Controlling and mitigating the airborne dust in healthcare construction is important. But that only represents half of the job. Today the best dust control programs also monitor the performance of the dust removal - by using air particle sensors and differential pressure sensors in areas where the excess dust can become a problem.
What harm can a little dust do?
The presence of dust during the healthcare construction project can have serious consequences. Dust can transport Silica dust and airborne bacteria, such as aspergillus, with a severe health impact. Dust can also cause malfunction of hospital medical equipment, and a very fine dust may increase the risk for explosion and fire. During the renovation and facility expansion projects in hospital wards with operating rooms, ICUs or newborn nurseries, the importance of cleanliness is, of course, always of top concern. It is, therefore, no exaggeration to say that, if not managed and monitored properly during construction, the effects of the dust can be deadly.
Dust in healthcare construction can be expensive
If the dust is let to migrate to clean areas during the construction, it can also have a major impact on project profitability. The unbudgeted project expenses and schedule delays, associated with the extra cleaning effort, tend to be larger if the contractor is responding to complaints only after the completion of the project. Preparing detailed dust mitigation measures during the planning stages is less costly and less disruptive. Measuring the dust mitigation results in real-time during the project will further help to avoid any surprises at the end.
Best-practice planning for hospital construction dust control
There are well-established guidelines for Pre-Construction Risk Assessment (PCRA) programs, during which all hospital departments should discuss risks associated with the construction project – including the impact of airborne dust.
Controlling dust and preventing the unfiltered air from entering the clear areas are the primary goals of dust controls in health care construction. Temporary floor-to-ceiling dust barrier walls or plastic “zip-walls” are used to isolate construction areas from the rest of the building.
After establishing these physical dust barriers, the primary tool for controlling the dust is depressurizing the construction areas to prevent the dust from entering the adjacent spaces. High-efficiency negative air machines and air scrubbers, with HEPA-filters, are placed inside the work area to draw air from clean areas (w/positive pressure) to dirty construction/work areas (w/negative pressure).
With well-thought-out sectioning of depressurized construction areas, the dust control typically functions well, so that the clean areas will stay clean enough for continued operations. But, what if – the depressurizing does not work as planned, or if the pressure difference is not big enough (typically targeting minimum pressure difference of 5 Pascals or 0.002 Inch or w.c.)? What if there are still some unidentified inlets for the dust to enter the clean areas?
In other words, how do we know if the dust control plan is actually working?
Wireless IoT sensors are monitoring dust control performance in real-time
The latest cloud-connected and highly accurate IoT sensors can be a great tool for construction managers. They are easy to install without complex wiring and can send immediate mobile alerts when the jobsite conditions change. This works well also for the dust control program.
The best wireless dust sensors can measure and report several air particle size classes at the same time. For example, one may want to have a separate alert for airborne particles that are size PM5.0 or smaller, as they are the most severe health risk. The larger particles may not be causing health problems but may indicate that dust control is not working, and extra cleaning may be required.
Differential pressure (DP) sensors are installed between the negative and positive pressure spaces. They will send an alert when the pressure difference drops below the desired threshold or can also send a trigger to the ventilation machines for adjusting power automatically as needed.
Traditional methods of monitoring pressure differentials using telltale flags, smoke testing, or local manometers, cannot compete with wireless IoT sensors anymore. When using the smoke testing, you have to be onsite monitoring the smoke. With wireless IOT sensors, you gain peace of mind as the sensors are performing the monitoring for you 24/7. You can forget the whole thing until a mobile alert will trigger your corrective action.
eGate Dust and Differential Pressure sensors provide the highest reliability and accuracy
As an example of state-of-the-art Dust and DP sensors, here are two sensor products manufactured by e-Gate.io. Both products are directly connected to the internet and the cloud platform, by using the global LoraWAN carrier network.
- eGate KOMBI – sensor measures differential pressure (DP), ambient Temp/RH, CO2 and VOC values.
- DP measurement method is using a flow-through sensor to measure the pressure difference between two spaces.
- A thin plastic tube is extended from the sensor connector, over maximum 1 meter (3 ft) length, to the other side of the wall, so that the sensor can monitor the pressure difference of two spaces.
- The PD measurement accuracy is +/-0.2 Pascal (0.0008 Inch w.c) + 4% from reading
- Battery life is up to 5 years with 15min measurement interval
- Works together with the eGate Cloud data platform with mobile phone connection and open API interface
- eGate DUST-13 – sensor measures air particles sizes 0.35…12.4µm, divided in 16 particle size categories reported in µg/m3 units
- The dust sensor technology used is particle size distribution with Laser Diffracted/Scattered Light.
- Dust-13 also measures ambient Temp and RH%
- Power supply: Micro-USB connector, 5V, 500 mA
- Works together with the e-Gate Cloud data platform with mobile phone connection and open API interface
- Optional, robust construction site sensor enclosure available