Bulletin 1 0 5 DEPARTMENT OF THE INTERIOR RA KL K . LA E S E C R E T A R Y F N IN N , BUREAU OF MI N ES V A N . H . M A G D I R E C T OR NNIN . BLAC K DAMP IN MINES L E G . A . B URRE L, 1 . w. ROB RTSON AND G . G . OB ERFELL W AS HING TON G OV ERNM ENT PRINTING OFFICE 1 91 6 The B ureau of Min es in car in out one of the o isions of its or anic a — , ry g pr v g ct to b disseminate inform ation concerning investigations m ade prints a limited free edition li a ns o f each of its pub c tio . When this edition is exh auste co ies m a be o taine at cost rice onl thr o d , p y b d p y ugh m in in W hin n the Su e inten ent of Docum ents Gove n ent t O ce as to D . p r d , r Pr g ffi , g , C Th in n n f D um ents not an O iC’ia l o th Bu au o M e Super te de t o oc 133 fl f e re f ines . n l an h h ul ba d e an e tire y separate office d e s o d e d r ess d : E I TE D E T OF D O M E T SUP R N N N C U N S , Government P intin O ce r g fi , Wash n to D i g n, . C . Th n al la unde hi h blications are ist i u te ohi its the i in of e ge er w r w c pu d r b d pr b g v g n n Th os f hi u li ation is m ore than one copy of a publication to o e perso . e c t o t s p b c 1 0 cents . 1 91 6 . C O N T E N T S . I ntroduction Com parison o fatm ospheric air with mi ne air Composition ofthe atm osphere Transfer o f oxygen and carbon di oxide in breathing Effects on m an o fvariations in composition and am ount ofair Effect o f carbon dio xide Effect o fdiminished o xygen s upply . Effect of air at high altitu des E ct o fbreathin a ec eas in ox en su l ffe g d r g yg pp y Effect of a mi ne atm osphere low in o xygen Effect o f atm ospheres low in oxygen on canaries and mice General com m ents on tests Effects o f o xygen deficiency as showing relative value of birds and mice in explo ring mines Effect o ftemperature and m oisture on m an ila ion o fbuildin s a o e roun . Vent t g b v g d Ventilation conditions in mines Action of oxygen on coal i n at of abso tion of o x l I nflu nc of m o sture o e en bcoa e e r rp yg y f x n an d o uction of ca bon dioxid Abso tion o o e e om atm os h rp yg pr d r fr p eric air bwood y Discus sion of r esults E ect o f lowe in ox en and ai si n car on dioxide content on ex losibilit ff r g yg r g b p y o fm ethane-air mi xtures m i n o f o x n and oduction o f carbon i xi ons u t o e o de bm en and b C p yg pr d y y Foulin ofmin e air beca oftim e g y d y b r i i f la Specific gravity and compos t on o b ck damp . E ct on li hts of air low in ox en and hi h in ca bon di xi ffe g yg g r o de Effect of atm ospheres low in o xygen on fires in mines l f l - m Results of ana yses o coa mine at ospheres . Results o fanalyses o fsam ples in series 1 Comm ent on analyses o fsamples in series 1 Tem perature and humidity R l f anal f am l i esu ts o yses o s p es in ser es 2 to 6 . Comm ent on r esults of sam pling and analysis Sam ples in s eries 2 Sam ples in se ries 3 Sam pl es in series 4 Sam ples inseries 5 Samples in series 6 Effects o ftem perature and humidity and othe r factors E ects o flea a e of air throu h oors rattices tc ff k g g d , b , e I nflamma ble as in mines g TE TS 4 CON N . Occurrence and composition o f gas in r oc k strata o f the Cripple Creek gold minin dis t ict olo ado g r , C r Origin o fthe strata gas ts o fba om et ic ressure on outflow o f st ata as . Effec r r p r g Collection ofsampl es ofgas in four m etal mines Observations on gas in Midget mine . l ations a din aseous conditions in Ana n mi n a obse e co da ne . Ge er rv r g r g g Observations on gas in Cresson mine Tabulated data Special air samples from Mary McKinney mi ne i i n o f st ata as sam les c al culated on air- ee basis Compos t o r g p fr Effect on m en o fpartial pr essures o f o xyg n th indi ations af o d d ban l n l m a ison betwee e c e c e a d bacet n Co p r f r y d y y e e flam e and analyses ofthe sam pl es m us tibl e as i n the rock~s trata as Co b g g n tions o f 1 5 m tal mines as indicate banal ses o f air sam Ventilation co di e d y y pl es Observations r egarding black damp in c ertain m etal mines Summ ary . mthod f al 1 n ublications on mine accidents and e s o co m1 n P g I ndex B L A C K D A M P I N M I N E S . R B ER S A D B E A RELL . T O E B Y . UR . N . R LL G B , I W O ON, G G F . R D U INT O CTION . u i in n The B reau of M nes , pursuing investigations looki g to greater in i f safety min ng , has analyzed samples of the air in many di ferent U coal mines in the nited States , and has studied the analyses . This report presents the results of one phase of this study and shows how a tmospheric air, after entering a coal mine , loses oxygen and gains s o — l carbon dioxide with resulting formation of cal ed black damp . Also the report discusses the effects of the constituents of black damp n and on men , on the bur ing of oil and acetylene lamps , on the ex los ibilit . p y of methane The term “ black damp was and still is widely used to designate di fi accumulations of carbon oxide , but a more exact de nition of black E s ha s damp , as Haldane , the ngli h physiologist , pointed out, is an accum ul ation of carbon dioxide and nitrogen in proportions larger r i than those found in atmospheric air . The reasons for prefe r ng Hal ’ dane s definition are given on succeeding pages . C R S S HE R C A I R WI H E A IR OMPA I ON OF ATMO P I T MIN . h a a ir i W en tmospheric enters a coal m ne , it changes in composition according to ( 1 ) the velocity with which it traverses the workings ; 2 n i in — is ( ) the amou t of coal w th which it comes contact that , the extent of the mine workings that it tra verses ; (3 ) the gaseous nature o f the seam ; (4) the tendency of the coal to absorb oxygen ; and (5 ) n the temperature and wetness of the mi e . n fol As regards the details mentioned , the governi g conditions are as : 1 i lows ( ) Other th ngs being equal , more carbon dioxide and methane are present and there is a greater deficiency of oxygen at places where air l i . 2 The the is sti l, as at working faces and in old work ngs ( ) purity air d in l of the epends on the distance it has traveled , so that a wel ventilated mine the air is purer at working faces near the shaft than il at those that are remote . In the same mine the air w l be fresher and pur er when the mine is ventilated by a split system than when a 3 the ir traverses each working face and entry . ( ) Some mines vary s r l greatly a rega ds the generation of methane .