Document yqQ2ppk07Zmjvkwb4rvEGBbV

JV !< AKH/CXH/3II 75 Dr. 3. Holmes 24th March, 1967. AUttpm..BMtV Ifflll.r. 8prBY fibre Dlvl.lon In reply to your got*, datsd 22nd March, I have listed the Man fibre count* for the relevant location, in the Spray Fibre Division, lhere follow* abort dlacuealon of the results. Stacking or UnatackIn* cf bass of asbestos Allte Platform Spray Fibre Drue Mixer Platforna Spray Fibre Muchanlcal Bagging Osneral Ataosphere 46 fibres per c. 19 12 - " - 11 " W * if 1) Stacking and Pnatacklns p>* sampling at points In the fibre warehouse, where bags of crude asbestos are handled, did not eonaence until May of last year, and since then the following counts have been obtained i- 13, 156, 34, 40, 20, 28, 62 and 17 fibres per *,*. These relatively high results are for all three nn--nn types of asbestos used (see not* 5). Only on* saaple has been taken whilst Croddollte was being handled (4o f/e.o.) and on that occasion It was noted that respirators were worn by the operatives concerned. Jh` 2) Alltc/Snray .Fibre Platforms and Mechanical h,d. For detailed lnforaatlon of the dust levels at the** location* the dust survav repert graphs. ( which era attachsd) should be consulted. The trend lines indicate that thare has bean a ataady dsterloratlon In th* condition* ovar th# past 4 yaara, except at the bagging unite, where several duet control aeaeures have been Introduced recently.. It will be also noticed that th* results for th* Meatran# Filter sonpis* (taken alnca January 196;) fluctuate acre than those for the 'Ottway' L.R.T.P. This la du* to th* shorter sampling period necessary to collect a countable' sample cn the membranes. 3) Osneral Atmosphere Stapling the general envlccnasnt In th# Spray Fibre plant cowesnctu In January 1966. Th* result* are Indicative of th* dust hatard that 'unprotected' personnel! are expoaad to and therefore they are rather disturbing, especially as counts a* high as 9.3 and 11.4 have been obtained. contd / \ contd. - 2- 4) PtlMlttl Thar* are no flguroa for this stage of manufacture where the bagged Spray Fibre materials are handled. Ms will investigate the possibility of a dust hasard, but It Is considered that th* levels bare are low as th* paperlined bag* appear Impsrvlcua to dust. 5) Ccnnarlarn ef Dluo and -<hlto Asbestos dust count* As you are aware, the dust lavala In cur factorlaa depend upon aany variables and, from the results of past T.B.A. routine surveys, thor* Is s good Indication that Crocldollt* la dustier than fhryaotils whan processed on textile machinery. However, In the Spray Fibre Dlvlalcn th* level doss not appear to depend upon th* fibre to th* same extant, but depends much more cn the saapllrvi position, the opening of the lerry doors (hence cl lastic ccndltlcns). and ssvcral other factors, therefor* the email number of results obtained to date on the platforms, and at th* begging units, where 1.6.3 (Spray material containing Crocldollt*) is being manufactured, are not appreciably different. Aa at tho T.B.A. factory locations at Hindiey Oreon, it la Intended to Increase th* sampling rata on aachines processing Crocldcllte. \r JV* IH/H3 I. Harness Physics Research Department.