Technical Standard Comparisons

A handy tool to compare the ATTMA standard to ISO 9972:2012 technical standard.

 ATTMA TSL1: 2021ISO 9972:2015TM23:2022
Intended Building TypeAll BuildingsSingle-zoned buildings or multi-zone buildings treated as single-zone buildingsSingle-zoned buildings or multi-zone buildings treated as single-zone buildings
Recommended Test Conditions<6m/s windWind at Ground <3m/s
Wind at Station <6m/s
Wind <3 on Beaufort Scale
∆T x Height  < 250 mK
Wind at Ground <3m/s
Wind at Station <6m/s
Wind <3 on Beaufort Scale
∆T x Height  < 250 mK
Zero Flow Pressure Measurement30 second averages;
before and after flow measurements
Over 30 seconds at least 10 separate readings; before and after flow measurementsOver 30 seconds at least 10 separate readings; before and after flow measurements
Maximum Zero-Flow Pressure (all readings)< +/- 5 Pascals< +/- 5 Pascals< +/- 5 Pascals
Maximum Zero-Flow Pressure (all-negative readings)< -5 Pascals< -5 Pascals< -5 Pascals
Maximum Zero-Flow Pressure (all-positive readings)< +5 Pascals< +5 Pascals< +5 Pascals
Lowest Minimum Test Pressure10 Pa;
or 5 times the zero-flow pressure
10 Pa (+/- 3Pa);
or 5 times the zero-flow pressure
10 Pa;
or 5 times the zero-flow pressure
Lowest Maximum Test Pressure50 Pa50 Pa;
25 Pa is an acceptable deviation
50 Pa
Minimum spread of test pressures from low to high30 Pa (recommended)n/a30 Pa
Example Range of Test Pressure Differences+/- 10 to +/- 90 Pan/an/a
Number of Test Points & Duration7 (stable for 30s per reading)77
Maximum Space between Data Points10 Paapprox. 10 Pa10 Pa
Preferred Test DirectionBothBothBoth
Acceptable Test DirectionEither or BothEither or BothEither or Both (Preferred)
Acceptable Range: n0.50 ≤ n ≤ 1.00
0.50 ≤ n ≤ 1.00
0.50 ≤ n ≤ 1.00
Acceptable Range: r2r² >= 0.98
r² >= 0.98
r² >= 0.98
Uniform Building PressureIndicates that a check of single-zone conditions should be performed to ensure that the interior pressure differs by no greater than 10% of the measured test pressure from the geometric centre to the top and bottom of the building when it has more than six storey or is greater than 18m in height with 3 or more storeyIn tall buildings it is good practice to measure the pressure difference at the top floor level of the building as well as the bottomFor large buildings (greater than three stories or 10 m in height) measured at the lowest and highest floor levels
Reporting Metric(s)Air Permeability Preferred
m3.h-1.m-2 @ 50 Pa
Air Permeability Preferred
m3.h-1.m-2 @ 50 Pa
Air Permeability Preferred
m3.h-1.m-2 @ 50 Pa
Equipment Precision+/- 7% airflow+/- 7% airflow+/- 7% airflow