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, such as a motor, Envirco can usually ship the order within 3 to 5 days. If the part is required sooner, a modest expedite fee will apply. All parts are shipped from our Sanford, North Carolina, USA location. For more information, contact us.

Where do I find replacement filters for my MAC 10 unit?
Envirco can supply replacement filters for any MAC 10 unit. It is important to identify which MAC 10 model and size so that the correct replacement filter is supplied.

Do you have an operations manual for my unit?
Yes, we can supply operations and maintenance manuals for units that we have manufactured. To identify the correct unit and the corresponding manual, please supply the unit's model number or serial number (generally located next to the motor/blower assembly, beneath the prefilter), and any identifying brand or unit name.

How can I order replacement parts?
Envirco 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 (generally located next to the motor/blower assembly, beneath the prefilter). For more information, contact us.

What is laminar airflow?
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?
High Efficiency Particulate Air (HEPA) filters are 99.99% efficient in removing particles 0.3 micron and larger. HEPA filters utilize spun-hooked glass fiber rolled into a paper-like material. This material is pleated to increase the fiber 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 99.9995% efficient in removing particles 0.12 micron and larger. Like HEPA filters, ULPA filters are made of spun-hooked glass fiber rolled into a paper-like material. Envirco's filters meet the latest IEST Recommended Practices.

Will a HEPA filter capture viruses?
Yes. Studies by Langmulr 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. Life of the HEPA also depends on ambient conditions and maintenance of the prefilters. 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 for 90 ft/min (0.45 m/sec) on the setting, but is only achieving 70 ft/min (0.35 m/sec) on , then the HEPA filter should be changed.

How often do I need to change the prefilter?
In dirtier environments, the prefilter may need to be changed as often as every one to three months. Frequency will depend on ambient conditions.