IMO noise rules aren’t enough to protect mariners’ hearing

I had just finished a four-day temporary job as a deck hand on a combination towing vessel/landing craft, working for a large West Coast company out of Long Beach, Calif. It was my first job after graduating from the California Maritime Academy, and I was relieved when the port captain said that there would be a place for me on a different boat in the near future, and to check in with him in a couple of weeks. While waiting for my first paycheck to arrive, being from Spokane, Wash., and not Southern California, that meant I had no place to stay and not enough money for an apartment or a motel. Like manna from heaven, the father of a friend of mine from school came to my rescue. A stationary engineer at a local university when I met him, Tom had sailed for years in the U.S. merchant marine, having worked his way up from wiper to first engineer. He and his wife Jean kindly offered me a spare bedroom at their family home in Santa Ana until I got on my feet financially. One night after dinner we were talking about his career on the water, and being a deck type I asked if he had any regrets about choosing to be an engineer. Pointing to his hearing aids he replied, “Just one. I wish I could get my hearing back.”
A 2008 Danish study confirmed that not only is noise-induced hearing loss a leading occupational hazard of going to sea, but many merchant mariners are at high risk for developing it — especially those working in the engine room. A research report prepared for the U.S. Coast Guard in 1979 measured the noise level on various commercial vessels and found that the main engine spaces of every U.S.-flag ship tested commonly exceeded 100 decibels — with one measuring 115 decibels. According to the National Institute on Deafness and Communication Disorders, regular exposure to 110 decibels for a minute or more can cause permanent hearing loss. The 1979 Coast Guard report also found that open bridge wing noise on some of the ships tested measured 90 decibels or more. A National Institutes of Health report noted that people who spent their workdays in areas where noise levels exceeded 85 decibels had a 300 percent greater chance of permanent hearing loss as a result.

For decades both designers and operators of commercial vessels seemed to have little awareness of the debilitating effects ship noise levels had on mariners. I remember one of the first tugs I worked on had an able seaman’s “room” that was right below the windlass up forward. I actually got used to it turning loudly just inches above my head nearly every night for my entire one-month work tour. By the time I got home on vacation I was so desensitized to noise that I slept though an earthquake one morning. Glass and other items came crashing down all around me, as our dog barked and my wife yelled and screamed from the doorway trying to awaken me.

In 1981 the International Maritime Organization (IMO) passed Resolution A468XII-1981. It included various guidelines and recommendations designed to help reduce noise levels on vessels at sea, and it placed limits on the maximum noise in certain shipboard areas. Unfortunately the resolution only addressed large oceangoing ships, with all the guidelines, recommendations and noise limits being strictly voluntary, thus easily ignored by many in the maritime industry.

In 2014, finally acknowledging that a life working at sea can have a detrimental effect on hearing, the IMO amended the International Convention for the Safety of Life at Sea (SOLAS) to include the Code on Noise Levels Aboard Ships, new mandatory noise rules for some commercial vessels. The maximum levels for different areas on board are no longer guidelines, but have been formally established for commercial vessels over 1,600 gross tons built after July 1, 2014. Ship operators must provide adequate instruction on how to reduce hearing loss, make personal hearing protection available to all crewmembers and establish a “Hearing Protection Plan” for mariners who spend most of their onboard work hours in extremely noisy areas — to include acoustic monitoring of ship spaces and hearing tests/checkups.

Though definitely an improvement over the voluntary guidelines of the past 30-plus years, in my opinion the new SOLAS noise rules are just a good first step and nothing more. They completely exempt huge numbers of newbuilds including mobile offshore drilling units, fishing industry vessels and dredges. In addition, all vessels over 1,600 tons constructed before July 1, 2014, are completely exempt from the new regulations. These exemptions include tens of thousands of vessels, with hundreds of thousands of mariners. I think that the new SOLAS noise rules for ships should apply to all commercial vessels over 300 gross tons, existing ships and newbuilds included. In addition, monitoring and hearing protection programs should be mandated for every one of those vessels, with noise reduction retrofitting required for any shown to have levels in excess of current IMO regulations.

The lack of concern the maritime industry has shown toward protecting mariners’ hearing has taken its toll on the health of many men and women over the years. Today, however, hearing loss is more than a health issue — it can have serious career consequences as well. In accordance with Navigation Vessel and Inspection Circular 4-08, U.S. Coast Guard regulations require U.S. merchant mariners to meet a minimum hearing standard to obtain/upgrade/renew a merchant mariner credential. Those who can’t meet the standards because of deafness face being medically disqualified from working — possibly forever. What I find most cruel is that the same mariners who could be permanently prohibited from sailing because they are deaf may have gotten that way working on commercial vessels in the first place. It’s nice that the new IMO Noise Code rules have finally come into effect, but they are not enough.

Till next time, I wish you all smooth sailin.’

Kelly Sweeney holds the licenses of master (oceans, any gross tons) and master of towing vessels (oceans), and regularly sails on a wide variety of commercial vessels. He lives on an island near Seattle. You can contact him at

By Professional Mariner Staff