's Diving Operations orders (Title 8, Article 152, §§6050–6058, amended effective January 1, 2026) apply to all diving operations in California, with exemptions for instruction, public-safety, human-research and scientific diving.^[14][15] They define commercial diving operations as diving in which “repair, maintenance” or ship repair work is performed.^[16] Hull cleaning isn't named, but it reads as maintenance; Cal/OSHA hasn't said so publicly that we found. Federal OSHA's commercial diving standard (29 CFR 1910 Subpart T) covers the same ground for places of employment.^[21] For employers, the California rules require:

• A written Manual for Diving Safety at the dive location, with emergency procedures and contact numbers for the nearest recompression chamber and medical facilities, and a person in charge at the dive location.^[17][19]
• Divers who are “trained and qualified for the diving mode being used,” and every dive team member trained in CPR, diver rescue techniques and diving-related first aid. A first-aid kit and a bag-type manual resuscitator at the site.^[17][22]
• For scuba: a standby diver available while a diver is in the water; each diver line-tended from the surface or accompanied by another diver in effective communication; line-tending in enclosed or physically confining spaces; no deeper than 130 feet.^[20][23]
• Hookah (surface-supplied air through a hose from a compressor, common in hull cleaning): the California text reads “Hookah diving shall be permissible only during zoo and aquarium exhibit diving and film and TV diving operations,” and requires a separate team member tending each hookah diver's hose.^[20] If your crew uses hookah, ask Cal/OSHA how this applies to hull cleaning before anyone dives.
• A record of each dive operation, kept for at least a year,^[17] and a current physical exam for each dive team member, repeated yearly.^[18]

Who is covered. These duties fall on employers. Federal OSHA says self-employed workers are not covered by the OSH Act,^[24] and the California rules define a diver as “an employee.”^[16] So a sole proprietor diving with no employees appears to be outside them. Once anyone works for you, whether a second diver or a tender on the dock, expect them to apply; calling that helper a contractor doesn't settle it under California's ABC test. Whether partners or co-owners who dive together are covered is not clear from the text.

Commercial diver training. There is no commercial diver license in the United States. The rules require training and qualification for the work rather than a named school; OSHA has accepted a commercial diving school certificate, an ADCI card, or documented training to the ANSI/ACDE-01 consensus standard as ways to show it.^[25] If you employ divers, you need to be able to show each one is trained and qualified for the diving you do.

The business side

• Insurance: make sure your policy covers working dives and the boats you're cleaning. Some marine trades programs list underwater hull cleaning as an eligible trade.^[28] See the insurance guide.
• Seller's permit: if you bill zincs separately, you are the retailer of them.^[29]
• Licenses: a business license in each harbor's city, plus the harbor permits above. See the startup guide.
• Pricing: the hourly rate calculator and route planner help you price per foot.