NEBB BET CP flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

ASTM E779

Standard test method for determining air leakage rate by fan pressurization. It produces a multipoint pressure-flow series used to calculate the flow coefficient, flow exponent, and normalized leakage.

ASTM E1827

Standard test methods for determining airtightness of buildings using an orifice blower door. It provides a simplified procedure for whole-building air leakage measurement and reporting.

ASTM E783

Field test method for measuring air leakage of installed exterior windows, doors, and skylights. A chamber applies pressure across the specimen and flow is measured at specified pressures.

ASTM E1105

Field test method for water penetration of installed exterior windows, doors, and skylights. A calibrated spray rack applies water while a chamber maintains the specified pressure difference for the test duration.

ASTM E283

Laboratory test method for determining the rate of air leakage through exterior windows, doors, and skylights. It measures leakage at a specified pressure difference across the specimen.

ASTM E1186

Standard practices for air leakage site detection in building envelopes and air barrier systems. It covers qualitative methods such as smoke tracer, infrared thermography, and pressure-difference testing.

ASTM E2357

Standard test method for determining air leakage of air barrier assemblies. A wall assembly is subjected to specified pressure and the leakage is measured to evaluate joints and details.

ASTM E2178

Standard test method for determining air permeance of air barrier materials. Results are typically reported in liters per second per square meter at a reference pressure of 75 Pa.

Flow exponent n

The exponent in the leakage equation Q = C times pressure difference raised to n. Values near 0.5 indicate orifice flow; values near 0.65 to 0.7 indicate long crack flow.

ACH50

Air changes per hour at 50 Pa pressure difference. It equals the measured flow at 50 Pa multiplied by 60 and divided by the conditioned building volume.

Effective leakage area

The equivalent open area that would produce the measured leakage at a reference pressure. It is calculated from measured flow, air density, reference pressure, and a discharge coefficient.

Reference pressure

The pressure difference at which air leakage is normalized and reported. Common values are 50 Pa for residential programs and 75 Pa for commercial specifications.

Baseline pressure

The indoor-outdoor pressure difference measured before fan operation. It must be subtracted from subsequent readings and should be stable during the measurement period.

Multipoint pressure series

A set of at least five to eight flow measurements at increasing pressure differences, typically from about 15 Pa to 60-75 Pa, used to fit the leakage equation by regression.

Correlation coefficient r-squared

A statistical measure of how well the log-log regression fits the measured pressure-flow data. Values of at least 0.98 to 0.99 indicate a valid multipoint test.

Spray rack rate

The water application rate used in ASTM E1105 field water testing, approximately 5 gallons per hour per square foot, or about 3.4 liters per minute per square meter.

Water test duration

The minimum time water is applied at the specified pressure in ASTM E1105. The standard minimum is 15 minutes, though project specifications may require longer.

AAMA 501.1

A dynamic water penetration test method using cyclic pressure and a calibrated propeller. It differs from ASTM E1105, which uses static pressure and a spray rack.

AAMA 501.2

A qualitative field hose test for water penetration at joints and interfaces. It is a quick check and is not a substitute for the quantitative ASTM E1105 chamber test.

Infrared thermography

A qualitative method for locating air leakage and insulation defects. Reliable results require at least about 10 degrees Celsius indoor-outdoor temperature difference and minimal solar loading.

Smoke tracer method

A qualitative technique that uses smoke to visualize air movement and locate leakage paths. It identifies locations but does not quantify the leakage rate.

Pressure gauge calibration

Verification of a differential pressure transmitter against a reference manometer. Calibration should be within the past 12 months, with zero and span checked before and after testing.

Air density correction

Adjustment of measured flow to a stated reference air density, accounting for temperature and altitude. Results compared to specifications must state the density basis used.

Gross envelope area

The total exterior surface area of walls, roof, and floor measured to outside faces, excluding interior partitions. It is the normalization basis for leakage per unit area.

Conditioned volume

The interior volume of spaces that are heated or cooled. It is used in air change calculations; unconditioned attached spaces are excluded unless the specification states otherwise.

Depressurization test

A blower door test in which indoor pressure is reduced below outdoor pressure, drawing outdoor air inward through leaks. The test direction must be recorded and reported.

Field mockup testing

Testing of a representative assembly before full installation to validate detailing and workmanship. Results inform project acceptance criteria and quality assurance planning.

Air barrier continuity

The requirement that the air barrier be unbroken across the entire envelope, including roof-wall, wall-foundation, and window-wall transitions and all penetrations.

Vapor retarder permeance

A material property measured by ASTM E96, expressing water vapor diffusion rate. It is a separate requirement from air barrier performance and is tested by a different method.

Acceptance criterion

The project-specified performance value that a test result must meet. It must state the test standard, reference pressure, normalization basis, and required value to be enforceable.

Re-test after repair

Verification testing performed after corrective work. It must use the same method, pressure, and duration as the original test to demonstrate compliance with the original criterion.

Test report contents

A compliant report includes the method, specimen description, conditions, equipment and calibration, raw data, calculations, results, conclusions, and a signed identification of the testing agency.

Independent verification

Re-testing by a separate agency when results are disputed. Data reduction and assumptions are compared line by line to resolve the disagreement.