Based on the scenario of your negative pressure weighing chamber, I have clearly listed the differences and reasons for the replacement cycles of different types of high-efficiency filters, while also differentiating by structure, material, and application scenario, to facilitate your direct use in equipment management:
1. Classified by filtration efficiency grade
| Type | Applicable scenarios | Regular replacement cycle | Reasons for cycle differences |
| H13 High-efficiency Filter | Negative pressure weighing room, normal clean area air supply | 12 ~ 24 months | The filter paper has an appropriate pore size and a moderate dust holding capacity, and is a mainstream configuration for the weighing chamber. |
| H14 Ultra-High Efficiency Filter | Highly active, sterile, and highly precise weighing | 10 ~ 18 months | Higher filtration accuracy, denser filter paper, faster increase in wind resistance, prone to clogging |
II. Classification by Filter Material
Conventional Glass Fiber High-Efficiency Filter
Period: 12-24 months
Features: Large dust holding capacity, suitable for dry dust environments, high cost performance
PTFE Coated High-Efficiency Filter
Period: 8-12 months
Features: Dust adheres only to the surface, not easily penetrable, but the surface is prone to accumulate dust and block, and the resistance rises rapidly; resistant to acid and alkali, resistant to humidity, suitable for frequent disinfection scenarios
High Humidity/Tolerance to Chemicals Filter Material
Period: 6-12 months
Features: Strong environmental corrosiveness, filter material prone to aging, cycle significantly shortened
III. Classification by Structural Form
High-Efficiency Filter with Partition
Aluminum foil partition support, large pleat spacing, large dust holding space
Replacement period: 18-24 months, relatively longer lifespan
High-Efficiency Filter without Partition
Hot melt adhesive separation, dense pleats, large filtration area but prone to dust accumulation
Replacement period: 12-18 months, currently the most commonly used in weighing rooms
IV. Classification by Installation Position & Operating Conditions (Key)
Negative Pressure Weighing Room Supply Air High-Efficiency
Common raw materials and auxiliary materials: 12 months or so
Highly active, toxic powder, Chinese herbal fine powder: 6-12 months
Weighing Room Exhaust High-Efficiency
Direct contact with dust, extremely high pollution load
Replacement period: 3-6 months, much shorter than the supply air end
V. Important Reminder
All of the above are reference periods and cannot be used as the sole basis for replacement
When the final resistance of the filter reaches twice the initial resistance, regardless of the usage duration, it must be replaced
If PAO leak detection shows leakage or the wind speed does not meet the standard, it must be replaced immediately
If the initial and intermediate efficiency filters at the front are well maintained, it can effectively extend the lifespan of the high-efficiency filter
