FDDC in an operating theater in Dr. Roberto Gilbert Hospital, Wednesday 5th of September 2018

А STERISAFE® employee supervised the Full-Depth Disinfection Cycle in the children’s hospital Dr. Roberto Gilbert Elizalde, Guayaquil, Ecuador. ​

The disinfection cycle took place in one of the hopitals operating theaters. The operating theater had a volume of 115 m3.​

Samples were taken after manual cleaning, before FDDC and after the FDDC cycle. Please read the full report below, which will be visuality illustrating the approach and results with the aid of Hygicult® Total Plate Count (TPC).

The Full-Depth Disinfection Cycle by STERISAFE uses ozone to decontaminate the air and surfaces for bacteria, vira and fungi. After the disinfection is completed the STERISAFE reverses the ozone gas into breathable oxygen, removes remaining particles and the room is disinfected and safe to use.

This field test used Hygicult® TPC (Total Plate Counts) to illustrate visually the disinfection efficacy. The TPC plates show the reduction of the colony forming units (CFUs) by comparing before and after disinfection with FDDC results.

Samples were taken after manual cleaning before Full-Depth Disinfection Cycle. Next, a sample after the (60minutes disinfection time) FDDC at the very same location.

The pictures show the exact locations where samples were taken and the Hygicult® TPC results.

Each Hygicult® TPC plate has two sides, market in this resport as Side A and Side B.

STERISAFE is using Hygicult TPC from Orion Diagnostica (Finland) for its hygiene mapping. It is a reliable, economic, and easy-to-use on-site surface hygiene monitoring tests.

It is intended for general hygiene monitoring as most common bacteria, yeasts, and moulds can grow on it. The slide is covered on both sides with Total Plate Count (TPC) medium that supports the growth of the most common bacteria and fungi. The medium contains neutralising agents making the product suitable to be used in environments where disinfectant chemicals have been used. Each plates has two side of 9.8cm2 area each.

Hygicult is certified to be equivalent to the reference methods Trypticase  soy  agar  (TSA)  culture  plates  and  contact  plates. The certification has been made by NordVal Protocol 1, which complies with ISO 16140-2 1.

Each location is sampled twice. Results come after 4 to 5 days and are counted manually.

The Hygiene Mapping gives a general surface hygiene level of the room with a four colors code system. To determine the level, two factors are considered:

  • The level of contamination in CFU/sample.  Above 5 CFU, the surface is considered contaminated
  • The type of surface with a level of criticality. The higher the risk of cross-infection via the given surface, the higher the criticality.
Type of surface
CriticalityInterpretation
Very high risk of infection transfer if contaminated
High risk of infection transfer if contaminated
Moderate risk of infection transfer if contaminated
Low risk of infection transfer if contaminated
Level of contamination
Hygiene LevelInterpretation
>50% of surfaces contaminated or average contamination of >50 CFU/plates
Between 20 and 50% of
surfaces contaminated
Between 0 and 20% of surfaces contaminated
0% of surface contaminated

Total surface hygiene   
Poor HygieneModerate HygieneAcceptable HygieneExcellent Hygiene

Results from microbiological sampling on 5 locations in the operating theatre before cleaning:

AreasCriticalityResultsContamination level
High touch4 out of 5 samples were taken on high touch areas. 2 of 4 of these areas where considered contaminated, with an average contamination of 9 CFU/plate, leaving the contamination level moderate to acceptable.
Under operating table1 out of 5 samples were taken under the operating table. With 4 CFU/plate this leaves the contamination level acceptable.

The results from the Avance CS2 Pro display is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.

The results from the cupboard and scissors is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.

The results from the ICU 2085 monitor is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.

The results from the lamp above the operating table is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.

The results from under the operating table is depicted by the colony forming units (CFU’s) on the TPC samples.

Each picture is depicting a sample taken before (leftmost sample) and after (rightmost sample) the FDDC cycle.

The Full-Depth Disinfection Cycle in the 115m3 operating theater (OT) took 181 minutes (3h 1 minute).

The operating theatre achieves good results in the hygiene test, despite having some areas contaminated. It is clear however, that the results are significantly improved after the room have been disinfected with STERISAFE

The graph below depicts the results are after just one single disifection with STERISAFE PRO as opposed to manual disinfection.

Sample location
CFU's Before STERISAFE
Contamination level
Avance CS2 Pro display
8
Cupboard and scissors inside
10

Fanem ICU 2085 monitor
2
Lamp above operating table
0
Under the operating table
4

Sample location
CFU's After STERISAFE
Contamination level
Avance CS2 Pro display
1
Cupboard and scissors inside
1

Fanem ICU 2085 monitor
1
Lamp above operating table
0
Under the operating table
0