Db represents a new national standard in explosion-proof markings and protection levels, specifically designed for devices in dust environments applicable to Zones 21 and 22.
| III | C | T 135°C | Db | IP65 |
|---|---|---|---|---|
| III Surface dust | T1 450°C | Ma | IP65 | |
| T2 300°C | Mb | |||
| T3 200°C | ||||
| A Flammable flying flocs | Da | |||
| T4 135°C | ||||
| Db | ||||
| B Non conductive dust | T2 100°C | Dc | ||
| C Conductive dust | T6 85°C |
An example is DIP A21 TA T6 Db DIP, indicating a device for dust environments; if labeled as Ex, it indicates suitability for gas environments.
