Archives: Projects

Corona Virus Scrubbing systems

The Problem

2020 studies have shown that aerosolised sub 5 micron COVID -19 particles spread and remain suspended in the air for up to 3 hours in non-ventilated and poorly ventilated spaces.

In addition, many hospital procedure rooms including ICU and theatres are normally positive pressure spaces designed to protect the patient from infection.  Some older cohort wards are not ventilated at all. This allows the virus to concentrate and spread.

Bio-safety experts consider face masks worn by frontline staff do not offer full protection against sub 5 micron virus particles.

Higher air effective change rates are known to dilute the aerosolised viral loading but this does not always work as zonal stagnation of air is a common problem.

An interesting article about to be published in July 2020 in CDC is starting to address the matter see:- https://wwwnc.cdc.gov/eid/article/26/7/20-0885_article

 

Virus scrubbing units have been adopted by a number of NHS trusts:-  Treliske Hospital Cornwall UK already have 8 units delivered as of 1st April 2020. The idea has now been adopted by Exeter RD&E and is being trialled at the Royal Berkshire hospital.

The solution

Healthcare staff, including those required to undertake close proximity care such as dentists and nurses can be better protected using 4 additional techniques:-

1) Virus Capture Aerosolised Covid-19 droplets are reduced by capturing virus at source or adjacent to the infected patient.

2) Directed air flow:- Large parts of the clinical space will be protected from the accumulation of virus by displacement (or shunt) ventilation. Here air is now moved away from medical staff past the patient.  As the air moves directionally, the aerosolised virus is entrained, sucked away and filtered out.

3) Dilution:- The virus concentration can build up such that sufficient virus will result in an infectious dose.  By providing a good air change rate within the space, the air is diluted such that after say 5 minutes after virus is present the air is clear.

2) Negative pressure:- The scrubber device can easily be set up to keep infectious spaces under negative pressure thus stopping contaminated air from escaping to other parts of the building.

To comply with the above objectives we have designed and manufactured a series of simple combined virus scrubbing modules using a very fine HEPA14 (ASHRAE MERV14 or 19) to catch and kill the virus. The design can also be used to keep the containment space under negative pressure.

We can in addition to HEPA filtration incorporate a powerful UVC light source to kill airborne virus.

The filter and super quiet fan are connected to lightweight flexible air ducts which can be quickly installed. The ducts will extract aerosolised virus from behind the patient.

Clean scrubbed air is reintroduced into space.

 

Ward and waiting room units

Fig 1 – Hospital ward application.

These larger scrubbing units filter up to 300 litres per second and are useful for spaces where it is know that there is a higher risk of aerosolise virus being present.  A variety of ducted systems can be designed as either temporary or permanent features of the space.

 

Dentist rooms

Fig 2 – dental room application.

Here a bell-mouth air intake, extracting up to 200 litres per second, is positioned adjacent to the patient. Any virus expelled is immediately sucked into the HEPA filter and captured. The time allowed to clear the air between patients would be in the order of 5 to 8 minutes.

 

Consulting rooms

Fig 3 – consulting room application.

By extracting the air, up to 200 litres per second, adjacent to the patient, any aerosolised pathogens present would be immediately captured in the filter. This cleaned air would be reintroduced on the other side of the consulting room adjacent to the clinician. The time allowed to clear the air between patients would be in the order of 5 to 8 minutes.  Waiting times between patients would be reduced from an hour to about 5 minutes.

 

In addition, the carbon filter located inside the scrubber will immediately remove any unpleasant order from the room.

The Units can also be fitted with ultra violet (UV) lighting tubes which will efficiently kill all bacteria and virus pathogens in the air. This is an optional feature which can be applied to all units mentioned above.

Each unit comes with the following features:

  • Fan speed controller.
  • An F7 pre-filter which ensures the HEPA filter has longevity
  • An on off switch
  • A indicator dial to notify when filter need changing
  • A control panel to allow you to switch the UV lights on and off as required
  • Zinc galvanised Internal surfaces, which creates a excellent  biocidal surface.
  • Wheeled casters with individual wheel locks for safety.
  • Acoustic lining to attenuate noise

(All units are professionally painted to allow for cleaning in a medical environment)

Availability

Scrubbing units are built to order. For the best results approximate dimensions or a photo of the room should be provided to optimise the room layout and the position of the ventilator.  Permanent solutions include the use of the space above the suspended ceiling to allow flexible ducts to be hidden.

We will advise on the duty required and price for the correct solution including additional UV sterilisation and ductwork components.

Camp Kernow

“Camp Kernow is a progressive environmental education site for young people in Cornwall and further afield.  The camp provides a real perspective into green energy, sustainable agriculture and responsible environmental recycling of waste.  Charlie Nicholson who runs the site has requested help from GPJ Consulting engineers who in turn have provided technical engineering support free of charge.  GPJ Consulting believe the millennial generation are left with an environmental legacy which they will have to deal with.  This includes responsible and economic energy usage, the need to reduce waste and to fully utilise low carbon technology.  In order to address the serious concerns about global warming the next generation need to be responsibly educated from a practical perspective.  We believe the activities at Camp Kernow go a long way in fulfilling this need.

 

GPJ Consulting fully support green technologies including anaerobic digestion, wind and solar generation, biomass energy and rainwater harvesting all of which are practically demonstrated at Camp Kernow.

 

“The very kind support of GPJ Consulting has been invaluable in the safe installation of a 1.5kW wind turbine at camp. The energy generated will power camp’s off-grid office and electric vehicle while demonstrating to young people how renewable energy technologies can provide clean energy to meet our needs.” Charlie Nicholson- Camp Kernow

Baltier Farm Anaerobic Digestion

GPJ Consulting Engineers are currently commissioned to oversee the construction, on-grid generation and RHI/FIT set up of a 450KW mixed plug flow anaerobic digester in Western Scotland.

Our engineers carried out site visits to inspect the construction and offer help and assistance with optimising the installation to take full advantage of the plant and equipment.

Digester feed stock was also modified during the commissioning process to ensure the highest possible digester yields.

Once up and running we assisted the Client with completion and verification of their Renewable Heat Incentive application and Feed in Tariffs to provide government payments for the energy produced.

Ships & Castles Leisure Pool

GPJ Consulting Engineers have produced a full Preventative Planned Maintenance Schedule for the landmark Ships & Castles Leisure Pool in Falmouth, Cornwall.

The PPM scheme commenced with a detailed site survey which established the condition of all M&E plant and equipment.

From this point our engineers were able to provide a tailored maintenance schedule to suit the current condition with a multiyear plan that not only covered standard maintenance regimes, but also provided scope for plant upgrades and enhancements.

The full PPM scheme was tendered to local and national contractors and on site works were overseen by GPJ’s engineers to ensure full compliance with the maintenance schedules.

Mid Devon District Council

GPJ Consulting Engineers have produced Planned Maintenance Schedules for a number of Mid Devon District Council’s property portfolio.

Office Buildings, Leisure Centres and Swimming Pools were all surveyed to check plant condition and to set a baseline from which the maintenance regime can be based upon.

A full maintenance schedule was produced for each building noting makes and models of plant and equipment. Manufacturers recommended maintenance schedules were cross referenced with the HVCA standard recommendation’s to maintain the plant in optimum condition.

Regular checks were carried out on site to ensure the maintenance was being carried out as necessary.

Ministry of Defence

GPJ Consulting Engineers were commissioned to carry out a full site Mechanical and Electrical Condition survey on 3 of the south west’s main Ministry of Defence shore based training establishments.

Teams of engineers visited every building on each site photographing and commenting on the condition of the plumbing, heating, ventilation, electrical and alarm systems.

The survey covered approximately 610 buildings and provided the facilities managers with a multiyear remedial plan along with typical rectification costs.

Mixed Plug Flow Anaerobic Digestion

Anaerobic Digestion is rapidly becoming a popular technology for breaking down organic matter into biogas. This biogas can then be utilised within generators to produce electricity.

Traditional anaerobic digestion plants are constructed at ground level and normally feature a number of tanks, storage vessels and other associated plant. This can be a blight on the landscape in particular sensitive locations.

GPJ Consulting Engineers have designed proposals for a number of discrete mixed plug flow digesters which are constructed below ground with minimal effect on the surrounding landscape. A feature of this particular design is the lack of moving parts within the digester, which simplifies operation, reduces maintenance and lowers installation costs.

Royal Cornwall Hospital’s Trust

Our engineers have been appointed AEs for the Trust since 2014 when the Trust only had 1 authorised person (AP) and 3 competent persons (CP). We are providing training for new APs and AEs by providing tailored training sessions to new staff members within the Trust to bring them up to the required level of knowledge.

We have provided guidance and consultation to the Estates operations team, carrying out regular practical plant inspections, annual maintenance audits and sign-off all new vent systems.

Working closely with the Trusts infection prevention and control (IPAC) team we offer practical guidance and effective control measures with respect to ventilation systems and their part in infection prevention within the Trust.

We have formed a ventilation users group to discuss all the Trusts ventilation issues and on-going service improvement. We are active participants at meetings.

We audit the Trust’s re-verification reports for all critical ventilation systems (i.e. operating theatres) and report our findings directly to the group with our recommendations for corrective measures where required.

We provide ventilation workshops with Trust clinical staff to raise their awareness of the ventilation systems within the hospital and how a simple change of use to a room could compromise the safety of patients and staff if the ventilation systems design is not assessed.

We offer bio-security expertise in relation to the control of infection and the design of the ventilation systems to prevent the spread of infection throughout a facility and also offer guidance to protect the Trusts maintenance staff for exposure to risk.

Drains are often neglected parts of the ventilation and harbour airborne pathogens. Hence the design and maintenance of drain vents are a very important part of our bio-safety work.

Risk mitigation is associated with cross infection and potential exposure to microbiological pathogens. Risk is elevated by poor ventilation or incorrect ventilation. Drainage systems including toilets pose a significant risk to certain patient groups. Correct design eliminates these problems.

Pumped Storage

A pumped storage power generation system utilises a body of water pumped to a height and released when required through hydro-electric turbines to generate a large amount of electrical energy over a short period to act as a buffer to assist the power grid with peaks.

Traditionally schemes like this have utilised multi-level bodies of water such as lakes and reservoirs to provide their energy source.

GPJ Consulting Engineers are actively researching and developing schemes which utilises redundant deep shaft mines to provide the high and low level storage. This minimises surface disruption.
By installing turbines into the mine shaft within a machine hall we can utilize the upper mine galleries or surface lake. Water can be released when required down the shaft, through the turbines and into the lower galleries of the mine.

During off peak periods the lower stored water can be pumped back to the upper galleries or lake and stored for future use.
A head of 500m with storage for 15,000 m3 of water will provide an installed capacity up to 50MW
(for 15 minutes)

Syphonic Roof Drainage

GPJ Consulting Engineers were asked by one of our long term Clients to propose a method of replacing the existing troublesome symphonic roof outlets with a new item. On the face of it, this appeared to be a simple challenge, however the Client could not allow the rooms and ceilings below the outlets to be disrupted. This prevented a traditional approach to renewing the drainage system.

GPJ Consulting Engineers carried out an accurate site survey and designed a new stainless steel roof drain unit that could be replaced from above maintaining system integrity, whilst minimising disruption to the office workers below.

GPJ Consulting Engineers worked closely with a local specialist contractor to oversee the fabrication of a prototype. This was successfully installed on site with the scheme being rolled out across the building.