General Knowledge Flashcards
Testing combinations are defined as a combination of:
Room equivalent, component type, and substrate
An XRF Performance Characteristic Sheet defines:
Acceptable operating specifications & procedures for each XRF unit, ranges where XRF results are positive, negative, or inconclusive.
Paint chip samples should be analyzed by a lab recognized under:
National Lead Laboratory Accreditation Program NLLAP
What is the size of a paint chip sample
4 square inches`
A Lead-Based Paint Inspection determines:
Whether lead-based paint is present in house, dwelling unit, residential building or housing development, and if present, which building components contain lead-based paint.
HUD/EPA definition of Lead-Based Paint:
1.0mg/cm2 or .5% by weight
(Defined in Title X of the 1992 Housing & Community Development Act)
Equivalent units to .5%=5000 micrograms/g or 5000 mg/kg or 5000pmm
XRF instruments must be calibrated
3 times at the beginning of the inspection AND at every 4 hours or at the end of the inspection (whichever comes first)
Inconclusive results (in single family dwellings) must….
be confirmed in lab unless client wishes to assume that all inconclusive results are positive.
Paint chip samples should include
All layers of paint, including the bottom layer
Surface area of sampled area must be recorded.
Inspection report should include the following:
Who performed inspection Date Inspector's cert number All XRF readings Classification of all surfaces into pos or neg Specific info on XRF & lab methodologies Housing unit and sampling location identifiers Results of lab analysis Additional info
Can the lead-based paint inspection protocol be used in units where children with elevated blood lead levels are residing?
NO - Must follow protocol from Chapter 16
Risk Assessment
Determines the presence of lead-based paint hazards
True or False: A risk assessment requires less paint samples
True: For a risk assessment, only lead in deteriorated paint (dust and soil) is measured. Inspections measure lead in both deteriorated and intact paint, involving more surfaces.
Risk Assessments also note condition of paint films, inspections may not.
Can mobile labs be used?
Yes, if recognized under NLLAP
Are chemical test kits acceptable to use for a lead-based paint inspection
NO
The mass of lead in a given surface area on a substrate measured in mg/cm2
Lead Loading
If the component has layers of different substrates, which should be used?
The substrate immediately adjacent to the painted surface.
For similar building component types with identical substrates, testing of the component type can discontinue when:
All are found to contain lead-based paint in the first five interior room equivalents. (if and only if the client agrees to this)
Where is an XRF test required?
For at least one location per testing combination, except for exterior and interior walls, where four readings should be taken (one on each wall),
When a room equivalent has more than 4 walls, the test results must be:
Averaged and rounded to the same number of decimal places as the XRF instrument displays. Classify remaining walls (w/ same painting history) based on the rounded avg.
The best location to sample paint
Where paint is the thickest. Avoid areas where paint has been scraped off, or areas over pipes, electrical surfaces, nails, etc.
Half life of Cobalt-57
270 days
Half life of Cadmium-109
464 days
How are calibration check readings recorded?
By averaging the 3 calibration check readings, rounded to the same number of decimal places as the XRF instrument displays.
The correction value, used for substrate correction when XRF results are corrected for substrate bias is:
An average of 6 XRF readings, with 3 taken from each of two test locations that have been scraped visually clean of their paint coating.
Positive XRF Reading
At or above HUD/EPA standard of 1.0mg/cm2
Negative XRF Reading
Indicates that lead is not present at or above the HUD/EPA standard
Inconclusive XRF Reading
XRF cannot determine with reasonable certainty whether lead is present. These results must be confirmed by lab analysis unless client wishes to consider them positive.
Any group of units that are similar in construction from unit to unit, with:
- 21 or more units if any were built before 1960 or are unknown age OR
- 10 or more units, if they were built from 1960-1977
Multifamily Housing
Developments with fewer units should be treated as a series of single-family housing units.
How are housing units selected for testing in multifamily housing?
Buildings in development with common construction are identified. Then are randomly selected using a chart or calculator.
What is the equation for random selection of units?
Housing unit # = Random # (between 0-1) x Total # of units.
A duplicate unit selection should be….
Entered as a DUP to show that the selection was a duplicate and then discarded.
Types of laboratory analysis
Atomic Absorption Spectroscopy (AAS)
Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES)
Anodic Stripping Voltammetry (ASV)
Potentiometric Stripping Voltammetry (PSV)
Equation used to report results in micrograms per gram
microgram/g = weight of lead from sample in microgram/g (divided by) subsample weight in grams
Equation used to report in milligrams per square centimeter
mg/cm2= weight of lead from sample in mg x total sample weight in grams (divided by) subsample weight (in grams) (all divided by) sample area (in cm2)