Since 1955; now in our 64th year of diving safety & fun ... · 8/8/2019 · was the cave map. Significant work to de-velop vector maps of different cave systems ... 2014. Car wash

1 | The Aqua Tooter August, 2019

www.aquatutus.org Since 1955; now in our 64th year of diving safety & fun August 2019

Since 1958... a publica�on from the Aqua

Tutus Diving Club, a non-profit organiza�on

established to promote Water Safety and to

further the sport of SCUBA Diving.

MEETING SCHEDULE General Club Meeting: First Thursday of Every Month at 7:30 p.m. (except December, no meeting) Board of Directors Meeting: Third Thursday of Every Month at 7:00 p.m. (except December, no meeting) Location: Ricky’s Sports Theatre & Grill 15028 Hesperian Blvd. San Leandro, CA 94578

UPCOMING CLUB HIGHLIGHTS

Sept 8-10: 3-day Vision trip to Channel Is. October 12: Full Moon Club dive at Breakwater.

November 9-11: Veteran’s Day weekend dives.

December 7: Club Holiday Party Dec 20-Jan 4: 6th Annual Cozumel Holi-day Trip.

For a complete listing of club activities visit Meetup or ATDC Event Calendar. See more details on page 5.

IN THIS ISSUE Entertainment Report ........................ 2 General & BOD Meeting Minutes .… 3-5 Arnie’s Tech Tibits, Pt 3 ……......… 6-9 Travel, Training, Events ................ 9-12 Club contacts & useful links ..…......…13

ACKNOWLEDGMENTS

Thank you presenters and newsletter con-tributors for making this Aqua Tooter possi-ble this month: Alan Throop, Gayle Hudson, Debbie Driggers, Jenn Pechacek, Arnie Warshawsky, Neil Benjamin, Kari Klaboe, Elaine Berger

Thanks to Steele’s Discount Scuba for sending member candidates to Aqua Tutus Diving Club. Steele’s is located at:

5987 Telegraph Avenue Oakland, CA 94609 (510) 655-4344

SEPTEMBER MEETING PROGRAM

At our September 5 General Meeting, our own Elaine Berger will present a program on Aquatic Medicine. This past spring, Elaine attended a confer-ence hosted by the International Society of Aquatic Medicine in Costa Ri-ca. She will be sharing some of the interesting things that she learned with the group, specifically about the effects of pressure on our bodies. Know-ing a few things about travel medicine can help us be better and safer di-vers.

Elaine has been diving since 2008 and her primary interest centers around her love of biology and marine life, particularly the echinoderms and the mollusks.

Please come and join us for this useful and interesting program.

Aquatic Medicine … becoming a better diver

Elections for the Board of Officers will be held at the November General Meeting. Please consider volunteering yourself or nominating someone that you have spoken with who might want to volunteer. We’ll have more information about the duties in the newsletter next month, but it only takes a few hours a month. It’s fun and gets you in-volved with the club and the general dive community in the Bay Area; it looks great on your resume; and it gives you a great sense of participation.

For now, please talk to any of the officers at the next meeting who have nametags or contact them at the emails in the newsletter if you have any questions.

The club is only as good as the people who participate in it.

Board elections are coming up !!

Help keep the club thriving and active !!


At our August general meeting, Neil Benjamin presented an entertaining and educational program on caves and caverns: what they are, where you find them, and how you can dive in them.

Neil started the presentation by describing the distinction between a cave and a cavern. A cave “is a hole in the ground or in the side of a mountain deep / twisty / far enough in to leave the light zone behind” and a cavern “is a name for a short or entrance part of a cave, still in light zone”.

With that primer complete, Neil took us through some fantas-tic photos of the different types of caves you can encounter: alpine, lava tubes, sea fracture, artificial, and solution caves.

Solution caves or karst caves were the focus of Neil’s presentation and he covered their gen-eral formation, with the Mexican Ceno-tes used as an ex-ample of karst cave systems that are frequented by scu-ba divers.

However, before you begin your cave diving adventure, proper training and

the appropriate equipment must be considered. Neil covered some of the basic navigation equipment that is used by cave divers, including continuous guidelines, permanent guide-lines, jump lines, primary reels, exploration reels, a com-pass, lights, and cave line markers.

The cave line markers were interesting in that the shape and orientation of some markers can be used by cave divers to convey additional information regarding the dive or diver. For example, the orientation of a cave arrow or REMM (both different types of cave line markers) can communicate the direction of travel of the scuba diver that placed the marker or can indicate the way out of the cave. This infor-mation is not only useful to the scuba diver that placed the marker, but is also useful to the other divers in their group and potentially divers that fol-low after the group.

Another useful tool to a cave diver is a “jump line”, which Neil explained is used when there is a break in the cave guideline that the scuba diver is using. This can be a potentially dangerous situation for a diver, as the they are without a guideline for a short portion of the dive. The jump line is a temporary line that is used to go from one guideline to another guideline. Neil demonstrat-ed how you would tie off your jump line to the cave guideline

ENTERTAINMENT REPORT (All photos credit: Neil Benjamin)

By Kari Klaboe

that you were leaving.

One of the most im-portant tools for a cave diver that Neil covered was the cave map. Significant work to de-velop vector maps of different cave systems has been performed by divers and Neil showed

a variety of maps that are available. Many of the maps looked like colorful scribbles, so it also likely takes a significant amount of practice to become proficient at reading these maps.

Neil ended the presentation with photos of his cave and cav-ern dives in the Yucatan, Mexico with Bill Briscoe and Ajna Cackovic.

He also showed videos of cave diving by Steve Bogaerts and HP Hartmann that are available on http://gosidemount.com/. Neil showed their vid-eo of the Glass Facto-ry dive in Abaco, Ba-hamas, but there are many amazing videos available in the video gallery (http://gosidemount.com/video/videoplay-er_GoSideMount.asp).

When asked what the appeal of cave and cavern diving was, Neil responded that it’s ex-tremely beautiful and the rock formations are spectacular. One only needs to watch the first few minutes of the Glass Factory video that Neil played to see this.

Thank you to Neil for presenting a wonderful primer on cave and cav-ern diving!

Also, thank you to Linda Phillips, Larry Dimitri, and the other Aqua Tu-tus club members that provided computer as-sistance during the meeting. The start of

the meeting was unfortunately delayed due to some challeng-ing computer issues involving a failed USB drive, but the group worked together to recover Neil’s presentation.

Credit: Wikipedia

Neil coming through the "tanks off re-striction" in the X-line in the Pet Ceme-tery section of NaHoch (Sac Aktun).

Points of light TajMeha Jan 2014.

Car wash side mount entrance

Ajna inspecting the Jaw's formation on the mainline in NaHoch Na Chich part of Sistema Sac Aktun, the white cave near

Tulum in the Yucatan, Mexico

Nariz

Dos Pisos


DATE: August 1, 2019

Meeting called to order by President Patti Shannon-Hocker at Rickys Sports Bar and Grill in San Leandro, CA at 7:31 pm. 33 members present. Speaker: Neil Benjamin, speaking about Cavern and Cave Diving Guests: • Hope - diving since ’88 started diving to overcome fear of

sharks

• Karla - in class with Jim has done one dive so far, looking forward to more

• Aaron- 20 dives, joining his father for the meeting

• Curtis - with SF Reef Divers since ‘78, cave diver

• Sal - three years diving with Jim, looking to do more diving

Treasurer’s Report (Helga Mahlmann) Club Assets, total: $5,746.05

• Classes = $2,478.21

• General account = $3,267.84

Entertainment (Jenn Pechacek) • September: Elaine Berger, Aquatic Medicine • October: Alison Young, Cal Academy – Citizen Scientists • November: Member’s Night #2, 2019 • December: No General Meeting; Holiday Party Dec 7.

Help with entertainment is always welcome , including taking notes of the presentation; recommending speakers; back-up for Alan to do set up. Any help is appreciated.

If you have any requests or suggestions for future entertain-ment, let us know at [email protected]

Membership and Meetup (Kat Smith) • Membership: 69 Regular, 9 Associate, 8 Lifetime - 86 total • MeetUp: about 88 members • Facebook: open to the public. If you post a dive there, any-

one can see it and potentially show up. • Meetup: Participation is limited to club members. If you want

to organize a dive, let Kat or an organizer know and she will make you a temporary organizer so you can set up a dive.

Training (Dennis Hocker) - See ads in this newsletter • AOW: Begins September 4 but it may be held earlier. Let

Dennis know by the August meeting if you want to sign up for the class. Prepayment is required to Dennis. Students must have 3-5 club dives prior to joining the class.

• Rescue Diver class: this September or October if enough interest (CPR and O2-Provider are required).

• If there is interest in any other training, let Dennis know. For more information on training, contact Dennis Hocker at 510-792-5606 [email protected] or Neil Benjamin at 510- 673-0073 [email protected] .

Newsletter (Alan Throop)

GENERAL MEMBERSHIP MEETING MINUTES August 2019

Reported by Debbie Driggers (for Secretary Gayle Hudson)

• Input is needed by the 20th of every month. • Contact Alan Throop at [email protected] if you are

not receiving the newsletter. Input due by the 20th of the month.

• Content on any material of diver interest is always welcome; dive reports and photos are encouraged.

Webmaster (Kari Klaboe) • The website up to date and current newsletter posted. • Content can be sent to [email protected]. Cencal: • No report. See semi-monthly reports in Tooter. Special Committees: • Holiday Party: December 7 at La Cabana. Party planning will

begin in August. The party starts at 6:30 pm and runs to about 11 pm. A committee will form soon and volunteers will be needed to help out.

Old Business • None

New Business

• We will do a group photo at the November meeting to be

hung at Ricky’s at the request of Ricky’s owners.

• Dave Chervin reports that Reef Check got approval for a cull-ing program of purple urchins. Reef Check will oversee and provide instruction, and monitor the results. This is not ur-chin genocide but an organized, measured effort. Reef Check certification is not required to participate, nor is a li-cense. Dives will be conducted at Lover’s in August and Sep-tember. Please contact Keith Rootsaert [email protected] if interested.

General / Announcements

• It’s never too soon to serve as a club officer. Please come to a BOD meeting and learn more.

• There was a discussion on moving to an earlier start time for general meetings. Concerns include getting out too late but also for commuters not being able to get here in time. It was also discussed to change the order of meeting segments; a lot of good suggestions. Discussion will continue at BOD and future meetings.

Dive reports • Larry the younger – talked about his extra week in Chuuk

and recommended that you research about the people you’re diving with so you know what sort of diving is available to you. After two weeks with the Tooters he was spoiled, noting that the next group demonstrated lots of crazy kicking and silting.

• DL and Matt – urchin removal: 1,000 pounds taken, lots of new people there but only the two Tooters.

• Larry the elder talked about the visit to the MBARI open house and the possibility of future presentations to the club.

• Linda P. and some other members joined one of Jim’s clas-ses. Fun dives but the dive along the wall resulted in a lot of fishing line.

(Continued on page 5 )


Date: August 15, 2019

Meeting called to order by Vice-President Devin Martinez-Shinn at Ricky’s Sports Theater and Grill in San Leandro, CA at 7:03 pm

Present: 11 members present. Treasurer’s Report (Helga Mahlmann) • Club Assets, total: $5,921.05

− Classes: $2,478.21 − General Fund: $3,442.84

Membership & Social Media (Kat Smith-absent) • Approximately 86 members.

• Meetup purge is in process. • Kari said she is missing some emails from members so can-

not send the newsletter to them via MailChimp and members should contact her if they are not receiving the newsletter.

Entertainment (DL Popplewell for Jenn Pechacek) Entertainment is fully booked for 2019. • September: Elaine Berger, Aquatic Injuries • October: Alison Young, Cal Academy, Citizen Science &

Tidepool photography. • November: 2019 Member’s Night #2 • December: No meeting; holiday party, December 7 Training (Dennis Hocker) • Advanced Open Water (AOW) class: Dennis and Neil will be

offering Advanced Open Water (AOW) class with the follow-ing schedule: Academics on September 12 & 17; diving on September 21 & 28; extra academics on September 24 if needed.

• Three students have paid their fees and others have ex-pressed interest. The cost for ATDC members is $150, due by the September 5 General meeting. The perquisite is three club dives.

If you have interest in these or any other training classes, please contact Dennis at: [email protected] . For more information on training contact Dennis Hocker at (510) 792-5606 [email protected] or Neil Benjamin at (510) 673-0073 [email protected]. Newsletter (Alan Throop, not present) • Alan will be out of the country September 3 through 23, so

there may be a delay in getting the newsletter out on time. • The annual Board elections are coming up and Patti will

send a description of duties for the next newsletter. Contact Alan at [email protected] if you are not re-ceiving the newsletter or to provide reports, photos, etc. Input is due by the 20th of the month. We’re always looking for input from members on dive reports, photos, dive safety, marine conservation, ecology/biology, re-search, local organizations, travel, etc to share.

Webmaster (Kari Klaboe) • Some Board members had trouble logging into our website

so Kari did some research which indicates our Inmotion Hosting could be vulnerable to hacking. Kari removed all extraneous usernames and only the Board members who actually need access now remain. Our usernames, for the

BOARD OF DIRECTORS MEETING MINUTES AUGUST 2019

Reported by Gayle Hudson, Secretary moment, are reasonably secure but she may change them in the future.

• Kari submitted the annual Inmotion website renewal to Hel-ga for payment by the end of August.

• Kari distributed a copy of an updated membership applica-tion, which she will post to the website. The new form shows “Step 1: Membership Application and Liability Re-lease,” followed by “Step 2: Pay Dues.” This should avoid confusion to new members as to when to pay their dues online.

• We’re always looking for content. Content can be sent to mailto:[email protected] .

Cencal • no report

Special Committees • The Holiday Party is scheduled for December 7. Advance

tickets are $10/members; $15/guests; and $3/child 10 yrs and under. Tickets sold at the door will cost $20/20/$5, re-spectively. Alan will be away for most of September so Kari offered to chair the Holiday Party. She will be asking mem-bers to volunteer for tasks.

Old Business • Distribution of Member Roster – tabled from the June Board

meeting: The question of how the member roster should be distributed to the membership was discussed. Kat has been approached by members asking their home addresses not be distributed to the general membership, including for some members, their phone numbers and/or email address-es.

• Kat proposed a radio button be added to the online member-ship application, wherein members can ‘opt in’ to have their specified information published. Discussion ensued. Gayle made a motion to add a radio button to the membership ap-plication, allowing members to opt in. Kari seconded and the motion passed.

• Cyberlink DVD: Helga reported the Cyberlink DVD software is not available through TechSoup. Larry the Elder will look elsewhere for pricing.

• Change in General Meeting Time – tabled from the July Board meeting: The Board discussed Dennis’ recent pro-posal to change the meeting time to 7 pm so the meetings can end by 9 pm. Devin repeated concerns made by mem-bers at the General meeting, including concerns about traffic delays. Discussion ensued, including compromising with a meeting time of 7:15 pm and moving topics around to ac-commodate latecomers. It was decided not to change the meeting time. Dennis asked we limit speakers to 35-40 minutes and decrease the amount of time for discussing past dives.

New Business • January General Meeting: It was decided to hold the Janu-

ary General meeting on the second Thursday, January 9. Ricky’s will be notified of the schedule change.

• Monterey Bay Aquarium Adult Sleepover: Kat heard about a 21 and over adult sleepover at Monterey Bay Aquarium (MBA) with 80’s music and a taco bar. However, tickets were sold out within 48 hours. The cost for this event is $95

(Continued on page 5 )


Not getting your club emails or Meet-UP notices?

Pay your 2019 membership dues so that you receive all the current information on Meet-Up and club emails.

Stay current with club activities ….

Annual membership dues can be paid at any club meeting to the Treasurer or Membership chair: $40/member, $10/associate, and $25/ student. Those joining after Oct 1, 2018 are considered paid through 2019. See benefits here. Dues can also be paid online at https://aquatutus.org/membership-application/

• Larry the younger was awarded the Gorilla Diver and Jono

the WAR diver and bonnet for their dives in Chuuk.

Bone Nominations

• None Good Buddy award

• None Upcoming Activity and Dives 2019 • August 24-25: Salt Point Club Dive weekend. Reservations

now open. POC is Debbie Driggers. See ad in this Tooter. • September 8 -10: VDM Channel Islands dive. Contact Alan

Throop or Bill Delameter. See ad in this Tooter. • September: Urchin Removal dive date and location TBA;

watch Meetup. • October 12: Club Dive is an (almost) Full Moon dive at Break-

water, 4:30 pm. POC is DL. • November 9-11: Club Dive Veterans Day Weekend, three

days of diving. The ninth will be Point Lobos; 10th and 11th locations TBA. Let Kat know if you’ll be attending as she is thinking of renting a house for the weekend. POC is Kat Smith.

• December 20-January 4: 16th Annual Cozumel Extravaganza. Patti will arrange hotels, contact her for space. Dive with Dive Paradise. $86 per room per night dbl occupancy or $82 for single in a room. Ten members have signed up and more are interested.

2020 • May 8-18: Maumere, Komodo, & Bima, Indonesia - Aboard

the Explorer Adventure Blue Manta. POC: Dennis Hocker. One space is left.

2021 • July 26—July 10: Bonaire with Dennis. See ad in this Tooter. Next Meetings • Aug 15: BOD Meeting

• September 5: General Meeting • September 19: BOD Meeting Meeting Adjourned: 9:29 pm

Upcoming Club Events !!

.. See Meetup or call POC for CURRENT information ..

• Sept 8-10: 3-day Channel Islands dive trip on live-aboard Vision; POC: Alan Throop. See ad.

• Sept Club dive: location TBD. POC is Kari Kalboe.

• October 12: Full Moon Club Dive at Breakwater; POC is DL Popplewell.

• November 9-11: Veteran’s Day Weekend dives, to in-clude Pt Lobos. POC is Kat Smith.

• December 7: Club Holiday Party at La Cabana. 6:30-11:00pm. Looking for folks to help; see ad in this newslet-ter.

• December 20—January 4: 6th Annual Cozumel Holiday Trip. Join us anytime during that period. Patti will arrange hotels; contact her for space. Cavern diving opportunities may also be available.

August General Meeting Report (cont.)

for MBA members and $150 for non-members. Kat called MBA to request additional dates and was told letters might help convince MBA to add more dates. Kat also mentioned our Aqua Tutus would be interested and asked if they do spe-cial events for groups. MBA indicated they do group events, for groups of 100. Kat is encouraging members to write a lot of letters to MBA requesting more sleepover dates.

• November Board Elections: Board elections will be held in November for President, Vice President, Secretary, Treasur-er, Membership Coordinator, and Director of Training. Enter-tainment and Webmaster are volunteer positions.

• Annual Board Retreat: Gayle asked if an annual Board re-treat will be held this year and it was decided not to schedule a retreat.

• Kat reminded Board members that, as part of their duties, they should be offering to POC dives so we always have a Monthly Club Dive.

Upcoming Activities • August 23-25: Club Dive Weekend – Salt Point

Campgrounds (reserve your spots!); POC, Debbie Driggers. • September 8-10: Channel Islands with Vaqueros Del Mar

Diving Club • September club dive: TBD. POC is Kari Klaboe. • October 12: Full Moon Club Dive at Breakwater; POC is DL

Popplewell. Helga will be scheduling a morning PG Chamber Tour

• November 9-11: Veteran’s Day Weekend to include Pt. Lo-bos; POC is Kat Smith

2020

• May 8-18: Maumere, Komodo, & Bima, Indonesia - Come aboard the Explorer Adventure Blue Manta. POC: Dennis Hocker. One space left.

• August, 2020: Club dive in Lake Tahoe; POC is DL Pop-plewell

2021 • July: Dennis is looking into a trip to Bonaire. Let him know if

you have any interest

Next Meetings

• Next General Membership meeting: September 5, 2019 • Next Board of Directors meeting: September 19, 2019.

Meeting Adjourned: 8:32 pm

August BOD Meeting Report (cont.)


Tech Tidbits… Episode 4

Flotation: BCDs and Wings

by Arnie Warshawsky (photos provided by Arnie)

(Editor’s note: Arnie has offered to write a series of articles on his experience with technical diving. Dennis has trained a num-ber of club members and others for this, and has opened up some wonderful experiences that combine both technical and recreational diving during his trips abroad.

Arnie is part of the Aqua Tutus contingent that now lives in Hawaii. Enjoy his perspective on this! )

In this article, the fourth in the series, I will talk about the de-velopment of buoyancy control devices (BCDs) and discuss some options for consideration by a budding technical diver. One of today’s basic training skills is to hover in the water col-umn; to do this you add just enough air into your BCD to get neutrally buoyant. Imagine how much more difficult this skill would be if you couldn’t add or release air from your BCD.

This was the situation for pioneering divers since BCDs had not yet been invented. During a dive, buoyancy normally fluc-tuated due to depth-related wetsuit compression and weight loss from continually exhaled gas from the cylinder. The only buoyancy adjustment early sport divers had was to drop the weight belt; a pretty crude option. Early divers had to muscle their way through it all. It was very difficult to hover in the wa-ter column because once you lost your forward motion you tended to drift either up or down.

Wetsuit compression and its effect on buoyancy are more significant in cold water like in Monterey, CA than in tropical water like in Hawaii. Of necessity, to dive in cold water you wear thick neoprene and must add enough weight to offset its significant buoyancy at the surface, but that initial buoyancy is progressively reduced with increasing depth due to wetsuit compression. Divers wear much less neoprene in tropical wa-ters, so buoyancy fluctuation due to wetsuit compression is nearly negligible.

Dive pioneers used experience (trial and error) to figure out how much weight they needed on their weight belts to be-come neutrally buoyant at various depths. The planned dive depth decided the correct amount of weight on their belts. Weight often had to be changed between dives. (This led to development of some very creative designs for lead weights to facilitate addition to or removal from the weight belt without having to completely undo it.) If a diver went deeper then planned, there was a risk of getting to a point where wetsuit compression left the diver so negatively buoyant that it became difficult to return to the surface. If fins and leg muscles were not enough and dropping the weight belt was still not enough, the diver had to shed what little remaining gear he had. Diving was a strenuous activity.

Tired at the end of a dive, divers sought ways to make life easier at the surface. Once again, war surplus gear came to the rescue. This time it was war surplus life jackets. Easy to slip on over the head and get positive buoyancy at the sur-face. Wearing one made it easier (and safer) to float on the surface and swim back to shore. War surplus Mae West life jackets (see figure 1) were exactly the same as the ones we see in airplane safety demos today. Because the jacket went over your head, it looked like a “horsecollar;” the nickname stuck. The horsecollar was secured with straps at the back that were brought around and clipped to a ring at the front. Life jackets had a tube to inflate orally and a CO2 cartridge to

auto-inflate. Actual-ly, the tube was the backup to the CO2 cartridge, but divers reversed the roles. There was no dump valve. Life jackets were only intended to be used at the surface. If you acti-vated the auto-inflate feature while underwater, you

would shoot up to the surface like a submarine-launched mis-sile - most likely incurring a serious air expansion injury.

By 1957, the US Navy was interested in mitigating the effect on buoyancy of weight loss from exhalation during an open circuit SCUBA dive. To do this, the US Navy Experimental Diving Unit (NEDU) designed and constructed “two compen-sators, one manually operated by the swimmer and the other automatically operated as a function of bottle pressure.” NEDU concluded that automatic systems were not worth pur-

suing but manual buoyancy compensators had meriti. Be-

tween diver experiences using Mae West vests and the 1957 NEDU study, manufacturers recognized a market, and they began producing what ultimately evolved into BCDs that we

( Continued on page 7 )

Figure 1 Two horsecollar life vests. Left: A war surplus Mae West life jacket. It has an oral inflation tube and a CO2 auto-inflator but no dump valve. (Photo credit: Alec Peirce Scuba.) Right: Early com-mercial improvement to the Mae West added a zipper down the front and relocated the auto-inflator. The cord at the bottom of the vest activates the CO2 auto-inflator; the mechanism and the car-tridge are inside a pocket. Life vests should only be inflated at the surface.

Figure 2. Early BCDs.

Left: Swimaster BCD; one of the first true BCDs. It has the more familiar corrugated hose at the shoulder to inflate and deflate the vest during a dive and an overpressure valve on the right front. The CO2 auto-inflator is located on the back; the activating cord is at the bottom left side. The power inflator hand piece is a Dacor aftermar-ket addition connected with a pipe clamp. (Photo credit: Alec Peirce Scuba.) Middle: A nearly identical offering by SeaQuest. Right: This early BCD is a La Spirotechnique product, but falls into the equipment category of a Fenzy vest. It has a small cylinder with a yoke on it. The built-in yoke allows you to transfill the bottle from your main cylinder before the dive. During a dive, the bottle’s valve is opened and shut to inflate the BCD. The corrugated hose is located on the right front, but with the two-hose regulators of the time, there was no interference with the regulator.


are all familiar with today. The Swimaster is considered by many to be the first true BCD (see figure 2).

“Control” is what distinguishes a BCD from a life jacket. A BCD gives you control over your buoyancy by letting you add air, and more importantly, release air during a dive. The Swi-master, and later competitors, retained the CO2 cartridge for emergencies at the surface. Because air added during a dive would expand significantly as the diver ascended, an over-pressure valve was added to prevent blowing up the bladder. Figure 2 also shows an example of an Adjustable Buoyancy Life Jacket, invented in 1961 by Maurice Fenzy. The Fenzy, as it was called, was quite popular at the time. The one shown in Figure 2 was made by La Spirotechnique. It came with a small air bottle with a yoke fitting, called a Fenzy bottle. The bottle was roughly the same size as today’s Spare Air™. It was held in a sleeve at the front bottom of the BCD. Its pur-pose was to replace oral inflation through a small diameter hose with compressed air inflation. Before the dive, the diver attached the yoke to the main cylinder and transfilled gas into the bottle. During the dive, the diver opened the Frenzy bottle valve to add air to the BCD and used the corrugated hose to dump air. (You might consider this system as the first power inflator.)

The 1970s saw a surge in BCD development. The horsecollar gave way first to jacket-like, then to true jacket styles. Scubapro patented the landmark stabilizer jacket in 1971 (a style still sold today). The “stab jacket” incorporated most of the features seen in today’s BCDs. One of the more innovative steps at the time was adding a tank clamp so that you could attach the cylinder to the BCD doing away with separate backpacks. The following year, Watergill introduced the AT PAC wing, which was the first wing-style BCD. With the proliferation of BCDs, in 1979 NEDU evaluated 14 commercially available BCDs (horsecollar, jacket, and back-mounted) and concluded that only five were suitable for US Navy use; the others were deemed to require too much

training for Navy requirementsii. Among other things, the

study assessed surface flotation attitude for an unconscious diver starting prone or upside down in the water column. NEDU noted that horsecollar styes “always float a diver face up in an emergency situation.”

At this point, BCD design was functionally complete. Manu-facturing techniques were improved and amenities were add-ed (eg, pockets, better straps and buckles, and velcro cum-merbunds). The Fenzy bottle for automatic inflation was dis-carded in favor of low-pressue inflation from the diver’s breathing cylinder. Designs evolved to integrate weights with the BCD; the first were vertical tubes along the sides that held a mixture of lead shot and marbles. The lead shot provided the weight, while marbles prevented the shot from shifting as the diver changed attitude in the water. This design was re-placed by weight pockets with open mesh bottoms or grom-mets sewn into the sides of the open bottoms. The diver laced the bottoms closed with plastic rods that, when with-drawn, allowed the weights simply to drop away. Modern weight pouches, retained by clips and Velcro, are more prac-tical and much easier to use.

Technical diving inspired development of back inflation BCDs, because back inflation permitted larger air cells than jackets thus could provide more lift. More lift was useful for technical divers who carried heavy gear. Back inflation did not come without controversy, mostly centering on how the two styles hold an unconscious diver’s head at the surface. Jacket pro-ponents claim back inflation BCDs push a diver’s face into the

Tech Tidbits (cont.) water, whereas jackets support the head face up like a life jacket. Back inflation enthusiasts disagreed. As noted earlier, independ-ent testing by the NEDU supported the jacket adherents’ claims (as long as the jacket had the added weight of an attached cylin-

deriii). (Note: I’ve used both and simply feel more comfortable us-

ing back inflation—mostly because I don’t like the feeling of the jacket’s wrap around bladder pressing tightly onto me.)

Frankly, today’s BCDs are marvelous. They are easy to don and doff, sport lots of pockets to hold things, and have enough D-rings to carry everything you want to bring on your dive. Most of the high-end models are suitable for technical diving. The key criterion for technical divers is stability in the water—minimizing twisting between the doubles and the BCD—which is mostly

related to the backpack built into the BCDiv

. Two other important criteria are available lift and the ability to attach deco/pony bottles.

Figure 3 shows two contemporary BCDs appropriate for technical diving; there are many more available. When shopping for one, test for comfort with at least one cylinder attached before you make your purchase decision; even better is to try out your favorite in a fresh water pool—most dive shops will take back a BCD used in a pool, but once you take the BCD into salt water, you own it. Subtleties such as the cut of shoulder straps, contouring for female divers, D-ring locations, pocket flap security (Velcro closure or zipper), and others should be considered.

In the last 15 years, a flurry of what I call “tech wannabe” BCDs flooded dive store racks. D-rings hanging everywhere and wide straps that made them look “tech,” but with inexpensive plastic backpacks and flimsy buckles. With any BCD, you get what the designer wanted. There’s not much you can do to tailor things. There is an alternative: create your own modular system with a backplate to securely hold the cylinder(s), a harness to hold the backplate onto you, and a bladder (commonly called a wing) sandwiched between the two to provide the desired lift. This basic setup can be tailored to your liking by adding pockets, pouches, and rings where you want them. It is fair to say that most tech-nical divers use a modular system.

Backplates: I make a distinction between a backpack and a backplate. Backpacks were around since the beginning of sport diving, possibly earlier. They gave divers a way to carry their cyl-inders on the dive and came in many designs, from simple webbed harnesses, to Hawaiian slings (very popular in their day), to plastic assemblies built into BCDs.

Backplates were similar in function, but specifically intended to hold double cylinders securely. According to diving lore, the first modern backplate was created in 1979 by cave diver Greg Flana-gan during the first NSS/CDS cave training course taught by div-ing legend Scheck Exley; the backplate was made from an alumi-num road sign. A backplate is simply a stamped piece of metal with slots and holes cut into it. Banded doubles are firmly at-tached to the plate using the bolts on the bands. The harness is threaded through slots on the plate. (Note: When you get your backplate, check the slots the webbing threads through to make

Figure 3. Con-temporary BCDs suitable for technical diving. Zeagle Ranger on the left and Aqua Lung Dimension on the right.



I shouldn’t have purchased my first wing: It was very nice, very expensive, had a dual-bladder system, and sported 95 pounds

of liftvi

— significant overkill for my needs. I have since ac-quired two more bladders: 45-lbs lift and 25-lbs lift. I use the smaller capacity one the most.

A case can be made for bladder redundancy. Since technical gear weighs so much, technical divers rarely use weight belts or pouches, which means there are none to ditch. Ask yourself, “If my bladder fails, can I swim back to the surface?” If the an-swer is, “no,” then you have two choices: use a dual bladder as insurance against one failing, or accept that you might have to ditch your gear. (I rig my stage bottles with carrying handles. If I had to ditch my gear, I would unclip my stage bottle and carry it with me by hand.) You can buy dual-bladder wings, which are simply two identical bladders inside a single covering. Or you can use two of your own bladders mounting them in a sandwich with one turned backwards and rotating the corrugat-ed hose at the shoulder.

This leads me to my last point about bladders: the power inflat-or. If the inflator sticks open, you can get positively buoyant really fast; maybe too fast to stop it by disconnecting the Low Pressure Inflator (LPI) hose and dumping air. Moreover, if you have dual bladders, at first it will not be obvious which of the two is actually inflating. I address this potential problem as part of my 10-foot bubble check. First, I make sure both inflators are functioning properly. Then I disconnect one. (Not at ran-dom. I always use the same bladder so that in an emergency, muscle memory knows which one holds the air.) After I estab-lish neutral buoyancy at my planned max depth, I disconnect the other inflator. If you are already neutrally buoyant, you won’t need to add air to the bladder until you reach the surface at which point you can either reconnect the LPI hose or orally inflate.

Retraction bands: Now we enter the realm of diving religion. Tech divers either believe in retraction bands or think they are the devil’s contraption. There are even sects that quibble about using many short bands versus a single long band. Retraction bands are elastomeric or silicone cords (usually 1/4-inch diam-eter) that a diver installs around the wing’s air cell. The primary purpose is to streamline large wings by applying tension across the air cell to keep partially inflated wings as compact as possible. When the bands compress the wings they also tend to eliminate air shifts that normally occur within the air cell when the diver changes body posture. Correctly tensioned, retraction bands typically compress the wings to a width less than the diver’s shoulders, thus streamlining the diver. The two sects I refer to above are the OMS and the Dive Rite crowds. OMS uses a set of individual short ties between two grommets on the outside of the wing and a corresponding grommet on the inside fabric. This provides (varying) tension along the pe-rimeter of the wing. Dive Rite uses a continuous spiral wrap

sure that all sharp edges have been burnished, otherwise the slots will quickly saw through your webbing.) The rigidity and extent of the plate stabilizes the rig. Backplates are manufac-tured from several materials, but aluminum and stainless steel are the most popular. The only meaningful difference between plates of these two metals is the plate’s weight, which is a fac-tor in determining your overall buoyancy. In addition to the slots for threading the harness, many backplates also have slots for cylinder straps so you can use the rig with a single cylinder. Most wings similarly have corresponding slots for cylinder straps, allowing you to thread the cylinder band(s) through the wing and the backplate (that is how I do my recreational diving). Barring that, you can purchase an adaptor that holds a single cylinder with cylinder straps and has mounting bolts (like those on banded doubles) to attach it to the plate.

When I first started technical diving, the band spacing was criti-cal (11-inches center-to-center between the mounting bolts) to

match up with the drilled holes in the platev. Now, many plates

come with three holes 3/4-inch to 1-inch apart drilled at the top and a slot for the lower bolt. This lets you adjust easily the height of the cylinders to your liking and is sufficiently forgiving if your bands aren’t exactly 11-inches apart. The multiple holes are somewhat analogous to sliding a BCD up or down on the cylinder to avoid hitting your head on the valves. Getting the proper adjustment you like is mostly by trial and error.

Harness systems: My harness is a single length of 2-inch wide nylon webbing threaded through slots in the plate and other things I want, like shoulder pads and D-rings. There is a single failure point: the waist buckle. Since I use a crotch strap to pre-vent the rig from riding up on me, I offset the buckle from the center to avoid the crotch strap loop. Admittedly, it takes a bit of time to adjust things to your liking, but once it is done, it never changes. Getting in or out can sometimes be a chore because the shoulder strap spacing is fixed—I duck down and slide up into the harness—but I can live with that. If you can’t, vendors offer deluxe harnesses. These mimic what is available on high-end BCDs. For example, buckles to open the shoulder straps, adjustable shoulder straps, sternum straps, rings, etc. Each clip and buckle adds another potential failure point. Be forewarned. On my tech diving rig, I strive to minimize failure points.

Bladders: They come in two basic shapes: doughnut and horseshoe. An unscientific survey of comments on various scu-

ba forums suggests that technical divers prefer the doughnut to the horseshoe. Bladders are available in various amounts of lift, so you can tailor your rig to what you need. Figure 4 shows several typical wings, as the bladders are known.

So how much lift do you really need? In general, you need enough lift so that you are neutrally buoyant at your maximum planned depth. The main factors are cylinder and backplate weight after accounting for buoyancy loss due to wetsuit com-pression at the planned maximum depth. Remember you don’t use the “air” weight, rather the net submerged weight.

Tech Tidbits (cont.)

Figure 4. Typical wings. Left to right: Halcyon Explorer horseshoe, Dive Rite Travel XT doughnut, and Dive System horseshoe.

Figure 5. Retraction bands. Left to right: OMS Trieste with single bands, Dive Rite Classic XT with a continuous band, Custom Divers TDB with a continuous band along the outer side of the wing.



>>> SUPPORT AQUA TUTUS DIVING CLUB <<<

Amazon donates 0.5% of the price of your eligible Amazon Smile purchases to our dive club. Just sign up for the club at www.smile.amazon.com

You just shop and our merchants give up to 5% back to our club !! Shop online, buy groceries, or dine out to support Aqua Tutus Diving Club … at no cost to you !! Just sign up at www.escrip.com

NOTE: SaveMart is no longer on the eScrip list

VOLUNTEERS NEEDED FOR THE HOLIDAY PARTY

Saturday, December 7 La Cabana Mexican Restaurant

7163 Rich Ave, Newark

Want to help this year? Committee work will begin in September; we have a number of small tasks where

we can use your help. No meetings; all work done by email... See Kari Klaboe .. Beginning now.

routed through tabs on the wing and the inside fabric. Be-cause it uses a single elastic cord, it tends to apply equal tension across the entire wing. (See figure 5.)

Arguments rage about which style is most appropriate for cave diving centering on minimizing the potential for snag-ging. I’ll leave that debate to others. I do want to point out one important caution. If you are installing retraction bands on the wing, be careful that the tension is not so much that it becomes too difficult to orally inflate the bladder during an emergency.

Next month: Regulators

ENDNOTES i Jensen, F.G., Searle, W.F., Jr., Research Report 8-57, “Buoyancy Control of Open Circuit Scuba,” US Navy Experi-mental Diving Unit, Washington Navy Yard, Washington DC, February 1957.

ii James R. Middleton, Report No. 1-80, “Evaluation of Commer-cially Available Buoyancy Compensators,” US Navy Experi-mental Diving Unit, Panama City, FL, March 1980.

iii ibid.

iv My Zeagle Tech BCD does not have a built-in backpack, which is one reason why this particular BCD is so comfortable. By itself, it is not stable enough to manage a set of doubles, but Zeagle (and others) sell a set of two small (about 1 inch by six inches) stabilizer plates that are mounted between the doubles and the BCD. The plates provide surprisingly good rigidity. Kind of a micro-backplate. Plus they only cost $20.

v Lamar Hires, founder of Dive Rite, claims responsibility for the 11-inch spa spacing. On the prototype Dive Rite plate—the first commercially produced—the person making the plate asked him where to locate the mounting holes. Hires said to drill the holes 1 inch from the top and the bottom. This gave us today’s standard 11-inch spacing.

vi Lift specifications for a dual bladder unit refers to one, not both, of the bladders. You don’t get more lift by trying to inflate both bladders because the cover limits the available volume.

The upcoming 17th Annual IOFF will take place on March 12 - 15, 2020 at Cowell Theater at Fort Mason Center for Arts & Culture, as well as other theaters within the Bay Ar-ea (and beyond!).

Save The Date & Submit your entry !

We're excited to begin a new season, with amazing films and

more opportunities to entertain, educate and empower audi-

ences of all ages to fulfill our mission: Saving our oceans … one film at a time!

See http://intloceanfilmfest.org/

See https://vimeopro.com/user21783508/every-nine-minutes Blue whales, the largest beings ever to grace our planet, can weigh up to 300,000 pounds ... the same amount of plastic enter-

ing our oceans every nine minutes. The Monterey Bay Aquari-um and Golden Gate National Recreation Area created a life-size traveling art installation, a blue whale sculpted from recy-cled plastic. Their objective: to reduce plastic use, while cele-brating this magnificent creature’s existence. Directors: DJ O’Neil & Oliver Hamilton (USA) - 5 min

Nation’s first Underwater Veteran’s Memorial opens to divers

The nation's first underwater memorial hon-oring America's veterans opened to divers in Clearwater, Florida, this week.

Located roughly 10 miles off the shore of Clearwater and at a depth of 40 feet, the Circle of Heroes memorial displays 12 life-size concrete statues representingthe men and women from the U.S. Army, Navy, Air Force, Marine Corps and Coast Guard. An additional 12 statues will be installed in 2020 to complete the 100’ memorial.

See: h�ps://abcnews.go.com/Poli�cs/

na�ons-underwater-veterans-memorial-

opens-divers-florida/story?id=64828212


Training & Growth Opportunities !!

If interested in training classes (First Aid, DPR, DAN O2 Provider, Enriched Air, Deep Air, other specialty), please Contact Director of Training, Dennis Hocker at

[email protected]

• For more information on training, contact Dennis Hocker at (510)792-5606 [email protected] or Neil Benjamin at (510)673-0073 [email protected] .

Upcoming Diver Training

Club members are always welcome & encouraged to attend any classes or dives.

• There is potential interest in a skin diving class on the North Coast. Contact Dennis if interest-ed.

• An Advanced Open Water (AOW) is being held in September. Must do 3-5 club dives prior to class. See ad in this Tooter. Contact Dennis if interested.

• Rescue Diver class will be held after AOW class if there is interest. CPR and O2 provider re-quired. Cost to club members will be $150. See Dennis.

PADI Advanced Open Water Certification class

Dennis & Neil will be offering an Advanced Open Water (AOW) certification class this Fall. The current class schedule is:

• Thursday Sep 12 academics 7 – 10pm • Tuesday Sep 17 academics 7 – 10pm • Saturday Sep 21 class dives • Saturday Sep 28 class dives • Tuesday Sep 24 academics make up if needed

Cost for club members: $150 for manual and certification fee. Cost for non-members: $225. Due by Sept 5 General Meet-ing. A prerequisite is to have completed 3-5 club dives prior to the class. If you are interested, please contact Dennis Hocker at (510)792-5606 [email protected] or Neil Benjamin at (510)673-0073 [email protected] .

Upcoming Open Water Classes

Available from “Original Steele’s” Dive Shop

5 week class Tuesday & Wednesday nights, 14 hours in a pool, 5 dives in Monterey… a class that trains you for diving in more-challenging California coastline. Divers say if you can dive here, you can dive anywhere in the world !

Upcoming OW classes for Aug & Sept are:

• Classroom: Aug 13 & 14 • Pool: Aug 20 & 21, 27 & 28, Sept 3 & 4 • Pool test: Sept 10; Written test: Sept 11 • Checkout Dives: Sept 15 & 22

5987 Telegraph Ave, Oakland, CA 94609 510-655-4344

“Jim wants to train competent di-vers who will become a part of the local dive community” … YELP

Latest news from Sharks Stewards

See: h�ps://mailchi.mp/sharkstewards/shark-week

-1094929?e=d28274c9b6

Events and Volunteer Opportunities September 15, 22, 29 and through November Farallon Island Ex-peditions Book at: h�ps://sharkstewards.org/event/farallon-expedi�ons-2019/

September 27 Sharks and Sanctuary Photographic exhibi�on launch at Canessa Gallery, San Francisco. Original art-

work of sharks and protected areas September 28 Sharktoberfest at the Sanctuary Family shark fun at the Greater Farallones Na�onal marine Sanctuary HQ, Crissy

Field. 11AM - 4 PM . VOLUNTEER!!

October 3 Sharktoberfest California Academy of Sciences Launch of documentary Hidden Pacific, panel discussion, shark science and fun 6

-10 PM

October 7-13 Guadalupe Island White Shark Expedition

Exclusive trip led by Shark Stewards Tickets Available


Sign-up NOW !! Full boat, but short waiting list is available

CHANNEL ISLANDS LIVE-AOARD DIVE TRIP

SEPTEMBER 8 - 10, 2019

Join Vaqueros Del Mar Dive Club and other Toot-ers for three days of fun diving the Channel Islands aboard Truth Aquatics’ 80’ flagship Vision.

A great short vacation and way to experience live-aboard diving in our beauti-ful west-coast ocean.

Send check (payable to “VDM”) to

Bill Delameter 864 Alden Lane, Livermore, CA 94550

(or give to Alan at meeting)

Questions? $Bill Delameter, VDM [email protected] 925-455-6834 … or

Alan Throop, Aqua Tutus [email protected] 925-577-7876

• Limited load (< 32 divers; capacity 46 divers)

• Kelp Forests, So. Cal marine species • Fall conditions… warm(er) water • Great food, crew, & dive buddies • Nitrox available (O2-clean tanks NOT required)

• Northern or Southern Islands TBD

• $600 per diver (non-diver: 10% discount)

Interested in dive travel ?

… let us know !! Folks in the club are planning some interesting dive trips in the near future and need to hear from you if you might be interested. Dennis is planning a dive trip to Bonaire in 2021… a premiere Caribbean dive destination … easy diving, a marine sanctuary since 1972, so great marine life, and many topside activities. Contact Dennis if you are inter-ested at [email protected] . See www.infobonaire.com/scuba-diving

(photos: Bonaire website)

DIVE INDONESIA in 2020 !!

May 8-18, 2020

Maumere-Komodo-Bima … and visit the Drag-ons of Komodo …

On board the Explorer Ventures Blue Manta : https://www.explorerventures.com/indonesia-liveaboard-

diving/blue-manta-explorer-komodo-itinerary/

Package price $4,700 (based on payment by check)

• 10 nights twin share accommodations

• 9 ½ days of diving

• meals & snacks, park fees,

• Port & Hotel taxes and transfers.

Airfare to Maumere (MOP) or from Bima (BMU) is extra. Space is limited to 12. Booking deposit $1,000. As always will be filled on an as-deposit-received basis.

There will be an option to add some pre trip / post trip extra days of Land Based Diving.

For more information contact Dennis via email [email protected] or 510-RxSCUBA (797-2822 ).


Club meeting dates for 2019

General Meetings Board of Directors Meeting

(typically 1st Thursday) (Typically 3rd Thursday) (*not 1st Thursday)

September 5 September 19

October 3 October 17

November 7 November 21

December … No meetings. Holiday Party, December 7

The club needs your help!

Join our Entertainment Committee and help by oc-casionally writing reports for the Tooter, controlling the laptop during programs, contacting interesting peo-ple, or in other ways that suit your interests. No long-term commitment required and a great way to get in-volved and help the club. Interested? Contact Jenn Pechacek at [email protected].

Support Reef Check

Sunday, September 15, 12:30-2:30 pm

Each year, more citizen scientists join Reef Check. We’d like to invite you to bring your family and friends and learn about who we are, what we do, where we work and why we do it.

A fantastic friend of the ocean, Louie Psihoyos created a must see film: Racing Extinction.

Let’s gather to celebrate the fact that each year, Reef Check is growing and succeeding at our goal of saving reefs worldwide!

Questions?: See Dave Chervin at the September Gen-eral meeting OR at [email protected] . MOVIE STARTS PROMPTLY AT 12:45 P.M. Donation is $15. To purchase tickets us this link: www.reefcheck.org/screening

Exposing the hidden world of wildlife crime

“Infiltrating the world’s most dangerous black markets,

a covert team unmasks the dark world of wildlife traf-

ficking, a lucrative and organized enterprise with links

to criminal syndicates. Using high-tech tactics, OPS

reveals never-before-seen images that will forever

change the way we see the world, bringing a voice to

the thousands of species teetering on the brink of sur-

vival. The world is singing, are you listening?”

Racing Extinction

… the movie

We are Racing Extinction, and we cannot afford to lose! See the trailer at:

https://www.opsociety.org/our-work/films/racing-extinction/?gclid=Cj0KCQjwwIPrBRCJARIsAFlVT8-kVb0QB6g-GYiEU6vHUBKAmYQHaGBJf4zvrns2O6SWDHBBWZx1TAiwaAiswEALw_wcB


BIG ISLAND, HAWAII

KONA CONDO FOR RENT

Book now at this low price!

June 29 - July 13, 2019

$500 per week + $14 tax One-time $50 registry fee covers one or all weeks. Weeks run Satur-day to Saturday.

Contact Don Kel-sey 925-820-8362

[email protected]

» Resort info can be found on The Kona Billfisher website.

Internet Resources for the Bay Area Diver http://www.garlic.com/~triblet/swell/

Monterey Bay National Marine Sanctuary https://montereybay.noaa.gov/ https://www.facebook.com/MBNMS

Monterey Bay Aquarium Research Institute http://www.mbari.org/ https://www.facebook.com/MBARInews?fref=ts

California Marine Sanctuary Foundation http://californiamsf.org/index.html

Pacific Grove Hyperbaric Chamber https://www.facebook.com/PGHyperbaricChamber http://californiamsf.org/pages/donate-pgh.html

2019 CLUB OFFICERS & CHAIRPERSONS

President

Patti Shannon-Hocker ….…………[email protected]

Vice-President

Devin Martinez ………..……. [email protected]

Secretary

Gayle Hudson …………….……… [email protected]

Treasurer

Helga Mahlmann…………...………[email protected]

Membership Coordinator

Kat Smith ………...……….…… [email protected]

Director of Training

Dennis Hocker ………………......…. [email protected]

Entertainment Coordinator

Jenn Pechacek …….…..… [email protected]

Newsletter Editor

Alan Throop ……………….…. .…[email protected]

Social Media Coordinator

Gayle Hudson……………… .…[email protected]

Board Members at Large (BML) , July’19-July’20

Angela Boultinghouse ………..……..…[email protected]

Chuck Harlins …………………… ……[email protected]

“DL” Debra Popplewell … …………...…[email protected]

Webmaster

Kari Klaboe ………….……...…. [email protected]

Past President

Kari Klaboe ……………...…. [email protected]

SUBMISSIONS TO NEWSLETTER &

WEBSITE NEEDED

Dive pictures, videos, reports, article, stories, envi-

ronmental, and all things diving- and marine-related

are needed for the website, the Tooter newsletter,

YouTube, and social media sites. Visit our photo

submissions page, send to the club contacts listed

above, OR send to [email protected] .

NEWSLETTER PUBLICATION SCHEDULE

Submissions for the “Tooter”, both web- and

emailed/pdf-newsletters, are due by the 20th of each

month. The Tooter is published by the end of the

month. No publications in December.

Documents

Since 1955; now in our 64th year of diving safety & fun ... · 8/8/2019 · was the cave map. Significant work to de-velop vector maps of different cave systems ... 2014. Car wash