In 2016 I obtained the report of one of the Mine Safety Appliance's Project (MSA) mangers reports on the PLUS OR MINUS 25% accuracy of the MSA. It did not come close in meeting the OSHA requirements for our safety even at the .5ppm Permissible exposure level (PEL). CO-MANAGER OF THE MSA TOXIC VAPOR DETECTION UNIT FOR THE TITAN II NUCLEAR MISSILE SILO'S ADMITS SOME FACTS IN 1964.
Email from Dan on MSA calibration and sensitivity topic (back in about 2010).
Terry’s note: This conversation validates that the OSHA exposure requirement of 0 .5 ppm for a eight hour time weighted average(TWA) permissible exposure limit (PEL), that was in the Dash One Manual, was not conformed to at all by the Air Force. I want to point out that the MSA was never checked with known amounts of fuels less than 10 PPM. Again, this confirms that the .5 PPM was never complied with by the Air Force.
After graduating college with a BS in Mechanical Engineering I worked for a major missile systems manufacturer and designed defense missile test equipment based on a safety factor of 5. This means that the MSA missile fuel vapor detection system should have been calibrated and tested at .1 ppm if the USAF was concerned with our safety. The three standard deviation method of building test equipment required by military contracts or electrical components/gauges/errors of any component of the MSA equipment should have been implemented so the .1 ppm calibration would have been a reliable accuracy to 99.9%. The Titan II MSA UDMH detection system failed both criteria miserably. So, how much were we really exposed to? I believe much more based on the 1983 DM Titan II complex study (which was also flawed). Click here to see how DM Bioengineering failed to use the right OSHA equation for the short sampling time they used in the launch control center (LCC).
QUESTION 4 AT THE BOTTOM OF THE PAGE VERIFIES THE USAF DID NOT CARE ABOUT OUR SAFETY AT ALL.
4. I guess I am surprised that after the calibration they didn't have an Ampoule with 0.5 ppm/ 4 cu ft bag worth of UDMH that you checked to
see if the system would meet the TLV-TWA requirement of our Dash 1? I guess I shouldn't be surprised as the guys I emailed a couple years ago that
worked at MSA laughed when I said the TLV-TWA for 8 hrs was 0.5ppm for UDMH and that I assumed we calibrated for that amount. We did not even meet that requirement from OSHA, for monitoring exposure, at that time. Boy, we were young and stupid as you said.
Yup, never worried under 5 PPM, and never actually calibrated under 10 PPM -- well, except zero, but that could easily have been more or less, since the unit really couldn't read it under 1 PPM. We were led to believe that anything under 10 PPM wasn't bad for you, and anything over 40 PPM should be avoided. If the MSA read a leak on the missile (say on level 5 to 8 as she cycled) you could bet that on the
missile it was in the 10,000 PPM range, as the pick-ups were on the wall. So, a 10 PPM on the wall was a really big leak!
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Dan (MSA calibration tech) EMAIL:
I calibrated the MSA's at Little Rock sites from '75 to '79 (E-Lab, Guidance and Control shop, MIMS). I found the units to be very accurate and never
had any real problems with them. But, they were temperamental (no real pun intended) in that the LIRA needed to reach and maintain a consistent
temperature before she became stable. We sampled air from each one of the silo levels (rocket side), to include the level 9 pump rooms (UDMH and
N2O4). I know they changed the daily tolerance of both, downward over time, but while I was working on the equipment we calibrated to 10 PPM and 40 PPM.
The LIRA was only utilized for a massive leak of N2O4 to operate the water deluge system, since the N2O4 was capable of self-ignition.
The reactants utilized were trifluoric acid and anhydrous ammonia which were mixed with a know amount of air and passed through the ion chamber utilizing either
Americium or Radium. The ion chambers hardly ever gave us a hard time, and they tended to last about 4 years each on the average before the Americium
or Radium had to be replaced (due to the caustic reactants utilized).
The MSA was very stable as long as the reactant levels were sufficient. To maintain the systems, we had 30 day, 60 day, 180 day and 360 day inspections
and calibrations (periodic maintenance). Since we had 18 sites, that meant we basically did one site a day, but depending on how far the sites were
from each other, and such, we could do a couple if needed on the same day.
Most of the time, when a system went down, it was due to running out of reactant - not an electronic or mechanical problem. There were check-valves
on both units that would regulate the incoming air, and would also ensure no reactants traveled back down the air pickups (no backflow). These had
Teflon balls and were changed out with new ones about every 6 months. They were supposed to last about 8 months, but sometimes would fail at about 4 to
6, and they could take the site off-line (UDMH or N2O4) so the site would go red. We normally fixed these within a day of going 'red'. Also, the
reactant would run out now and again too. We could normally tell the check valves were wearing out due to the reactant consumed. If noticed, we would
change out the check valves early so the system would not fail.
We calibrated the units at 10 PPM and 40 PPM each month on the 30 day checks. We had ampoules of UDMH and N2O4 that we broke into bags and then filled the
bags with air. They took about 4 cubic feet of air. We would then allow the unit to sample the air in the bag and calibrate the gauges to 0, 10 & 40
PPM. Once finished, we would dump the remaining UDMH and/or N2O4 into atmosphere (stupid, but we were young). If the meters read true, then the
entire 30 day inspection took about an hour. If not, you had to take the unit off line, fix the particular problem - normally a unit that measured
the density of the ion chamber - re-calibrate and then let the unit warm up for about an hour (since you didn't want any swinging of the meters and
sounding of alarms). The re-calibration would take about 4 to 5 hours on-site.
I built a piece of test equipment that mimicked the ion chamber to pre-calibrate the units at the lab on-base, and that saved us about 2.5
hours on site if we had a pre-calibrated one. However, you still needed to run the checks on site, and sometimes even the pre-calibrated ones needed
re-calibration in the units - probably got rattled in the kit going from site to site.
I noticed the MSA panel on your website was showing about 2 PPM on the Fuel and Oxidizer side, and negative on the LIRA. Of course, that would not be
right. That was just a slave unit from the MSA on equipment level 6 and the meters would read the same. Alarms would sound at 5 PPM, and the units
normally read zero. I've seen one of the 3 slave meters go bad, but never all three. -- but I've also seen much of the same when entering the sites.
The small black screw at the bottom of the meter would move the indicator about +/- 3 PPM, and could also drive the LIRA about the same. We would
make sure they were all zero after calibration, as sometimes they would show a PPM or so (when really not sampling anything at all). So, I'm inclined to
believe that the picture was taken by a crew member after tweaking the meters (for the picture) or it was taken from the museum site at DM (where
there is minimum maintenance anymore).
Also, I do know there were some sites (at all three bases) where the MSA tended to be more problematic. I, and my teams at LRAFB, worked hard to keep them on-line and calibrated, but I know from fact that some at MAFB and DMAFB flights were not as diligent.
So, you would have crew members who were always glad you came to 'fix' their MSA and bring their sites 'green', but they would also remember the 3 or 4
days the site was 'red' due to my broken MSA for the next year, and they would let you know about it, for sure. We had a good relationship at LRAFB
and tried our darnest to keep the sites green.
I remember them talking about going to 1 PPM as the tolerance, but it was not so when I was working on the sites. So, finding 69 PPB on site must
have been much later than when I was there. Also, the reactants could/would give false positives, so that should have been taken into account. Each LCC
had at least 2 portable Vapor Detectors (PVD's) that were used to enter the launch duct if the MSA was red (broken for some reason or another). These
were stored in the LCC and could easily have been the cause for finding very low concentrates of UDMH or N2O4 residue. The reason the sampling at level
6 of the equipment area was higher than normal was because that is where the MSA was and where we dumped the excess from the calibration bags. Since the
MSA did not sample the equipment area (except level 9 of the pump rooms) there was no effect on the readings to do so. Oh, the PVD's also were
calibrated at 0, 10 & 40 PPM - and nothing we had at the time would verify anything lower than 1 PPM - as if it was less than that, it was just zero.
Also, technically, the positive LCC pressure was utilized for 2 reasons. One, as noted to keep the air traveling from topside, to the LCC, to the
cableway and then through the equipment area to topside again (pretty far apart on intake to exhaust - maybe 500 feet or so). Two, was to ensure the
blast valves would operate if there was an over pressure (oops, like a nuke or something in the area) to protect the crew and rocket. I suppose
technically there was a third too, in that the launch duct had to be kept cool, as the UDMH and N2O4 would boil at about 78 degrees - so it was always
kept cold and with a slight wind to flush the air.
Let me know if you need anything else, or if this makes sense from what you have heard in the past. There was lots of stuff that was harmful in the
sites, both in the LCC and launch duct. Downstairs in the LCC you had a couple battery power supplies that would take up the equipment load when you
lost power (until the generator came on). These were Nicad and would be on charge when not in use. (air traveled from topside, downstairs, to level 2
of the LCC (where the crew launch functions were, to the cableway). Also, a lot of old electronics everywhere for EMP protection and such that utilized
PCP's.
I'll review the medical form and forward it back later today. BTW, I still work with the rockets here at the -------(DELETED), having been a Minuteman II ILCS
commander, then into Titan IV and now the Shuttle, Delta IV and Atlas V programs. I don't have a lot of faith in the medical aspects though, as
even though I had melanoma (and am still living to tell) I received zero disability when I retired from the USAF after 27.5 years. I think they are
pre-disposed to ignore the long-term effects of handling 40 PPM almost every day of both UDMH and N2O4 for a 4 year period, and any of the PCB's that
were in both the Titan II and Minuteman II LCC's. But, maybe that's just my opinion.
Terry:
Honestly, I never left site without a fully 'green' MSA (100% confidence that 0, 10 & 40 PPM were absolutely correct. If not, then I left the site 'red' till I got the parts I needed to fix the unit. I know there was some sloppy calibration on some stuff, but I never, never, never fudged on the MSA or on the Guidance. Later in 1978, they went to rivet-hawk modifications on the guidance, vies ours on manual input, because the powers that be thought that a 'reasonable' (MRT) guidance was better than a set of coordinates a couple of enlisted folks put in, but I also guarantee that the settings I and my buddies put in at LRAFB were way closer to the new computer generated guidance being updated. If you cared, you could get it within 25 feet, just as with the MSA, if you cared, you could ensure that it was +/- 1 PPM of actual (at 10 PPM, added by Terry). We cared -- and I'm not just stating that because I was in-charge, but because it was important to us to be both safe and accurate. I carried that over to my officer years (acting chief of Range Safety for Patrick AFB and Cape Canaveral for over 50 launches) and my current job launching rockets from the cape and Vandenberg. Blacked out as it references his government job title now.
Honest - +/- 1 PPM was our tolerance (at 10 PPM, added by Terry), and that was as close as we could get an accurate reading. I know this might not be what you want to hear, and I can't vouch for all, but it is the truth for my short time at LRAFB. I also did the Mass Spec ops during missile recycles, and my tolerances for those was 3 times 10 to the negative tenth (counting atoms coming through the seals). Unfortunately, there were good troops (officer and enlisted) and poor troops (same/same) that didn't worry about others safety, but I and my crew were always aware and pro-active - even for a bunch of kids (20 to 25 year olds). We thought it was important, so we made sure we did good work. Of the 32 guys (and one girl) in E-Lab at the time, over 1/2 of us finished our engineering degrees, and 4 of us became Officers in the USAF -- a pretty high upward trend for any enlisted (or other) military office!
TERRY ASKING QUESTIONS:
Let me ask you these questions:
1. The ampoules gave you the10 ppm by breaking it in a bag and then filling the bag with air from some source until the bag was inflated but not
broken to get the 4 cu ft?
Yes, we used the launch duct air coming into the MSA. Just disconnected the line, filled the bag and re-connected the line
to the MSA. The ampoule (glass insert) was in a soft plastic tube open on both ends that you cracked to let the gas out.
2. Then you let the unit suck the whole volume and adjusted the meters to read that amount?
Ah, sort of. We only used what was needed to verify the units read correctly. If we needed to do calibration, then sometimes we
used multiple bags of 10 and 40 PPM. Usually, the meters read right at 10 and 40. They were very accurate if the TFL and Ammonia was filled and the
system was clean. Generally, if they didn't read correctly, it was the reagent lines and systems - including the ion chamber - that were at fault,
not the electronics and/or meters themselves. Easy to trouble shoot, but time consuming to clean and fix and adjust if you wanted to be diligent and
have a good MSA for the next 30 days.
3. Was the mixture that homogenous after filling the bag?
Yes, mixed very well. The ampoules were gas, not liquid, and mixed evenly with the air to make a 10 PPM or 40 PPM sample.
4. I guess I am surprised that after the calibration they didn't have an Ampoule with 0.5 ppm/ 4 cu ft bag worth of UDMH that you checked to
see if the system would meet the TLV-TWA requirement of our Dash 1? I guess I shouldn't be surprised as the guys I emailed a couple years ago that
worked at MSA laughed when I said the TLV-TWA for 8 hrs was 0.5ppm for UDMH and that I assumed we calibrated for that amount. We did not even meet that
requirement from OSHA, for monitoring exposure, at that time. Boy, we were young and stupid as you said.
Yup, never worried under 5 PPM, and never actually calibrated under 10 PPM -- well, except zero, but that could easily have been more or less, since the unit really couldn't read it under 1 PPM. We were led to believe that anything under 10 PPM wasn't bad for you, and anything over 40 PPM should be avoided. If the MSA read a leak on the missile (say on level 5 to 8 as she cycled) you could bet that on the missile it was in the 10,000 PPM range, as the pick-ups were on the wall. So, a 10 PPM on the wall was a really big leak!
------------------------------End of Dan’s emails-----------------------------------------------------
Another email about MSA equipment from a PTS fellow.
Hello, I am a retired USAF veteran who served in the Titan II program for approximately 15 years in PTS. (some years were teaching at the PTS technical training school, Air Training Command) I am 58 years old and in reasonably good health.
I have personally witnessed fogs of fuel vapors in the silo and pump room that did not get a detection on the MSA equipment, although it was very reliable detecting even small releases of oxidizer.
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