Machinist’s Mate’s Exposure to Asbestos

Machinist’s Mates were assigned to the engine rooms and auxiliary machinery spaces for training, watch-standing, and maintenance duties. These spaces contained vast amounts of asbestos insulation that covered pipes, valves, equipment, and machinery. The Machinist’s Mate was responsible for the operation and maintenance of this equipment and was heavily exposed to asbestos on a daily basis. Machinist’s Mates also spent time each day in the ship’s public spaces, the galley, berthing areas, and lounge areas, where all the crew members congregated and where they experienced additional exposures to asbestos.

Machinist’s Mates were exposed to asbestos through their normal maintenance duties, during their watch-standing assignments, and as they lived and worked in the closed and confined shipboard environment where asbestos insulation was ubiquitous. Machinist’s Mates breathed asbestos dust and were unaware of its dangerous properties. As a result, men who served in the Navy as Machinist’s Mates are at risk of contracting mesothelioma or other asbestos-related diseases.

Routine Maintenance of Asbestos Insulated Equipment

Machinist’s Mates performed all routine, scheduled maintenance and corrective repairs for the machinery systems and equipment within the engine room, the auxiliary machinery spaces, and throughout the ship. Especially during wartime and training exercises, where the engineering plant was being exercised to its limits and damage was likely, it could easily have been the case that a Machinist’s Mate spent another six to eight hours each day, in addition to his watch-standing duties, doing preventive maintenance and corrective repairs.

Often the extent of needed maintenance and repairs required that a boiler or even an entire engine room be shut down and cooled down for maintenance. During such periods, an “all hands” effort ensued to accomplish the maximum amount of work in the minimum amount of time. During coordinated efforts such as these, it was quite likely that large amounts of asbestos insulation, asbestos gasket and asbestos packing removals and replacements were performed on pumps, valves, piping, and equipment.

In shipboard steam propulsion plants, very significant changes in space temperature control resulted from apparently minor insulation damage and valve and pump packing leakage. Therefore, when the opportunity arose, it was essential to fix as many leaks as possible. Often the “cold iron work list” included a very large number of valves that required repacking, necessitated the removal of asbestos pads covering the valves and then the existing asbestos ring-type packing and installation of new asbestos packing.

Asbestos Exposure

While Watch-Standing

A Machinist’s Mate within the Engineering Department was assigned to various watch stations principally within the engine rooms, such as Turbo-generator Watch, Distilling Plant Watch, Feed Pump Watch, or Main Engine Watch. Being so assigned, he was responsible for the operation of the equipment at his watch station during four-hour intervals. A Machinist’s Mate was expected to spend at least eight hours per day on watch, operating the various equipment and systems associated with an engine room. These extended watches occurred in the spaces where asbestos insulation was routinely disturbed and released asbestos dust into the air these crewmen breathed as they stood watch and operated the equipment.

During Technical and Military Training

Although it might at first seem that training time would not have presented any significant risk of asbestos exposure, such was not the case in the Engineering Department of a destroyer at war. For Machinist’s Mates, training most often consisted in creating or simulating unusual engineering situations such as infrequent equipment operations, unusual operating modes, or major damage scenarios, and generally stressful situations, both to the personnel and to the equipment. The increased shock and vibration resulted in the shaking and jarring of asbestos insulated equipment, as did the inadvertent damage by contact as the crew quickly moved about in very tight spaces to respond to the training scenario. Such activity served to release asbestos particulates into the air, invisibly increasing the asbestos fiber content of the air that the crew breathed. This presence of airborne contamination was often exacerbated when training scenarios involved shutting down ventilation systems.

In Common Areas

The engineering systems traveled the length and breadth of the ship, including berthing, messing and lounging areas that a Machinist’s Mate occupied during off-duty hours. The domestic hot water system, for example, consisted of asbestos-insulated piping that traveled to every berthing, sanitary and messing space. In fact, most, if not all, spaces aboard the ship contained asbestos-insulated piping, asbestos-gasketed joints, and valves with ring-type asbestos packing. A Navy ship at sea was in constant motion due to wind, sea motion, and the internal vibration caused by rotating machinery. The shock of guns firing, heavy rolls while maneuvering, during training or actual close hostile fire situations added significantly to the airborne asbestos contaminants the crew was forced to continuously breathe.

Machinist Mate’s Heavy Exposure to Asbestos

Direct exposure to asbestos dust occurred while a Machinist’s Mate was involved in the routine engine room watch-standing and in the operation, maintenance and repair of engineering equipment, such as turbines, pumps, compressors, and the associated piping and valves. Hot water and steam-piping pervaded the engineering spaces where he served his working hours. Hot water and steam-heating piping also traversed the berthing spaces for which he was assigned cleanliness responsibilities, and the mess decks, where the crew ate and gathered for social functions and entertainment.

Shipboard piping systems typically utilized portable removable asbestos pads over valves and other components subject to periodic maintenance and repair access. As a crewman in M Division, a Machinist’s Mate frequently came into contact with the asbestos debris where insulation had been disturbed, either through the normal conduct of personnel traffic and activity, being bumped or damaged during some incident or proximate repair work, or the physical shock from ship’s motion while in heavy seas or during gunfire actions. Another aspect of routine maintenance that cannot be overlooked in terms of asbestos exposure was the periodic and post-repair work-space cleanup responsibilities.

On a daily basis, Machinist’s Mates were also exposed to the asbestos dust and debris carried amongst crew members on their bodies, their clothing and their tools and equipment. All of the crew was exposed to asbestos dust that was generated from all industrial activities and carried throughout the ship since they ate and slept in the same spaces.