scubalab reviews state-of-the-art breathers

12
S C U B A L A B ® R E V IE W E D
SCUBALAB REVIEWS
STATE-OF-THE-ART
BREATHERS.
NEW
SCUBALAB ONLINE
For more on how
ScubaLab tests regulators, including a detailed look at
REGS
WOULDN’T IT BE NICE TO DEMO every new regulator before
how we use the ANSTI machine,
committing your hard-earned cash? It is, after all, the most important
go to www.scubadiving.com/
piece of gear you’ll buy, which puts a lot of pressure on making the
bonus_2007_reg_test
right decision—and that’s where ScubaLab comes in.
We invited all major manufacturers to submit their new regulators (introduced within the last 12 months) for this review. After
inspecting them and reviewing the owners’ manuals we put them
on an ANSTI breathing simulator to measure the precise breathing
resistance a diver will encounter at four different depth/breathing rate settings that range from normal breathing at 132 feet to
extreme exertion at 198 feet. Then we turned the regs over to a
team of eight test divers to be your stand-ins. Their mission was to
rate each reg using a 1 to 5 scale in seven ergonomic performance
categories, from ease of breathing to comfort features. These divers
also made notes on each reg—what they liked and what they didn’t
like. We then polled our test divers to find out which reg in each
BY BILL KENDIG
price category offered the best combination of features, comfort
and performance and awarded these regs the additional honor of
being named a ScubaLab Testers’ Choice (see “Testers’ Choice &
Best Buy,” p. 73).
The complete results of all our tests are found in the charts on p.
98, and are summarized in the following reviews, which are presented
here in alphabetical order within price categories.
00
SCUBA DIVING
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PHOTOGRAPHY BY JOSEPH BYRD
J U LY 2 0 0 7
SCUBADIVING.COM
71
R E G U L A T O R S
O V E R
$ 5 0 0
APEKS
XTX200 Tungsten Swivel
P R O S : Perfect simulator
scores; well-designed user
adjustments; great hose swivel connection on the second
stage; cool-looking protective finish.
APEKS
XTX200 Status
CON: High price.
AQUA LUNG
Kronos
F I R S T S TA G E : This
compact, environmen-
P R O S : Compact first stage; simplified user
system on the Kronos pneumatically balanced
ments of the others. Our divers also gave the
tally sealed, over-balanced
adjustments; unique side-venting exhaust tee;
second stage directs all bubbles to the diver’s
Side-X exhaust system a unanimous thumbs-
diaphragm first stage is the
ACD dam on first-stage inlet.
right for clearer viewing. An added benefit is
up. The compact second stage was an easy
flagship regulator for Apeks—and it looks really
CON: Not environmentally sealed.
that warm air passes over the second stage valve
breather, stayed dry in all positions and was
cool to boot. The hardened tungsten PVD finish
F I R S T S TA G E : The Kronos balanced-dia-
and hose, fighting freeze-up in cold water. The
easy to clear.
while the more streamlined XTX200 first stage
is not just for show, it also protects the reg from
phragm first stage offers a full contingent of four
new Dual Cam control simplifies adjustment by
T H E A N S T I R E P O R T: Work of breathing
user adjustments; built-in electronic intermediate
is available with a DIN connection.
the elements. Four low- and two high-pressure
low-pressure and two high-pressure ports, giv-
combining the venturi and breathing resistance
scores fell into the Excellent category for the
pressure gauge; reversible hose configuration.
S E C O N D S TA G E : The pneumatically bal-
ports are angled for comfortable hose routing
ing you more flexibility in hose routing and the
knobs into one easy-to-find lever. While the
test that most closely represents recreational
C O N S : High price; large first-stage (XTX50
anced second stages are identical except for a
and there’s a brass plaque affixed to the first
option to use both a transmitter and pressure
range of adjustment is small, it does the job of
diving and the Very Good category for the more
Status).
few cosmetics—the XTX200 has chrome trim,
stage for a distinct appearance. It’s nitrox-ready
gauge hose. The first-stage opening features
stopping freeflows at the surface and fine-tuning
extreme tests. Close inspection of the breathing
F I R S T S TA G E : These are the first regs to
the XTX50 does not. Well-designed adjustments
right out of the box for mixes up to 40 percent
Aqua Lung’s Auto-Closure Device (ACD), which
breathing performance underwater. The Kronos
loops shows that in these high-volume breath-
feature a built-in electronic intermediate pres-
include a large control knob with a wide range
and shares the same smooth-breathing perfor-
closes the inlet to water intrusion whenever the
comes with both a Comfo-Bite mouthpiece and
ing situations and at depths to 198 feet, the
sure gauge, complete with an LCD screen that
of travel for taking breathing resistance right
mance as the regular XTX200.
reg is off a tank. Another nice touch: The yoke
a standard spare.
reg’s inhalation effort was very stable while the
indicates if the pressure is “HI,” “LO” or “OK”
to the edge of cracking effort, and a ratcheting
S E C O N D S TA G E : The Tungsten finish is
knob is covered with soft rubber for an easier
T E S T D I V E R S S A I D : “The Dual Cam lever
exhalation effort increased only slightly as the
before every dive. The electronics also track the
venturi lever that lets you tune out freeflows.
also found in the grill of the second-stage cover
grip with wet hands.
was glove-friendly and prevented surface free-
tests got more challenging.
date and hours of use to indicate when it’s time
Both second stages also feature a reversible
and on the adjustment knob. It has all the same
S E C O N D S TA G E : The new Side-X exhaust
flows,” wrote one test diver, echoing the com-
PRICE: $569.
for routine service. Beneath the digital brain
hose configuration.
adjustment features found on the other XTX
are two different versions of an over-balanced,
T E S T D I V E R S S A I D : The large ratcheting
second stages, plus it comes standard with
environmentally sealed diaphragm first stage
venturi and the adjustment knob are easy to
a great new hose swivel connection that test
that has plenty of brawn. Both regs offer four
find and use, even with gloves. Many test divers
divers loved.
low-pressure ports and two high-pressure ports
also liked the Comfo-Bite mouthpiece. Clearing
T E S T D I V E R S S A I D : “It felt like the hose
for convenient hose routing (low-pressure ports
was easy and the purge button was effective
wasn’t even attached,” wrote one test diver
are on a rotating turret on the XTX50; angled
without blasting fillings loose. Breathing was
commenting on the swivel connection. As with
on the XTX200). Both regs come factory ready
very dry in all positions, and there was no drop
the other XTX second stages reviewed here,
A: We award the Testers’ Choice logo to the
for nitrox mixes up to 40 percent. The XTX50
in performance in various positions.
the large control lever and adjustment knob
gear that our team of divers vote as their
A: Not at all. As you can see from the individual reviews and the
first stage comes in a bigger, bulkier package,
T H E A N S T I R E P O RT: Both regs aced the
were also a hit.
favorite combination of fit, features and perfor-
charts on p. 98, every regulator tested performed admirably on
breathing machine panel with a remark-
T H E A N S T I R E P O R T: Another perfect
mance based on their extensive in-water use.
the breathing machine, and all were able to stand up to the most
ably stable performance regard-
score. The addition of the swivel made no sig-
less of depth or demand.
nificant difference in breathing performance.
Q: How do you determine Testers’ Choice ratings?
divers gave any reg in any category was a Good rating. The results
P R I C E : $847 for the XTX50
PRICE: $965.
A: While in the past we used a complicated points-based system to
of each review stand on their own and should be read carefully and
determine what gear earned our coveted Testers’ Choice rating, for
completely. Testers’ Choice is merely an additional tool to help you
2007 we simplified the process. At the conclusion of our in-water
analyze the results and make an informed buying decision.
APEKS
XTX50 Status and XTX200 Status
PROS: Perfect simulator scores; well-designed
Status; $990 for the XTX200
Status.
Testers’ Choice & Best Buy
Q: What is a ScubaLab Testers’ Choice?
Q: Does not earning a Testers’ Choice mean gear
is substandard?
punishing tests. In the ergonomic evaluations, the lowest score test
testing, we divided the regs into their respective price groups and
polled our test divers with one final question: “Which one would
APEKS
XTX50 Status
72
SCUBA DIVING
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Q: What is a ScubaLab Best Buy?
you buy?” It’s fascinating to see the wheels turning as each test
A: While Testers’ Choice is based on the vot-
diver calculates all the pros and cons and comes up with their indi-
ing of test divers, Best Buy is awarded at the
vidual answers.
discretion of the ScubaLab staff. We award
this logo to the gear that we think is a particularly good combination of performance and price.
J U LY 2 0 0 7
SCUBADIVING.COM
73
R E G U L A T O R S
O V E R
$ 5 0 0
R E G U L A T O R S
AT O M I C A Q U AT I C S
U N D E R
$ 5 0 0
MARES
ST1
Proton 12 Metal
PROS: Lowest overall work of breathing; corrosion resistance at a lower cost than titanium; great
P R O S : High performance at a reasonable
Design (VAD) directs air to the diver through a
second-stage swivel for added comfort.
price; new tri-material first-stage valve; proven
bypass tube from the valve seat to the mouth-
CON: High price.
diver-friendly design.
piece. The large front-cover purge is smooth
FIRST STAGE: The ST1 is a balanced-piston first stage turned from 316 stainless steel that offers
CON: Narrow exhaust tee allows some bubble
and easy to find, even with gloved hands. The
interference.
orthodontic mouthpiece is soft and comfort-
FIRST STAGE: The Proton 12 Metal has been
able and the exhaust tee follows the shape of
one of Mares’ best breathing, balanced-dia-
the regulator, but allows greater-than-average
greater strength and corrosion resistance than brass regulators at a significantly lower cost than
titanium. It offers four low-pressure ports on a swivel turret with a fifth port on the end of the first
DIVE RITE
Hurricane
stage for easy hose routing, plus two high-pressure ports.
OMS
R250 High Performance
S E C O N D S TA G E : The ST1 delivers high performance with a dose of comfort thanks to a
P R O S : Compact tech-friendly reg; well-
phragm regulators for years, and it’s still going
bubble interference.
P R O S : Environmentally sealed and rugged;
well-designed mouthpiece and Atomic’s Comfort Swivel. It also features all the usual Atomic
machined user adjustments; dry breather in
strong. What’s new is the “tri-material” first-
T E S T D I V E R S S A I D : It’s hard not to like a
nice adjustment knob; easy clearing.
features—Automatic Flow Control (AFC), a self-adjusting venturi effect that increases breathing
all positions.
stage valve, made of brass and two different
light, compact and easy-to-use reg. The Pro-
CONS: Small mouthpiece, some bubble inter-
performance as you descend; the Rapid Adjustment Knob, which allows the user to de-tune the
CON: Mouthpiece too small for some.
polyurethane compounds. It’s designed to last
ton Metal delivers easy, dry breathing without
ference.
reg for surf entries or octopus use; a flexible purge cover; and the Seat Saving Orifice, which helps
FIRST STAGE: The new Hurricane from Dive
longer and perform better than previous ver-
the need for user adjustments, and the reg is
FIRST STAGE: OMS uses an environmentally
maintain the reg’s peak performance over time. Inside the second stage, the entire valve body and
Rite is a cyclone of air in a small package. The
sions. It also has the Dynamic Flow Control fea-
comfortable in the mouth. All test divers com-
sealed balanced-diaphragm first stage that is
lever of this pneumatically balanced second stage is made of corrosion-resistant titanium.
first stage is an over-balanced diaphragm that
ture, a dedicated low-pressure port that helps
mented on the ease and function of the large
tech-ready with a DIN connection and nitrox
TEST DIVERS SAID: Divers thought the ST1 was one of the “smoothest breathing” regulators of
is cold-water-ready down to 36F, nitrox-com-
deliver big air to your primary second-stage
purge saying it was “smooth and powerful.”
capabilities up to 40 percent. This compact
the bunch and gave it the highest ergonomic scores of all the regulators in this review. The comfort
patible up to 40 percent, and comes standard
hose for easy breathing.
T H E A N S T I R E P O R T: The Proton Metal
performer provides four low-pressure and two
swivel helped boost comfort scores and test divers had praise for the user control knob and soft
with a DIN connection. Angled ports put hoses
S E C O N D S TA G E : The Proton Metal is the
earned Excellent breathing machine scores
high-pressure ports, angled for easy routing.
purge cover. This reg also received the highest score for Ease of Breathing and was the only reg
where you want them with two high-pressure
smallest second stage in this test group, and
across the board, another reason this regulator
SECOND STAGE: The R250 second stage
rated Excellent by test divers for dryness. When we polled our test divers for their top reg in the
and four low-pressure fittings. A bright red
its solid metal construction makes this reg well
is still going strong.
is light and offers user adjustments for venturi
price category, the ST1 was a clear Testers’ Choice (see “Testers’ Choice & Best Buy,” p. 73).
cap protects the first stage against overhead
suited to cold-water diving. The Vortex Assisted
PRICE: $450.
and breathing resistance control. The large
T H E A N S T I R E P O RT: While several regs in this review earned perfect breathing machine
scrapes and aids in diver recognition.
adjustment knob can dial you right to the edge
scores on our 1 to 5 scale, the ST1 can boast the lowest overall work of breathing in every one of
S E C O N D S TA G E : The pneumatically bal-
of freeflow for crisp cracking effort. The Dive/
our ANSTI tests.
anced second stage offers multiple adjust-
Predive venturi switch is easy to find—on top,
PRICE: $899.
ments to fine-tune your dive. A large red
just in front of the mouthpiece—but it’s smaller
venturi control lever puts a stop to surface
than most levers in this test group. The small
freeflows and is easy to use with gloves. The
exhaust tee is streamlined, but didn’t wrangle
breathing resistance knob offers a wide range
bubbles as well as others tested.
of adjustment to dial in your preferred flow as
TEST DIVERS SAID: Testers said the regu-
you descend. A comfortable mouthpiece and
lator was easy-breathing and dry in most posi-
a wide exhaust tee are a nice touch.
tions. Some thought the mouthpiece was a
T E S T D I V E R S S A I D : Breathing adjust-
little small, but most liked the “huge range of
ments were “smooth and effective,” offering
adjustment” the regulator had to offer. Clear-
“a well-machined feel.” Our test divers also
ing was smooth and easy both by exhaling and
said the reg clears easily with a powerful purge
purging, though the front purge cover was “a
action. The wide exhaust tee did a nice job
little stiff.”
of directing bubbles away, and breathing was
T H E A N S T I R E P O R T: The R250 earned
dry in all positions. The venturi control lever
Excellent breathing scores at the first test point.
prevented surface freeflows and opened up
At greater depths and breathing
nicely underwater. While the mouthpiece is
rates the regulator’s work of
soft and comfortable, it was a little small for
breathing numbers fell into
many of the testers.
the Good category across the
THE ANSTI REPORT: The Hurricane deliv-
board.
ered an Excellent performance in the test that
PRICE: $418.45.
most closely replicates recreational diving and
Very Good scores in the more extreme tests.
PRICE: $599.
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SCUBA DIVING
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SCUBADIVING.COM
75
R E G U L A T O R S
U N D E R
$ 5 0 0
S P E C I A L T Y
R E G U L A T O R
APEKS
Tek3 XTX50
P R O S : Comes in right- and left-side
S C U B A P RO
S555
configurations for twin cylinders; environmentally sealed; excellent breathing
performance.
CON: Port configuration is not favorable
SCUBAPRO
for single-tank diving.
MK11/R395 and MK11/S555
F I R S T S TA G E : The Tek3 first stage is
PROS: Excellent performance at a budget price (MK11/R395);
SC U B A P R O
MK11
the first regulator designed specifically for
twin cylinders, offering one high-pressure
compact first stage; nice second-stage adjustment; smooth and dry-
port and three low-pressure ports, all on
breathing in all positions.
one side. Consequently, the Tek3 is made
CON: Some bubble interference.
in right- and left-hand versions. It is avail-
FIRST STAGE: The MK11 first stage was the smallest of the test group
able in DIN or yoke configurations and
but held its own, putting up some of the best test scores recorded in this
comes nitrox-ready up to 40 percent. It’s
review. This over-balanced diaphragm first stage features two high-pressure and four low-pressure
over-balanced and environmentally sealed
ports, two of which are marked “HFP” for pumping out 15 percent greater air flow. Convert to
for the most demanding conditions.
a DIN connection and you have the makings of a compact tech rig. The big surprise is that the
SECOND STAGE: The XTX50 second
MK11/R395 came in with the lowest price ($384) but with some of the highest performance, earn-
stage is pneumatically balanced, with
ing our Best Buy recommendation.
significant user adjustments and offers
SECOND STAGES: The R395 second stage is light and simple with just the VIVA venturi to adjust.
reversible hose configuration. The resis-
It uses a large control knob in front of the mouthpiece that’s clearly marked “Dive/Predive.” Inside
tance adjustment knob is large and offers
the case are a new lever and diaphragm that are designed to reduce friction. The low-pressure
a wide range for fine-tuning. The indexed
hose can be configured on either the right or left side to customize your rig and the flexible cover
venturi control lever lets you ratchet up
allows for easy purging. The S555 second stage is pneumatically balanced, which translates into
the flow on descent and block unwanted
lower cracking effort at depth. The case body and valve lever assembly are designed to prevent
freeflow on the surface. A wide exhaust
freeze-up and it has the same excellent dive/predive switch as the R395.
tee keeps bubbles out of view and can
TEST DIVERS SAID: Our divers found both regs to be smooth and easy breathers. The easy-
be exchanged with a smaller one for use
to-locate front purge covers were effective. The mouthpiece was comfortable for most while some
as a streamlined octopus.
bubbles interfered with viewing in certain positions. Breathing was affected in certain head-up
TEST DIVERS SAID: The Tek3 was a
positions with the R395, but not as much with the balanced S555 second stage. Both regulators
smooth breather and dry in all positions.
breathed dry in all attitudes. Most telling: test divers voted the MK11/S555 their Testers’ Choice
User adjustments are “easy to find and
for regulators under $500.
operate.”
T H E A N S T I R E P O R T: The
T H E A N S T I R E P O R T: The Tek3
breathing machine loved these
XTX50 received Excellent scores in all
regulators. Work of breathing was
breathing machine tests.
Excellent in all tests, and the regs
P R I C E : $1,450 for the Tek3 Complete
turned in almost identical results.
set (left- and right-side Tek3 first stages,
PRICE: $384 for the MK11/R395
two XTX50 second stages, a two-meter
and $489 for the MK11/S555.
hose, a standard hose and a regulator
necklace); $925 for a matched pair of
Tek3 first stages.
SCUBAPRO
R395
76
SCUBA DIVING
J U LY 2 0 0 7
I
N
D
E
P
T
H
3
DIFFERENT
POSITIONS
DIVES DRY
BUBBLE
INTERFERENCE
CLEARING
BLOW/PURGE
COMFORT
ADJUSTMENTS
A > 37.5 RMV @
132 fsw
B > 75 RMV
@ 132 fsw
C > 62.5 RMV @
165 fsw
D > 62.5 RMV @
198 fsw
$965
Ltd.
Lifetime
EASE OF
BREATHING
www.aqualung.com
Ltd.
Lifetime
FACTORYREADY NITROXCAPABLE
APEKS XTX200 Tungsten Swivel
$990
2ND
STAGE
ADJUSTMENTS
www.aqualung.com
2ND
STAGE
APEKS XTX200 Status
$847
5=EXCELLENT: A total WOB of 1.05 j/l or
PORTS
www.aqualung.com
Ltd.
Lifetime
ments into scores on a 2 to 5 scale as follows:
1ST STAGE
APEKS XTX50 Status
ANSTI BREATHING
SIMULATOR RESULTS
MADE IN
OVER $500
WARRANTY
TEST DIVER RATINGS OF
ERGONOMIC PERFORMANCE
PRICE
REGULATOR FEATURES
UK
Over-Balanced
Diaphragm
2 HP
4 LP
Pneumatically
Balanced
Resistance
Knob RVS*
Up to 40%
4
4
4
4
4
4
4
5
5
5
5
UK
Over-Balanced
Diaphragm
2 HP
4 LP
Pneumatically
Balanced
Resistance
Knob RVS*
Up to 40%
5
4
4
4
4
4
4
5
5
5
5
UK
Over-Balanced
Diaphragm
2 HP
4 LP
Pneumatically
Balanced
Resistance
Knob RVS*
Up to 40%
5
4
4
4
4
4
4
5
5
5
5
Up to 40%
4
3
4
5
4
4
4
5
4
4
4
$569
Ltd.
Lifetime
France
Balanced
Diaphragm
2 HP
4 LP
Pneumatically
Balanced
Dual-Cam†
(venturi/resistance)
$899
Ltd.
Lifetime
USA
Balanced
Piston
2 HP
5 LP
Pneumatically
Balanced
Resistance
Knob
Up to 40%
5
4
5
4
4
4
4
5
5
5
5
$599
Ltd.
Lifetime
France
Over-Balanced
Diaphragm
2 HP
4 LP
Balanced
Resistance
Knob Venturi Lever
Up to 40%
4
4
4
4
4
4
4
5
4
4
4
$450
Ltd.
Lifetime
Italy
Balanced
Diaphragm
2 HP
4 LP
Unbalanced
N/A
Up to 40%
4
3
4
3
4
4
N/A
5
5
5
5
$418.45
1 Year
USA
Balanced
Diaphragm
2 HP
4 LP
Unbalanced
Resistance Knob
Dive/Pres-Dive Switch
Up to 40%
4
3
4
3
3
3
3
5
3
3
3
$384
Ltd.
Lifetime
Italy
Over-Balanced
Diaphragm
2 HP
4 LP
Unbalanced
VIVA**
Up to 40%
4
3
4
3
4
4
3
5
5
5
5
$489
Ltd.
Lifetime
Italy
Over-Balanced
Diaphragm
2 HP
4 LP
Pneumatically
Balanced
VIVA**
$1,450 (2 complete
regs); $925 (LH and
RH first stages only)
Ltd.
Lifetime
UK
Over-Balanced
Diaphragm
1 HP
3 LP
Pneumatically
Balanced
Resistance
Knob RVS*
AQUA LUNG Kronos
www.aqualung.com
ATOMIC AQUATICS ST1
www.atomicaquatics.com
DIVE RITE RG3500 Hurricane
www.diverite.com
less.
4=VERY GOOD: A total WOB of 1.06 to
1.55 j/l.
3=GOOD: A total WOB from 1.56 to 2.25 j/l.
2=FAIR: A total WOB of 2.26 to 3.0 j/l.
Ergonomic Tests:
The Human Factor
Breathing machines tell only half the story. To
gauge the ergonomic traits of regulators, we
use a minimum of six test divers. Each diver rates
each reg for user-friendliness in seven areas:
» EASE OF BREATHING: How well a regu-
UNDER $500
MARES Proton 12 Metal
www.mares.com
OMS R250 High Performance
www.omsdive.com
SCUBAPRO MK11/R395
www.scubapro.com
SCUBAPRO M
MK11/S555
www.scubapro.com
lator delivers air in the standard swimming
position.
» DIFFERENT POSITIONS: How the regulator breathes when the diver is in a heads-up or
Up to 40%
4
3
4
3
4
4
3
5
5
5
face-down position.
5
» DRYNESS: Does the regulator breathe wet
5
» BUBBLE INTERFERENCE: Considered
SPECIALTY REG
or dry in both a normal swimming position and
odd swimming positions?
APEKS Tek3 XTX50
www.aqualung.com
Up to 40%
4
4
ANSTI Breathing
Simulator
4
4
4
4
5
5
5
while looking down, straight ahead, up at a
†Dual Cam (combines venturi control with breathing resistance control) * Reversible Venturi System ** Venturi Initiated Vacuum Assist
How We Test
Regulators
4
Rating System: 5=Excellent 4=Very Good 3=Good 2=Fair 1=Poor
45-degree angle and straight up.
» EASE OF CLEARING: Divided into two
All simulator tests are performed at a supply
» COLUMN B 75 RMV @ 132 fsw. An extreme-
uses this RMV/depth as its benchmark. For this
pressure of 725-760 psi. If a regulator can per-
ly aggressive breathing rate at the maximum
reason, it’s also the depth and breathing rate
Our test parameters state that the highest
purge button, and how forceful is the purge?
form well at this supply pressure, it will perform
recreational diving depth. A diver in excellent
most commonly used by manufacturers to test
inhale or exhalation pressure experienced by
2) How much force is required to clear the regu-
as well or better at higher supply pressures.
condition can breathe at 75 RMV for about one
regulators. This is a very aggressive breathing
the “diver” should never exceed 25 millibars
Here are the tests and what they represent:
minute. This test represents how a reg might per-
rate. A recreational diver in excellent condition
or a total WOB of 3 j/l. If a reg exceeds either
» COMFORT: Test divers rate the comfort of
form with a single diver breathing at an extremely
chasing a bat ray through open water would
parameter, it “fails” our test, but that doesn’t
the mouthpiece, the feel of the second stage in
heavy work rate. It also serves as a loose simula-
probably be able to maintain 62.5 RMV for only
mean that it stops delivering air—only that the
a few minutes.
breathing resistance at some point in the cycle
» ADJUSTMENTS: Are adjustments easy to
is higher than what is common for most mod-
find, grip and turn? Do they do their job in a
ern regulators.
reasonable manner?
performance.
parts: 1) How easy is it to find and use the
lator using the blowing method?
The ANSTI machine is the international industry
» COLUMN A 37.5 RMV @ 132 fsw. A some-
standard for scientifically evaluating a regula-
what aggressive breathing rate at the maxi-
tion of the stress a reg would be under if two
tor’s performance. It measures a regulator’s
mum recreational diving depth. A physically
divers were breathing off the same first stage in
» COLUMN D 62.5 RMV @ 198 fsw. This is the
work of breathing (WOB) in joules per liter (j/l)
fit recreational diver might breathe at this rate
an air-sharing situation. Only the U.S. Navy and
U.S. Navy’s Class A test depth and breathing
for each complete inhale/exhale cycle. We test
while swimming a long distance. (A relaxed
ScubaLab use this breathing rate to help identify
rate, although we use a lower supply pressure
A machine as accurate as the ANSTI simu-
regulators at four different RMV/depth com-
diver on a drift dive will probably be breathing
the outer limits of a reg’s performance.
lator can accurately differentiate j/l measure-
Performance is recorded using both numeric
at 22 RMV or less.) A diver could theoretically
» COLUMN C 62.5 RMV @ 165 fsw. All regs
(725-760 psi). We conduct this extreme test (no
binations (RMV stands for Respiratory Minute
diver should ever be breathing this aggressively
ments to tenths and even hundredths of a
scores on a 1 to 5 scale (5=Excellent, 4=Very
Volumes, basically the amount of gas that can
maintain 37.5 RMV for five minutes or longer
sold in the European Common Market must
at this great a depth with this little air left in
point. Human divers, however, can’t. For the
Good, 3=Good, 2=Fair, 1=Poor) and written
be ventilated through the lungs in one minute).
without becoming significantly winded.
pass a test standard known as EN250, which
his tank) to explore the outer limits of a reg’s
sake of simplicity, we translate j/l measure-
comments.
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the mouth, hose lengths and stiffness.
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