Ventilation requirements - FACTS for Makers
COVID-19 response: searching for emerging market ventilation systems
There is finaly some secification what a emergency ventilation system MUST fulfill
This is what makers MUST pay attention to. Please refere to: https://www.disabilityinnovation.com/news/frontier-tech-4-covid-action-emerging-market-ventilation-systems
From this website:
There is a detailed list of requirements on the application form itself, with a quick overview noted below. The RMVS must…
- Be reliable. It must work continuously without failure (100% duty cycle) for blocks of 14days — 24 hours a day. If necessary, the machine may be replaced after each block of 14 days x 24 hours a day use.
- Provide at least two settings for volume of air/air O2 mix delivered per cycle/breath. These settings to be 450ml +/- 10ml per breath and 350ml +/- 10ml per breath.
- Provide this air/air O2 mix at a peak pressure of 350 mm H2O.
- Have the capability for patient supply pipework to remain pressurised at all times to 150mm H20.
- Have an adjustable rate of between 12 and 20 cycles/breaths per minute.
- Deliver **at least 400ml of air/air 02 mix in no more than 1.5 seconds.**The ability to change the rate at which air is pushed into the patient is desirable but not essential.
- Be built from O2 safe components to avoid the risk of fire and demonstrate avoidance of hot spots.
- Be capable of breathing for an unconscious patient who is unable to breathe for his or herself. Ability to sense when a patient is breathing, and support that breathing is desirable but not essential.
- Be able to supply pure air and air O2 mix at a range of concentrations including at least 50% and 100% Oxygen. Oxygen shortages are not expected, but the ability to attach a Commercial Off The Shelf (COTS) portable O2 concentrator machine may be a useful feature.
- Support connections for hospital Oxygen supplies — whether driven by piped or cylinder infrastructure
- Be compatible with standard COTS catheter mount fittings (15mm Male 22mm Female)
- Fail SAFE, ideally generating a clear alarm on failure. Failure modes to be alarmed include (but are not limited to) pressure loss and O2 loss.
Notes form openmedical.earth:
- If you handle air with high oxygen percentage like 80% you MUST take into account that oxygen is a very reactive gas. If your pipe system has some leakage it is very likely that your hardware will oxidize quickly. This might be a challenge for copperbased circuit boards!
- running a venilator for 14 days, 24 hours a day with 12 to 20 cycles/breaths per minute means: your ventilator MUST work reliable for 240.000 to 400.000 breath/cycles -> that's quite an impressive number!