MarShield™ Offers Sheet Lead for Many Applications Including:
MarShield™ provides Sheet Lead with a consistent and high density manufactured from pure lead conforming to ASTM B-29, B-749 and Federal QQ-L-201F, QQ-L-171E. We use only the purest lead available. Our sheet lead is 99.94% pure lead. Absolutely no refining is performed in the manufacturing of our sheet lead. MarShield™ is only interested in providing its customers with the highest quality sheet lead available in the market place today.
THE VERSATILITY OF SHEET LEAD AND ITS USES
With sheet lead being the most malleable of common metals it can be easily shaped, formed, bent and/or easily cut to suit all applications. Our sheet lead is extremely resistant to corrosion from the atmosphere, salt water, and most industrial chemicals. It is ideal for making corrosion-resistant gaskets, lead lining tanks, reducing sound in rooms and replacing metal flashing in roofs. With its high density and flexibility it becomes superior in shielding rooms from radiation against x-rays and gamma radiation. Sheet lead is built into a variety of structures, such as walls, doors, window frames and cabinetry to provide the necessary shielding protection. In waterproofing applications the sheet membranes are installed on-site, then burned (welded) with same-composition lead burning bar to affect, a long-lasting, impermeable barrier. With its high "limpness" (low stiffness) and high internal damping capacity it becomes excellent barrier material to block the transmission of sound, and for isolating equipment from mechanical vibration.
Since sheet lead can easily be shaped with little effort at ambient temperatures without the need for periodic softening or annealing it does not work harden. It therefore can be readily manipulated with standard hand tools without the risk of fracture.
As with most other commodities, sheet lead is usually sold by the pound and is available in rolled or sheet form.
MarShield™ stocks the most common four thickness as follows:
Our stock sheets are available in sheet sizes 48" wide x 120" long (1219.2 mm wide x 3048 mm long) or 48" x 96" (1219.2 mm wide x 2438.4 mm). For the convenience and cost savings in freight the three smaller sizes are sold in rolled form and the larger size is in flat sheet form.
MarShield™ offers sheet lead as laminated panels, adhesive bonded to such materials like plywood, gypsum board, and other supporting materials. Since sheet lead has very little inherent structural strength, most applications require that the Sheet Lead be supported in some fashion, or that the sheet lead be laminated to provide a more rigid building material. This type of shielding is found in hospitals, medical and industrial x-ray installations.
Since sheet lead can't suit all applications because the appropriate sizes are not always available, then MarShield™ will manufacturer cast lead radiation shielded products and assemblies. We have the capabilities of casting lead from simple blocks to complex nuclear shielding applications. Working with our customers requirements MarShield™ will create all the necessary tooling or molds to make that one-of-a-kind cast shielding product. MarShield™ offers quick turnaround time on all sheet lead. With its large warehouse of sheet lead most orders can be shipped out on the same day.
LEAD LINED DRYWALL/GYPSUM BOARD OR PLYWOOD INSTALLATION GUIDELINE
We start out by using only fire code gypsum materials for all lead lined drywall/gypsum products. The drywall should conform to ASTM C36. Lead lining from 1/32" - 1/16" and if necessary 1/8" although not recommended due to the heavy weight and handling. A recommended thickness of a single unpierced sheet of Lead in any chosen length is applied and bonded to the appropriate length of drywall/gypsum board. The drywall/gypsum boards are available in a minimum size of 4' x 8' to a maximum 4' x 10' x 5/8" minimum thickness. 1/2" thick drywall is available but not recommended.
Install leaded side of drywall/gypsum board, lath or plywood that will be used to cover the sheet lead against wooden or metal studs ensuring that you match the joints of the sheet lead used. Material must be in a vertical position with joints running from floor to ceiling as required by standards. Drill pilot holes as necessary to prevent deformation of fastener, lead or distortion of board. A minimum lead overlap of one inch is required at all joints and corners. Extend lead overhang at least one inch into all frames or openings. Sheet lead over 1/16" thick should have a minimum 2" overhang. Fastened to the wooden or metal studs, using proper drywall screws of the correct length. We suggest you use a minimum of 40 screws per 48" x 84" sheet. Spacing the screws at a maximum of 8" on centre at the edges and a maximum of 12" on centre at the intermediate studs. Screw drywall screws in deeper that normal into wall covering material slightly deeper than the thickness of the lead tab/disk or buttons been used. For drywall/Gypsum board or lath you may create a dimple over the screw head with a swing of your hammer head or other round ended tool to make a 1" diameter impression. Finish by gluing with a construction adhesive the lead buttons usually a minimum of a 7/8" disk over each screw head. After glue has dried out fill in and feather out with wood filler or plaster compound as needed to completely cover the screws and the protection disk devices.
MarShield™ recommends the use of drywall screws in all situations wherever possible. If using lead headed nails (on wood studs only), then ensure that you drive them to the proper depth and cover with drywall compound.
INSTALLATION GUIDELINES FOR LEAD LINING IN FLOORS
In certain situations, the floor and/or ceiling of your room may require radiation shielding. MarShield™ recommends whenever possible laying the sheet lead in the floor before the finished floor is poured. All joints should have a minimum of one inch overlap if multiple pieces are to be used. Overlap at each joint between pieces or apply 2" wide lead strip batten at each joint and glue in place. If multiple layers are to be used, stagger all joints between layers. Ensure your sheet lead selection allows for safe & easy handling at the site and be sure to verify floor-loading limits are adequate with the architect. The Sheet Lead should extend up each wall a minimum of two inches. Additional concrete can be applied over the lead finishing.
If laying sheet lead directly over existing concrete floor then coat fully cured concrete with a sealant like varnish to prevent chemical interaction between the concrete and lead and let the sealant or varnish fully dry. Ensure the lead is free of bumps, air pockets or obstructions and lies completely flat. It is recommended before securing lead to floor that a small sample area be done first to ensure adhesion with the varnish or sealant coating. Use a construction adhesive on hard to secure spots or areas. Press or roll the sheet lead completely flat on the floor.
Prior to laying carpeting, or tile covering we recommend applying an underlay sub floor consisting of a 1/4" or heavier approved plywood or other firm solid material over the Sheet Lead. Fastened down the material with a good quality construction adhesive. Performing this extra step will help spread the floor loading out over a wider area eliminating point loading that could deform the sheet lead below. Alternatively floor anchor bolts countersunk can be used if lead buttons are used over each anchor point.
The lead protection may be obtained in two ways. If possible, it is simplest to lay sheet Lead on top of the floor slab above, allowing it to extend out at least 8" in every direction beyond the lead walls below it.
For health and safety reasons it is recommend there be no exposed lead after your installation is completed. Disposal of all scrap lead must be handled in a proper environmentally & responsible manner. Check with your local by-laws for the proper way of disposing of the remaining scrap lead material. Installation should comply with requirements of local, regulatory agencies and standards specified.
The following information provided should only be used as a general guideline. MarShield™ makes no guarantees or warranties to its accuracies. Most states or provinces have their own local by-laws, provincial, state or federal guidelines on installation & construction practices, radiation protection and proper materials to be used. Marshield will remain harmless in recommending the following guidelines and strongly suggest that you consult with your local authorities and/or by-laws before you begin your construction project.
Our associate company, Overwatch Inc., recommends that after the installation of lead sheet radiation protection and prior to drywall application the walls, doors and windows should be inspected for envelope integrity. Once this inspection has proven to be acceptable, then drywalling can proceed. After the room has been drywalled, and prior to any equipment installation, the lead envelope can then be tested through use of nuclear sources and highly sensitive radiation detection equipment. Always ensure that your contractors are conversant with the local regulations and requirements for both lead handling and installation.
Federal Specification QQ-L-201F Chemical Analysis
DIAGNOSTIC RADIATION SHIELDING CONSIDERATIONS
All Lead Radiation Shielding requirements should be calculated and determined by a certified professional radiation health physicist based on the following information.
The end user must determine the output of the X-Ray machine. (KvP). Usually, the higher the output of the machine, the higher the lead shielding requirement.
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