Lead wool is well known in the industrial sector. This material is often used to seal around flanges, connections, and pipes. It can also be found in apertures within walls and ceilings when there may be an abundance of radiation from equipment as the lead wool protects certain areas. Another industry where lead wool is used is in the medical industry, as it can be found in medical O2 sensors.
What is Lead Wool?
Lead wool is a chemical grade lead. It is stretched and drawn into thin, long strands that are very fine. To make the lead wool, a lead disc will be scratched, as the strands are created into the desired sizes and lengths. The strands can also be twisted into 5/8″rope for various applications.
There are many advantages to lead wool. This material, when used as caulking and waterproofing, can prevent leaks while withstanding immense pressures. Lead wool can also be used to protect medical workers when using x-ray equipment as it reduces the amount of radiation that passes through when acting as a shield.
Lead Wool in Medical O2 Sensors
Medical O2 sensors are used to measure the oxygen saturation in the body or within the blood. Most medical O2 sensors that patients are aware about are electrochemical sensors used to test the blood when a person is undergoing cardiac surgery. Patients may also use a personal blood glucose monitor to determine their glucose levels.
Another type of medical O2 sensor is an infrared oxygen sensor. These sensors are placed onto a finger or even the earlobe. The sensor uses pulsating red and infrared light to measure the amount of oxygen saturation in the body based on how the skin absorbs the light. It checks the oxygenated hemoglobin in the blood arteries.
A third type of medical O2 sensor is an electro galvanic sensor. These sensors act as a fuel cell. The cells have an anode containing lead and a cathode consisting of a noble metal such as gold or platinum. There is also an electrolyte that bathes the internal sensor components. The oxygen will become diffused into the sensor and becomes hydroxyl ions on the cathode. The hydroxyl ions oxidize the lead anode to generate the electrical current.
Medical O2 Sensors for Ventilators and Respirators
The medical O2 sensors typically used for ventilators and respirators are electro galvanic fuel cell sensors. The lead wool located in the sensor acts as a working electrode as the fine stands provides the appropriate area-to-volume surface ratio. The oxygen molecules can thoroughly access the lead wool, versus a large block of lead that can prevent the oxygen from moving about.
In time, the hydroxyl ions convert the lead wool into lead oxide as the lead wool becomes consumed. The lead wool in the sensor can last up to 2 years, but may be less based on the temperature of the atmosphere that can impact the fuel cell output rate.
Demand for Ventilators and Respirators
Due to the current demand for respirators and ventilators because of the Covid-19 pandemic, the need for operational medical O2 sensors has also increased. Medical O2 sensors must be carefully manufactured to ensure that the lead oxide created from the lead wool does not leak from the device during operation. Manufacturers also require a steady supply of lead wool from trusted suppliers to meet production runs and time to delivery schedules.
Here at Belmont Metals, we offer lead wool twisted into 5/8″ rope. It is certified to meet Federal QQ-C-40 specifications for lead wool and lead pig materials. For more information about our metal products, contact our company today.