• March 22, 2022
  • Erny Niederberger

Cost comparison: hirst vs. automatic pollenmonitoring

How much does automatic versus traditional pollen monitoring cost in comparison?

In this blog post we venture a comparison of the costs of automated versus traditional pollen monitoring. We look at the initial costs as well as the long-term operating costs of traditional pollen counting with the “Hirst method” versus an automated solution for real-time pollen monitoring.

By the “Hirst method” we mean the use of an automatic volumetric spore trap described by J.M. Hirst in 1951. The process is based on the subsequent manual detection and counting of pollen under the microscope in the laboratory. This method is standardised according to EN 16868 : 2019 (Outdoor air – Sampling and analysis of airborne pollen and fungal spores for allergy networks – Volumetric Hirst method).

Costs of traditional pollen monitoring with Hirst

So let’s start with the analysis of manual pollen counting, which to date is still the most widely used pollen monitoring method in the world. First, we need to establish a baseline for costs. For this article, we have gathered information in exchange with experts and made a few assumptions. In the example shown, an average hourly rate for laboratory work in Germany is defined. The following table shows the cost structure:

Costs of traditional pollen monitoring with “Hirst method” in Germany

Average cost of an hour worked (gross wages and other labour costs) (Source Eurostat) 35.60 €/hour
Average weekly working hours in the country in 2019 (all employees) (source Eurostat) 40.2 hours
Assumption: number of days per year with pollen assessment 274 days
Assumption: workload for pollen counting and identification of a trap 25.0 % FTE
Working hours required for pollen counting and identification of a trap 393.2 hours/year
Costs for the manual evaluation of a pollen trap per year 13’998 €/year
Assumption: working hours for operation and maintenance of a pollen trap 16.5 hours/year
Labour costs for operation and maintenance of a pollen trap 587 €/year
Assumption: Consumables for operation and maintenance of a pollen trap 400 €/year
Total costs for operation and management of a pollen trap 14’985 €/year

The costs of working hours and working hours per week depend very much on the country and region. For the example we have used the data for Germany from Eurostat.

At the same time, we assume that the pollen load is evaluated during the entire pollen season of 9 months or 274 days per year. According to experts, the effort for counting the pollen on the adhesive strip of a Hirst pollen trap corresponds to a workload of 25 %. In addition, we have included 16.5 hours for the maintenance of the Hirst pollen trap and €400 for consumables. The annual recurring costs for a manual Hirst pollen trap are dominated by the labour costs for manual identification. In the example, this is €14,000 and another €1,000 for maintenance and consumables. It is noteworthy that these figures are linear and accrue every year. So there are no scaling effects in a measurement network with several stations.

Now, let’s look at the whole thing over a term of 10 years. At the beginning there are initial costs for the purchase of a Hirst pollen trap, which we estimate at about €5’000. According to our calculations, the annual costs for operation are €15,000. Thus, in our example we arrive at a total of €155’000 for a life cycle of 10 years. The following figure visualises the linear progression. The blue bar represents the deviation that can arise due to the different hourly rates and initial costs in other European countries. Additional costs for the recruitment of personnel and the training of specialists for pollen identification are not included.

Cost Hirst 10years
Lifetime costs of manual pollen identification with Hirst method for 10 years for Germany

How much does automatic pollen monitoring cost in comparison?

In this section we now consider an automatic pollen measurement system. The initial costs for a single system are in the range of €50’000 to €70’000. These are made up of the following items, for example:

  • Measuring instrument
  • Software for data management
  • Identification algorithms
  • Transport, installation, commissioning and training
  • administrative costs of the operators

It is worth mentioning that compared to traditional pollen monitoring, an automatic measurement network has scaling effects that reduce these costs. In the following example, five automatic systems are operated in one network and the costs are calculated down to one system. Furthermore, we assume that validated identification algorithms for the relevant pollen taxa are already available for Germany. Thus, new pollen taxa do not need to be trained. For the training and validation of new pollen taxa, one-time additional costs have to be added. After installation, continuous real-time measurement of pollen concentrations begins on site. The five systems run completely automatically from this point on.

The annual cost of an automatic pollen monitor from that moment on consists of the maintenance costs and the costs for data hosting. Since the measuring systems have a filterless design and do not require any consumables, there is no need for regular maintenance during the pollen season. They are also designed for a service life of at least 10 years. In addition to the annual on-site system maintenance, the maintenance costs also include software maintenance. This consists of security updates as well as improvements, bug fixes and functional enhancements to maintain the value of the systems. Another share is to be added for preventive maintenance with the help of remote monitoring. Likewise, there are non-negligible amounts for data hosting.

All the services mentioned thus add up to an amount of around € 8,000 per year per system. Here we consider a network consisting of five measuring stations. Additional costs arise for location, electricity and data transmission. We calculate annual recurring costs of €1,000. In our example, the total annual costs per system are €9,000.

How do the costs of traditional and automatic pollen monitoring compare directly?

Cost Automatic Hirst 10years
Lifetime cost comparison manual pollen counting (1 station) with automatic pollen monitoring (5 stations)

The green bar shows the total costs of an automatic pollen measurement system for a measurement network consisting of five systems. The blue bar shows the total costs of the “Hirst method” over the same period of 10 years.

It is relatively easy to see that the initial costs for the automatic system are significantly higher. However, the annual recurring costs of the automatic system are lower than those of the manual Hirst method. This shows that the total costs of the automatic system after several years of operation are similar to those of the Hirst method. Depending on the labour costs in the respective country and the configuration of additional services, the single, automatic system may even be more economical.

Especially when operating several systems in a monitoring network, further cost savings result compared to the manual measuring method. In addition to the cost savings, automatic pollen monitoring naturally brings many other advantages. The table below summarises a few examples in comparison with traditional pollen monitoring. However, what makes the manual method superior to the automatic one is that it is certified according to EN standards and there are many studies on it.

Further features of automatic and traditional pollen monitoring in comparison

Automatische Pollenüberwachung in Echtzeit Traditionelle Pollenüberwachung mit Hirst-Methode

Automatic pollen monitoring in real time

Traditional pollen monitoring with Hirst method
Pollen data in real time and without delay Pollen data only available with one-week delay
Time resolution of pollen concentrations of one hour. Push notification of allergic persons possible. Time resolution of the pollen concentrations of one day
Fully automatic operation 24 hours a day, 365 days a year Measurement for cost reasons only during 9 months per year (or less)
Measurement data can be used to improve pollen forecasting Manual data can only improve the pollen forecast to a limited extent because it is available too late.
Smaller measurement uncertainties at low pollen concentrations thanks to higher sampling volume Relatively large measurement uncertainty for small pollen concentrations
Cost reduction for networks through scaling effects No cost reduction for networks, as no scaling effects
Higher crisis resistance (fully automatic operation) Dependent on freedom of movement and human operators
Constant recognition quality through machine-based artificial intelligence Human factor: recognition quality depends on the operator
No standardisation (yet) Procedure Standardised according to DIN EN 16868:2019
New technology, still little experience Long-term measurement series available

Was this article helpful?

We hope this article has helped you understand the cost structures of manual and automated pollen monitoring in real time a little better. Are you currently interested in automatic pollen measurement? We would be happy to give you more detailed information about our solution for real-time pollen monitoring and provide you with an overview of our offers.

References

HIRST, J.M. (1952), AN AUTOMATIC VOLUMETRIC SPORE TRAP. Annals of Applied Biology, 39: 257-265. https://doi.org/10.1111/j.1744-7348.1952.tb00904.x

Hourly labour costs 2020 in Europe: https://ec.europa.eu/eurostat/statistics-explained/index.php/Hourly_labour_costs

DIN EN 16868:2019: Ambient air – Sampling and analysis of airborne pollen grains and fungal spores for networks related to allergy – Volumetric Hirst method; German version EN 16868:2019, https://webstore.ansi.org/Standards/DIN/DINEN168682019

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