Question 1

Should I choose an electric or an air-operated vacuum?

Accepted Answer

It usually comes down to two things: your area classification and whether you have adequate compressed air at the point of use. An air-operated unit is driven by compressed air through a venturi, so there is no electric motor, no switch and no cord in the recovery unit at all — which removes the electrical ignition question from the drive entirely and suits long continuous running. Electric units suit facilities without sufficient plant air. Both are built with the same conductive, grounded and bonded recovery path, because the dust carries static regardless of what drives the machine. Air units are louder, which is worth planning for in occupied areas.

Question 2

What is the difference between HEPA and ULPA filtration?

Accepted Answer

They are tested at different particle sizes and efficiencies. Standard HEPA is tested to a minimum of 99.97% efficiency at 0.3 micrometres; PrestiVac units are rated at 99.99% absolute, and factory H14 grades reach 99.995%. ULPA extends further, to 99.9995% at 0.12 micrometres. Which you need follows the requirement — the room classification, the exposure limit, or the sanitation standard — rather than a preference for the larger number. Ask what a filter is tested to rather than what it is called.

Question 3

Do you supply dust collectors?

Accepted Answer

No. We manufacture industrial vacuums — explosion-proof, HEPA, air-operated, wet and dry, central systems and custom-built units. A dust collector is a different machine: high air volume at low suction, capturing dust at the source through fixed ducting. A vacuum is lower volume at high suction, removing what has already settled. Most dust programmes need both, and we would rather point you to a collection-system specialist for that half than sell you the wrong equipment.

Question 4

Which of your vacuums are certified, and for what?

Accepted Answer

Our listing is CSA Certificate 70122393, assessed against UL 1203 (5th Edition). It carries two scopes, and they are not interchangeable. The EX1 HEPA drum-type line is covered for Class I, Gp. D; Class II, Gps. E, F and G; Temp. Code T3C. The EV EX HEPA line is covered for Class II, Div. 2, Gps. F and G only — no Class I, Division 2 rather than Division 1, and no Group E, which is the conductive metal-dust group. Commercial indoor use only. Each model page states which scope applies. The air-operated AVX line holds no NRTL certificate at all. We do not claim ATEX or intrinsic-safety approvals.

Question 5

Does your UL 1203 listing cover Class I Groups A, B and C?

Accepted Answer

No. Class I is Group D only — propane, methane and most common hydrocarbons and industrial solvents. Groups A, B and C cover acetylene, hydrogen and ethylene and are not within our listing. Note also that Class I coverage applies to the EX1 HEPA line only; the EV EX HEPA line has no Class I coverage at all, and is limited to Class II, Division 2, Groups F and G.

Question 6

Which line is certified for metal dust?

Accepted Answer

The EX1 HEPA line. Its scope includes Class II, Groups E, F and G, and Group E is the conductive metal-dust group. The EV EX HEPA line is covered for Groups F and G only, so it does not carry Group E coverage — which matters directly in metalworking, aerospace, foundry and battery applications where the dust is frequently Group E. If you are specifying for aluminium, titanium, magnesium or other metal dust, ask us to confirm the line and scope against your area classification before ordering.

Question 7

Which line can be used in a Division 1 area?

Accepted Answer

That depends on the line and on your area classification. The EX1 HEPA line is listed under explosion-proof and dust-ignition-proof enclosure standards. The EV EX HEPA line is listed as nonincendive equipment for Class II, Division 2 — it is not a Division 1 listing. Because Division 1 means the hazardous atmosphere is expected in normal operation, this distinction is not a technicality. Confirm the classification with your engineer and let us match the line to it.

Question 8

Can I use my own hoses and tools with a certified vacuum?

Accepted Answer

Not while keeping the unit in its certified configuration. The listing covers the vacuum together with PrestiVac-supplied hoses and tools, and static-dissipating hose and filters are required. Fitting a hose from general stores or a tool borrowed from another machine takes the unit outside the scope of its listing without anything visibly changing — which is why this tends to happen in service rather than at purchase.

Question 9

Why are the air-operated units not UL 1203 certified?

Accepted Answer

Because UL 1203 is a standard for explosion-proof and dust-ignition-proof electrical equipment, and the AVX line has no electrical components anywhere on the unit. It is a question of scope rather than a shortfall: enclosing an electrical ignition source and removing it entirely are two routes to the same objective, and a standard written for the first does not apply to the second.

Question 10

How must a certified vacuum be grounded?

Accepted Answer

Grounded and bonded in accordance with the National Electrical Code, Article 250. Static-dissipating hose and filters are part of the required configuration. The practical point is that the path has to be continuous from the tool through the hose to the container — a grounded machine with a non-conductive hose attached leaves the charge generated in the hose with nowhere to go, and the machine will keep working normally without anyone noticing.

Question 11

Can one vacuum handle several different materials?

Accepted Answer

Sometimes, but it is worth checking rather than assuming. The constraints are the most demanding material in the mix, the classification of every area the unit will enter, and whether any of the materials should be kept separate. Reactive metal fines should not be combined with other debris or with coolant, and regulated toxic materials such as lead, cadmium and beryllium call for dedicated equipment that never leaves the regulated area. A unit that also cleans the loading dock has no business in a cleanroom.

Question 12

How often should we vacuum a dust area?

Accepted Answer

That comes out of your Dust Hazard Analysis rather than a general rule, because it depends on generation rate, the surfaces involved and the material. What a good programme looks like is specific: a map of which surfaces actually accumulate — including high steel, ledges, duct tops and equipment housings — an interval assigned to each, a defined method, and a record that the pass happened. Cleaning on appearance is the pattern to move away from, because the accumulations that matter most are usually the ones nobody can see from the floor.

Question 13

Why can't we use compressed air to blow down dust?

Accepted Answer

Because it deliberately creates the condition a dust programme exists to prevent. A dust deflagration needs the dust dispersed into a cloud, and blowdown does exactly that — often in an area that already has confinement and ignition sources. It also relocates material rather than removing it, so the same dust settles somewhere else in the building, frequently somewhere less accessible. Vacuum recovery with retained filtration takes the material out instead.

Question 14

What is immersion separation, and when is it needed?

Accepted Answer

It is an approach where recovered material is drawn into a liquid medium rather than collected dry, so reactive fines stay wetted instead of accumulating in a container where heat can build. It comes up with reactive metal dusts — aluminium, magnesium, titanium and zirconium in particular — where dry accumulation of fines is the failure mode you most want to design out. Whether it is appropriate is a material-specific decision, not a default, and it should follow from your assessment of the dust rather than from a product preference.

Question 15

Do you build custom systems?

Accepted Answer

Yes — custom-built systems are part of the range, and with more than 200 versions built over the years most requirements have a precedent. The useful thing to bring is constraints rather than a specification: the material, the area classification, the duty cycle, the footprint available, and how recovered material needs to leave the building. Those five determine what can be built, and asking early about the certification documents your compliance process will require means the build produces them.

Question 16

Is an anti-static vacuum the same as an ESD-safe vacuum?

Accepted Answer

No, though the physics overlaps. Anti-static construction in dust handling exists to stop a static discharge igniting combustible dust — the goal is area safety. ESD-safe equipment in electronics exists to stop electrostatic discharge damaging sensitive components — the goal is protecting product. Both rely on controlled conductivity and a path to ground, but they are specified against different requirements. Battery and semiconductor operations frequently need both, and should say so explicitly rather than assuming one covers the other.

Question 17

What makes a vacuum explosion proof?

Accepted Answer

Every component in the recovery path is engineered so it cannot become an ignition source: conductive, grounded and bonded construction from hose tip to chassis, non-sparking contact materials, filtration that keeps fine dust away from the power unit, and a drive suited to the environment — dust-ignition-protected electrics where permitted, or fully air-operated units with no electrical components at all.

Question 18

Why can't I use a regular shop vacuum?

Accepted Answer

A standard vacuum concentrates the hazard: its motor sparks by design, its plastic hose generates static charge exactly where dust concentration is highest, and its exhaust re-suspends the finest particles back into the air. With combustible dust, that combines fuel, dispersion and ignition source in one tool.

Question 19

Do I need an explosion-proof vacuum?

Accepted Answer

If the dust in your facility is combustible — and most fine organic powders and metal fines are — housekeeping equipment must be engineered for it. The trigger is usually a Dust Hazard Analysis identifying combustible dust, or a classified area rating that governs every piece of equipment used there. When in doubt, have the material tested and speak with an engineer.

Question 20

What is combustible dust and why is it dangerous?

Accepted Answer

Fine particles that can ignite and burn rapidly when suspended in air — and explode when confined. Flour, sugar, grain, wood, most plastics and nearly all metal fines qualify. Settled dust is the fuel for devastating secondary explosions: a layer as thin as 1/32 of an inch over a small fraction of a room can constitute a hazard.

Question 21

Can combustible dust ignite inside a vacuum?

Accepted Answer

Inside unrated equipment, yes — sparking motors, static discharge and hot surfaces are all present where dust concentration peaks. Engineered systems remove those ignition sources: grounded conductive paths control static, power units are protected or air-operated, and for reactive metal fines, immersion separation collects the material directly into a liquid bath.

Question 22

What standards apply to combustible dust housekeeping?

Accepted Answer

NFPA 652 sets the fundamentals, including the Dust Hazard Analysis requirement; NFPA 654 covers combustible particulate processing, NFPA 484 covers metals, with NFPA 61 and 664 for food and wood facilities — all consolidating into NFPA 660. OSHA enforces housekeeping under its Combustible Dust National Emphasis Program. Your DHA and local authority govern what applies to your site.

Question 23

What is a Class II Division 1 area?

Accepted Answer

A North American electrical-area classification where combustible dust is present in the air under normal operating conditions (Division 1) or only under abnormal conditions (Division 2). Equipment used in these areas must be suitable for the classification — which is why fully air-operated vacuums, with no electrical components, are a common choice there.

Question 24

What is the difference between ATEX and IECEx?

Accepted Answer

ATEX is the European Union's legal framework for equipment used in potentially explosive atmospheres; IECEx is the international certification scheme built on the same IEC standards. Both use comparable zone concepts for dust (Zones 20, 21, 22). Which applies depends on where the equipment operates — North American sites typically follow the NEC class/division system instead.

Question 25

Is HEPA filtration required for combustible dust?

Accepted Answer

Not universally mandated — but practically essential for fine dust. HEPA at 99.99% efficiency keeps captured fines captured instead of exhausting them back into the plant air, which matters for combustible loading, operator exposure and product hygiene alike. For potent or toxic powders, filtration level is usually driven by exposure limits rather than combustibility.

Question 26

How do I choose the right industrial vacuum?

Accepted Answer

Start from the material: is it combustible, toxic, wet or abrasive? Then the environment: is the area classified? Then the duty: how much, how often, over what distances? Those answers determine construction, filtration, power source and whether a portable unit or a central system fits. Our solution finder walks through exactly these questions.

Question 27

What is a central vacuum system?

Accepted Answer

A fixed installation: a remote power unit and separator connected to inlet drops throughout the facility through engineered piping. Operators clean at each drop without moving equipment, and collected material consolidates at a single discharge point. Central systems suit facilities with many cleaning points or continuous housekeeping demand.

Question 28

Can I vacuum aluminum dust safely?

Accepted Answer

Yes — with equipment engineered for it. Fine aluminum is among the most severe combustible metal dusts, governed by NFPA 484. Safe recovery means grounded, bonded, explosion-proof construction, and for fine or reactive fractions, immersion separation that collects the material directly into a liquid bath. In classified areas, air-operated units remove electrical ignition sources entirely.

Question 29

What's the right way to clean CNC machines and enclosures?

Accepted Answer

Vacuum recovery at the machine — never compressed-air blowdown, which turns settled chips and fines into an airborne cloud. A wet/dry industrial unit handles chips, fines and coolant together; where the material is a combustible metal, the vacuum must be explosion-proof and grounded, with immersion options for fine fractions.

Question 30

Can one vacuum handle both liquids and dry dust?

Accepted Answer

Only if it's designed for it. Wet & dry systems are configured for coolant, wash-down water and slurry as readily as dry material — and where the dry fraction is combustible, the unit needs explosion-proof wet recovery configuration. Putting liquids into a dry-only vacuum ruins filtration and can create hazards of its own.

Question 31

How often should filters be replaced?

Accepted Answer

By condition, not just calendar: rising pressure drop and falling suction are the practical signals, with frequency driven by duty cycle and material. With combustible or hazardous dust, filter service is part of the housekeeping program itself — captured material and spent filters are handled and disposed of in sealed containers.

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