Proper Handling and Care of Calmetrics Foil Standards
Thank you for your purchase of Calmetrics foil standards. Foil standards allow you to place the foil on any substrate material to emulate measurements of a metal layer on a substrate when using XRF. Calmetrics foils are designed for non-contact XRF instruments only. Foil standards are potentially very fragile and must be handled with care. The following guidance is offered to extend the useful life of your foils:
- Always store the foils, when not in use, in the membrane boxes provided. The boxes containing the foil standards should be stored in a cool, dry environment
- (< 25º C and < 40% relative humidity). If the foils are mounted in fixtures as sets,
- provided by Calmetrics, always leave the foils in these fixtures and store them in the
- boxes provided.
- When you need to use the foils stored in membrane boxes, slowly remove the box cover to allow air pressure inside the box to reach equilibrium with ambient air pressure.
- If the foil is wrapped in paper, remove it carefully to use the foil. When you want to store the foil in the box, cover it again in the paper provided. This will help to avoid any adhesion that may develop between the foil and the support membrane in the box. Some foils, particularly copper and silver foils will be covered with anti-tarnish paper. Please replace this paper back onto the foil surfaces when storing the foil to minimize oxidation. Anti-tarnish paper should be placed with the plain, non-printed side against the exposed foil surfaces. NOTE: Oxidation of metal foils does not invalidate the certified thickness and composition values. Oxidized surfaces do not have any significant effect on XRF measurements. You may still use your foil(s) if an oxidation layer develops. The anti-tarnish paper is provided to attempt to maintain an attractive appearance and delay the development of severe oxidation which will compromise the integrity of your foil, leading to eventual, spontaneous damage.
- Never touch the foil in the center opening. Always handle the foil by grasping the stainless steel foil frame by the edges.
- Never try to clean a foil surface.
- Avoid placing the foil on any surfaces that place pressure on the foil or have sharp edges, burrs or rough areas that may puncture the foil. Also avoid sliding foils on surfaces. Place foils gently onto the substrate you want to measure the foil on. Large, flat and smooth metal samples make the best base material on which to place foils.
- Dropping foils will often cause damage and break foils. It is recommended when transferring the foil from the box to the instrument, that you use your second hand placed under the hand holding the foil to help prevent it from dropping accidentally.
- Removal of foils from fixtures (e.g., autocal racks) provided by Calmetrics for sets of foils, in order to change substrate material, should be done carefully. Please refer to separate instructions for this procedure.
- If you suspect or know a foil has been damaged, please request a Return Authorization Number from Calmetrics and return it to us for evaluation, at your earliest convenience.
- Many foils are coated with a thin organic protective layer on the backside or even both sides. This layer normally will not affect XRF measurements and will provide added support for the foil and afford some anti-corrosion protection. In a few exceptional cases, this coating cannot be applied as it will significantly interfere with XRF measurements (e.g., Al foils, Ni-P foils used for % P measurement and thin Ag, Pd, or Sn foils where L-line analysis is used for measurement). Handle such foils with extra care as these may be especially fragile and vulnerable to damage.
- Do not attempt to remove the label from the foil standard. This can flex the foil frame and stress the foil to the breaking point.