PSI - Issue 77

Alexander Čaja et al. / Procedia Structural Integrity 77 (2026) 177 – 182 Author name / Structural Integrity Procedia 00 (2026) 000 – 000

180

4

A0_2 A0_3 A0_4 A0_5

0,175

2235 2555 2874 3194

0,2

0,225

0,25

The measured concentration values for particles with sizes ranging from 0.5 ηm, 1.0 ηm and 5.0 ηm can be seen in Fig. 2.

6000

5000

4000

0,5η m 1,0η m 5,0η m

3000

2000

1000

0 Particle concentration [m-3]

A0_1

A0_2

A0_3

A0_4

A0_5

Variant

Fig. 2. Average particle concentration on the operating table for individual variants.

When measuring thermal comfort in a room (heat-humidity balance), the results were evaluated using the PMV and PPD indices. The PMV index evaluates the environment on a scale from -3 to +3, where -3 is a very cold environment, 0 is a neutral and comfortable environment, and +3 is a very hot environment. In practice, the PPD index has proven to be more advantageous, expressing the expected number of people dissatisfied with the indoor microclimate. For a PMV index of 0, the PPD index value is 5%. For PMV values of -3 and +3, the PPD index is 100%. For recording and evaluating objectively measurable quantities, we used the ComfortSense – Dantec Dynamics device, which evaluates thermal comfort according to the EN 13 182, ISO 7726 and ISO 7730 standards.

Fig. 3. Comparison of PPD indices for variants A0_1 to A0_5.