Frequently Asked Questions (FAQs)

How long does it take a replacement part to be shipped once I have placed the order?
If the part is in stock at our European warehouse in Hamburg, Germany and credit terms have been established, we can usually ship the order within 2-3 days. For palletised shipments there are normally at least two groupage departures per week from Hamburg to most European destinations. For more information, contact us.

Where do I find replacement filters for my MAC 10 unit (FFU)?
We can supply replacement filters for any Envirco MAC 10 Fan Filter Unit. It is important to identify which MAC 10 model and size so that the correct replacement filter is supplied. Each MAC 10 Fan Filter Unit has a unit label on the upper casing and a filter label on the side of the housing.

Do you have an operations manual for my unit?
Yes, we can supply a manual for MAC 10 units that we have manufactured. To identify the correct unit and the corresponding manual, please supply the unit's model number or serial number which is located next to the electrical box.

How can I order replacement parts?
We can supply replacement parts for most units that we have manufactured. To identify the correct unit and the proper parts, please supply the unit's model number or serial number which is located next to the motor/ fan assembly. For more information, contact us.

What is unidirectional / laminar airflow?
Unidirectional or laminar airflow is a controlled airflow in which the entire volume of air within a designated space moves at a uniform velocity in a single direction along parallel flow lines.

How large is a micron?
A micron is equal to one-millionth of a meter. A human hair, for example, is about 75 microns in diameter, while bacteria can range in size from 0.35 - 10 microns. The smallest particle the human eye can see is 50 microns.

What are HEPA and ULPA filters?
The High Efficiency Particulate Air (HEPA) mini-pleat filters that we supply are at least 99.99% efficient in removing particles 0.3 micron and larger (Grade H13 meeting ISO 6 clean room class). HEPA filters utilise spun-hooked glass fibre rolled into a paper-like material. This material is pleated to increase the fibre surface area and bonded, or potted, into a frame. Hot melt is used to hold the pleats far enough apart to allow air to flow between them. Ultra Low Penetration Air (ULPA) filters are at least 99.9995% efficient in removing particles 0.12 micron and larger (Grade U15 meeting ISO 4 & 5 clean room classes). Like HEPA filters, ULPA filters are made of spun-hooked glass fibre rolled into a paper-like material. All our filters are individually auto-scanned to provide a unique efficiency.

Will a HEPA filter capture viruses?
Yes. Studies by Langmuir concluded that the theoretical HEPA filter efficiency was a minimum for particles that are sized 0.3 micron in diameter, with efficiency increasing for particles both larger and smaller than 0.3 micron. Most viruses fall within the 0.01 to 0.5 micron range. Within this range, HEPA filters are at least 99.99% efficient.

How long will a HEPA filter last?
A HEPA filter can last three to five years or more in a standard cleanroom environment. The life of the HEPA also depends on ambient conditions, the pressure drop across the clean room and maintenance of the pre-filters. Since airflow capacity decreases and static pressure increases over time, HEPA filters actually become more efficient as the filter loads. The filter should be changed once it has reached its capacity. For example, if a HEPA unit is set to 0.45 m/sec outlet velocity but is only achieving 0.35 m/sec, then the HEPA filter should be changed. Some manufacturing industries insist on changing filters every two years regardless of their condition.

How often do I need to change the prefilter?
In dirtier environments, the pre-filter may need to be changed as often as every one to three months. Frequency will depend on the ambient conditions. If the MAC 10 Fan Filter Units are operating within a high-grade re-circulating clean room the need to change the pre-filters is much reduced.