RMD LPA-1 XRF Spectrum Analyzer
for Conducting Lead-Based Paint Inspections

Frequently Asked Questions

How does XRF work? 

• The surface to be measured is irradiated with gamma rays that excite the emission of K shell x-rays.  The gamma ray source in the LPA-1 is an isotope of cobalt, Co57.  The x-rays are then collected by a solid state radiation detector within the analyzer.  The lead concentration is then computed and displayed in mg/cm2. 
• The LPA-1 method of measurement is based on the spectrometric analysis of lead K-shell x-ray fluorescence in a controlled depth of paint.  K-shell energy can easily go through the paint without being affected by different thickness and composition of various layers of paint that can cause false readings.  Controlled depth used in the design of the LPA-1 XRF Lead Paint Analyzer restricts the penetration of the energetic K-shell x-rays into the substrate.  The system cannot be misled by the presence of lead pipes or other objects located deep in a wall.

What makes the LPA-1 so fast?

• The half life for CO57 is approximately nine months (272 days).  This period is fixed by nature.  The source will decay at the same rate whether the instrument is used once or a million times.  It is not necessary, however, to change the source after one half life.  The source in the LPA-1 can be used well beyond nine months.  In fact the instrument’s intelligence will automatically adjust for the age of the source in Quick Mode or when using the Time Corrected Mode during calibration checks.  RMD recommends changing the source every 12-15 months.  After fifteen months it becomes difficult to service the instrument properly. 

• The LPA-1 Analyzer contains a maximum of 12 mCi (millicurie) of Cobalt 57 (Co57) radioactive material sealed, and housed in a tungsten shield inside the instrument.  The source can only be exposed when the system is in contact with a surface.  The low activity of the source and the shield, along with proper operation results in no radiation hazard to the operator.  The radiation dose rate at the operators hand is approximately 0.3 mRem/hr (Millirem per hour) with the shutter open or closed.  This is substantially below the permissible dose rate.  The LPA-1 Analyzer has been through the Device Safety Evaluation Review and is a nationally registered device. 

• The LPA-1 has been issued a Performance Characteristic Sheet (PCS).  Call us to obtain a copy. It is also available for downloading from our website, the HUD website or by calling the HUD clearing house at 1-800-424-LEAD. 

• In order for RMD to deliver any LPA-1 three items must be completed.  First, the user must receive a license or registration from the local state agency. Some states accept a general license. (Call for the LPA-1 Specification & Licensing Requirements for instructions).  A copy of the device specific license or general license registration approval may be mailed or faxed to RMD prior to shipment.  Second, the user must complete a factory authorized training course.  The training, provided by RMD, can be completed in one day and is included in the purchase price.  Finally, payment must be arranged.  Accepted methods include, a certified or bank check, a signed and approved lease agreement, or an institution or government purchase order. 

• While customers are always welcome to train and tour the facility in Watertown, MA, RMD holds regular training sessions around the country.  Call for exact location and dates. 

• For those who wish to finance their purchase, RMD works through several leasing companies to allow customers to spread out payment in convenient monthly installments.  All leases allow the user to buy the instrument at the end for a nominal charge of $1. 

Will the software run on my computer?

• RMD recommends an IBM compatible Pentium 1 or higher with 64 megs of RAM and one unused serial port to run the software. Software is compatible with Windows® 95, 98, ME, 2000 and XP and mobile CE portable PC platforms. Software updates are available at no charge to customers. A total of 4,000 readings can be stored in the LPA-1. Individual file sizes should be kept at or below 1,000 readings per job.