What are important characteristics in choosing portable dental Units?

Important considerations for an effective portable dental delivery system include:

Transportability (how easily it can be moved and utilized):
>weight and size characteristics
>ability to transport the equipment (cubic feet needed — will it fit into your vehicle?)
>carrying case and/or dolly system (is there a built-in handle and/or dolly system? If not, can you utilize generic cart systems effectively to move equipment?)
>capacity to selectively take only the dental equipment you need
>ease of moving the assembled equipment
>capability of transporting equipment into various settings (e.g.,  up/down stairs, through narrow doorways)

Durability (likelihood of malfunction because of constantly moving the units):

>protective carrying cases
>protective padding systems for lights and other delicate equipment
>equipment engineered sufficiently to minimize need for frequent repairs
>avoiding need for repairs

Ergonomic characteristics (creation of an efficient working environment):
>favorable relation of portable dental unit functions to weight and size
>dental chair allows variety of positioning options (e.g., height and reclining angle); movable arm rests to allow wheelchair transfers
>adjustability of operator and assistant stools
>convenient location of handpieces, suction, water and air syringe, and rheostat (foot pedal)
>dental light positioning flexibility for illumination
>dental x-ray unit weight, stability and positioning (stationary tripod bases are less effective than a concave base on wheels that facilitates better x-ray head positioning)
>portable delivery system layout matches available room layouts (equipment should be small enough and flexible enough to be used in a variety of spaces)

Delivery system capabilities (capacity for effective dental treatment provision):
>ability to provide a range of dental services(should also allow for 4-handed delivery of care–dentist/hygienist and dental assistant working together on the same patient)
>portable dental unit  provides adequate sustainable pounds per square inch (psi) for high-speed and low-speed handpieces (35-50 psi is recommended for handpiece operation)
>portable dental unit provides adequate sustainable cubic feet per min (cfm) for high-volume and low-volume suction (2.5-5.0 scfm)
using the handpiece and portable dental suction unit at the same time is possible and does not cause a decline in the functional capabilities of either feature
>supports multiple handpieces

>supports an ultrasonic scaler
>supports fiber optic capability for handpieces to improve visualization of the mouth in settings with less ambient light
>supports air turbine, electric, and/or cable handpieces

dental light should be quartz halogen-based and provide adequate foot-candles for illumination (should provide about 1000 ft candles at working distance of 2 ft)
sufficient suction and water bottle capacity–at least 500 ml (larger size will decrease frequency of emptying the waste or refilling the water bottles)there is an adequate air reservoir to provide continuous sustainable power to the handpiece (1-9 liters with larger capacities preferable to minimize the running of the compressor)

Infection control (meeting OSHA’s requirements for cleanliness and asepsis):
>cleaning and disinfection of the unit
>flushing handpiece and waterlines
>ease of removing suction contaminates from the vacuum to the drain and disinfection

Maintenance (how to avoid “downtime”)
> extent and frequency of preventive maintenance activities (e.g., cleaning, flushing, lubrication
ease of performing needed maintenance and minor repairs (e.g., replacing gaskets, filters, hoses, and/or fuses)
on-site repair capabilities
>repair of more complex problems and need to ship components for servicing or repairs
> loaner unit availability from vendor when extensive repairs are needed

Ease of assembly/disassembly (starting and finishing):
>time and effort needed to set-up unit(s)
>time and effort needed to clean and disassemble unit(s)

Noise level (how loud is it and can it be modified):
Dental compressor and vacuum noise–sound levels may range from 40-70 decibels at 3 to 4 feet (if noisy, check on compressor capability to be placed some distance away from the treatment area; oilless compressors are generally louder than non-oilless ones; check other variables such as air reservoir or continuous flow versus an intermittent flow design)
Source:
https://www.oyodental.com/blog/2016/05/25/what-should-take-into-considertation-in-choosing-portable-dental-units/