Data on rebreather accidents is needed by all involved with
rebreathers, for developing safety cases and for business
The database published here is maintained by Deep Life
Group as part of our Group Functional Safety
management. It comprises 4 categories of information:
- Comprehensive database of fatal rebreather accidents.
- Tools and example data enabling the significance of
accidents to be assessed statistically.
- Training Material on rebreather accident investigation
and associated data.
- Summary of incidents and accidents for training
Please report any new accidents or serious incidents to the
Coordinator at Deep
Paper revealing the
dichotomy within the sports rebreather industry,
where limited budgets result in some companies
spending on marketing at the cost of engineering,
and the actual consequences of those decisions.
Rebreather Fatal Accident
Database to 23rd January 2021 with analysis
The public extract of the database of Rebreather Fatal
Accidents and analysis, listing 568 of the confirmed
rebreather fatal accidents. Manufacturers can use this
data to improve designs, instructors can use it to
improve training, and divers can learn from it too.
This list names the divers where these are in the
public domain, to enable the accuracy of the list to
be verified more easily by third parties. The main
lessons for divers are:
BEFORE YOU SET OUT TO GO DIVING:
PRE-DIVE CHECKS BEFORE EVERY DIVE:
- Check your rebreather. Diving non-CE rebreathers
means the diver may be diving an entirely untested
product regardless of how reputable the brand name
is. Untested rebreathers generally have lethal
design faults. Only dive CE rebreathers certified
by reputable agencies such as SGS or DEKRA.
- Check oxygen cells every 3 months with a cell
checker, and look after them.
- Change your scrubber within the
manufacturer's stated endurance for the dive
profile you plan with either a Micropore
EAC, Draeger Divesorb or Molecular Products
Sofnolime - do not use other scrubber materials,
particularly do not use medical absorbant, e.g.
- Always replace your O2 cells after a year of
service,or within 18 months after
manufacture - whichever comes first.
- Always have eCCR electronics serviced
annually even though manufacturers generally
do not require this. Essential safety corrections
are made during annual servicing.
- Never go solo rebreather diving: it is
not Open Circuit so the diver is unaware of
exactly when a rebreather fails.
WHEN DIVING any rebreather with electronics:
- Do all predive checks, and never dive a
rebreather that fails any check or that you have
not fully checked or that you know to be faulty
in any way.
- Key Check: Before every dive unplug the hoses
from the scrubber or counterlungs, check each of
the two one-way valves work, then plug the hoses
back in. If you are not sure how to check the
valves in-situ, then do not dive: ask another
rebreather diver to demonstrate and then practice
doing it until it is second nature.
- Key Check: Do both positive and negative
pressure tests. They should hold solid.
- Pre-breathe for at least 5
minutes to check your PPO2 is under control and
CO2 scrubber is working.
IF REBREATHER SHOWS AN ALARM OR MALFUNCTIONS:
- Look at your PPO2 on entry,
- Look at your PPO2 at least every minute on
- Look at your PPO2 at least every 4 minutes on
- Look at your PPO2 continuously during ascent.
- If your ALV (ADV) fires when you are not
descending, immediately inject a burst of O2
manually and do then do a flush to check your
controller is working and the displayed PPO2 is
correct. The ALV may be giving you your only
warning that the loop is becoming hypoxic.
- !! Never ascend on a rebreather if you cannot
see your PPO2. !!
- Always use rebreathers as pure oxygen units when
near the surface. Do not exceed 8m on pure oxygen
(a PPO2 of 1.6 if flushed less than 5 times).
- Keep alert for CO2 problems: increasing
breathing rate, fear or discomfort. Bail out immediately
you suspect there may be any CO2 problem.
- !! When a diver aborts a dive, for any
reason, the buddy MUST stay with him. It is the
time when the diver will likely most need a
buddy. Abandoning a diver aborting a dive may be
- Inject Make-up-gas (DIL) manually, then
Hypoxia kills without warning, so flushing should
be an automatic reaction drilled into you when a
problem occurs. If you suspect hypercapnia (excess
CO2) then bail out first, as you will not be able
- Do NOT ascend.
- Do NOT continue on RB without injecting gas
- If in doubt, bail out. If you do not
know your PPO2, then you must bail out
immediately: your life depends on it.
Risk Analysis Toolkit with
Sports Rebreather Database. Updated to 9th May 08
The toolkit enables different types, models and
versions of rebreather to be compared for safety based
on observed accidents. The spreadsheet also provides
tools for the assessment of rebreather accident risk
and potential liability. Excel macros must be enabled
to use this toolkit. A database for the sports
rebreather market is provided as an example, from
which is calculated the global sports rebreather
market size, revenue, accident risk and liability to
net margin. The database is also used to illustrate
how safety can be quantified, comparing the risk of
using mCCR versus eCCR as one example and the changes
to particular rebreather models as another. Changes
may including training and use.
Note: Commercial, Military and Professional
rebreathers have a much lower risk, and data on these
is provided under Non-Disclosure to companies working
with Deep Life Ltd.
Analysis: a short tutorial guide (59KB)
A short tutorial guide on the main steps in
investigating a rebreather accident, for use as
forensic training material.
How Rebreathers Kill People
Incident reports showing some of the critical failures
in rebreather design, and the actions that need to be
taken to address them.
Effect of water ingress on
the breathing resistance of scrubbers using
granular CO2 absorber (175KB)
Forensic report on the effect of water ingress on
breathing resistance in a typical granular scrubber.
Report enables packing to be assessed in rebreathers
recovered after an accident where the equipment is