Table 2.
Differences in FEV1 and PEF values for the National Institute for Occupational Safety and Health HF5 and EasyOne spirometers during a pinch test of the spirette at ½, ⅜, ¼ and ⅛ inches of the spirette's original diameter using waveforms 1 & 19 from the 26 ATS standard flow-time waveforms.
| Diameter of mouthpiece (inches) | ATS Wave Form Number | FEV1 (L)* | PEF (L/sec)† | ||||
|---|---|---|---|---|---|---|---|
| HF5 | Easyone | Difference‡ | HF5 | Easyone | Difference‡ | ||
| .500 or ½” | 1 | 3.52 | 3.53 | 0.01 | 7.87 | 7.87 | 0.00 |
| 19 | 3.19 | 3.17 | 0.02 | 7.40 | 7.45 | 0.05 | |
|
| |||||||
| .375 or ⅜” | 1 | 3.61 | 3.59 | 0.02 | 8.13 | 8.00 | 0.13 |
| 19 | 3.21 | 3.05 | 0.16 | 7.43 | 7.02 | 0.41 | |
|
| |||||||
| .250 or ¼” | 1 | 3.56 | 3.6 | 0.04 | 7.77 | 7.75 | 0.02 |
| 19 | 3.24 | 3.25 | 0.01 | 7.47 | 7.50 | 0.03 | |
|
| |||||||
| .125 or ⅛” | 1 | 2.56 | 2.17 | 0.39 | 6.05 | 4.65 | 1.40 |
| 19 | 2.6 | 2.58 | 0.02 | 5.72 | 7.38 | 1.66 | |
*
FEV1 = forced expiratory volume in one second
†
PEF = peak expiratory flow rate
‡
Difference calculated as EasyOne measurement – HF5 measurement