RN53 Radon Detector. RN53-STK Starter Kit

Transcription

1 The RN53-STK Starter Kit has everything yu need t kick-start yur prject and is a great tl fr develpers: Prf f cncept prttypes as well as final cmmercial slutins. fr educatinal use: Natural science curses and practical lab experiments. The RN53-STK Starter Kit includes ne RN53 Radn Detectr (preinstalled in the measuring chamber) ne RN53 cnnecting cable ne 165cm 3 measuring chamber ne RN53 Tester RN53 Radn Detectr At the heart f the RN53-STK Starter Kit is the RN53 Radn Detectr. Fr a detailed verview f the features and characteristics f the RN53 Radn Detectr, please refer t the RN53 Datasheet The RN53 Radn Detectr generates apprx. 90 pulse cunts per hur ±10% at 1000Bq/m 3 (installed in the 165cm 3 measuring chamber with +400V vltage applied). Rev Cpyright Tevis Sensr Technlgies Ltd

2 RN53 Tester With the RN53 Tester a radn envirnment can be established fr testing the functinality f the RN53 Radn Detectr. The RN53 Tester cnsists f a sealed aluminum capsule which cntains small amunts f radium paint. Radium paint was widely used fr 40 years n the faces f luminus watches, cmpasses, and aircraft instruments. The main radiactive decay prduct f luminus paint is radn, a clrless, drless, radiactive gas. The RN53 Tester will establish in a clsed 7 liter cntainer a radn cncentratin between 700 and 1000 Bq/m³, after reaching its equilibrium in three days. The cncentratin and the quantity f radn are at such a lw level, that it des nt have an adverse effect n human health r the envirnment. When radn is released in free air, it will vlatilize and decay in a shrt perid f time. The RN53 Tester prvides the ideal envirnment t perfrm functinal tests n prttypes f radn measuring instruments built arund the RN53 detectr. The RN53 Tester hwever, is nt suitable fr calibratin f radn mnitrs. Technical Details n the RN53 Tester Outer dimensins: 40mm diameter, 15mm high Radn surce: Radium paint in a sealed capsule Internal shielding: 1mm f lead Activity: < 0.05µCi Half-life: 1500 years A radn cncentratin f 700 t 1000 Bq/m³ will establish In a clsed 7 liter cntainer Quick Functinal Test 1. Perfrm the test in a shady, glmy envirnment withut excessive lighting 2. Remve the sticker n the bttm f the measuring chamber 3. Cnnect VCC f the RN53 Radn Detectr t 4.5V 4. Cnnect OUT f the RN53 t a pulse cunter r t an scillscpe 5. Take an LED flashlight and swivel the light beam thrugh the hle n the bttm f the measuring chamber 6. Yu shuld detect nw a number f pulses n the cunter r n the scillscpe 7. In case n pulses are detected, check fr prper wiring and the adapter cnnectins t the sensr 8. Put the sticker back t the bttm f the measuring chamber when the test is finished Rev Cpyright Tevis Sensr Technlgies Ltd

3 Applicatin Ntes General Infrmatin The efficiency f cllecting the 222 Rn prgeny 218 P and 214 P depends n the cnstructin f the measuring chamber and n the electrstatic field applied t the measuring chamber. Bias vltages between +200V and +500V are recmmended. Experimental Radn Test Cntainer Experimental Radn Test Cntainer Nte: This experimental set-up is nt suited fr the calibratin f radn mnitrs The equilibrium f the radn gas in the cntainer is reached after three days. Keep in mind that measuring radn cncentratin is nt a matter f secnds r minutes. Sampling perids shuld be at least ne hur. Suggested Cnstructin fr a Cmmercial Radn Mnitr Rev Cpyright Tevis Sensr Technlgies Ltd

4 Example fr a Battery perated Experimental Radn Mnitr Technical Details Measuring chamber: 165cm 3 Radn sensr: RN53 (TEVISO); V in : 4.5V/20µA Pwer supply: 3x 1.5V Type AA battery Chamber bias supply: IMEX geiger tube HV supply (Ebay); V in : 4.5V/10µA, V ut : 400V Pulse cunter: MDMU0000 ( / V in : 4.5V/50µA Measurement sensitivity: 95 cunts per hur ±10% at 1000Bq/m 3 Battery duratin: 3 years f uninterrupted peratin Rev Cpyright Tevis Sensr Technlgies Ltd

5 Abut Radn Radn ( 222 Rn) is a clrless, drless and tasteless gas that is radiactive. 222 Rn is prduced by the radiactive decay f radium ( 226 Ra), which is fund wrldwide in uranium res, phsphate rck, shale, metamrphic rcks such as granite. The density f 222 Rn is ten times higher than air. 222 Rn belngs t the radium ( 226 Ra) and uranium ( 238 U) decay chain, and has a half-life f 3.82 days. Its fur first decay prducts (excluding marginal decay schemes) are very shrt-lived, meaning that the crrespnding disintegratins are indicative f the initial radn distributin. Its decay ges thrugh the fllwing sequence: 222 Rn, 3.82 days, alpha decaying t P, 3.10 minutes, alpha decaying t Pb, 26.8 minutes, beta decaying t Bi, 19.9 minutes, beta decaying t P, ms, alpha decaying t Pb, 22.3 years, beta decaying t Bi, days, beta decaying t P, days, alpha decaying t Pb, stable. Radn in Daily Life Radn is a majr cntributr t the natural radiactivity f the atmsphere near the earth s surface. With its half-life f 3.82 days it has plenty f time t diffuse thrugh small cracks in rcks and thrugh the sil and t enter the atmsphere. Sme level f radn will be fund in all hmes. Radn expsure in hmes and ffices may arise frm certain subsurface rck frmatins, and als frm certain building materials (e.g. granite). The greatest risk f radn expsure arises in buildings that are airtight, insufficiently ventilated, and having leaks, penings r cracks, that allw radn-cntaining air frm the grund int basements and dwelling rms. Radn cncentratin varies greatly with seasn and atmspheric cnditins. In the same lcatin it may differ by a factr f tw ver a perid f 1 hur. Als, the cncentratin in ne rm f a building may be significantly different frm the cncentratin in anther. Radn has been cnsidered the secnd leading cause f lung cancer and the leading envirnmental cause f cancer mrtality. Accrding t WHO recmmendatins [1] the average annual radn cncentratin shuld nt exceed 300 Bq/m³ in the nrmal ccupancy area in rder t avid adverse health effects. Rev Cpyright Tevis Sensr Technlgies Ltd

6 Reference [1] Measuring Radn Because radn cncentratins can vary seasnally, it is best practice t mnitr radn levels ver a lng perid f time. Ideally, this wuld be ne full year because this allws yu t determine the annual average radn cncentratin in a particular dwelling rm. Sampling times f at lest ne hur are recmmended. Radn cncentratin mnitred ver a perid f 48 hurs in a rm in the basement f the building Rev Cpyright Tevis Sensr Technlgies Ltd

7 Disclaimer Neither the whle nr any part f the infrmatin cntained in, r the prduct described in this datasheet, may be adapted r reprduced in any material r electrnic frm withut the prir written cnsent f the cpyright hlder. This prduct and its dcumentatin are supplied n an as is basis and n warranty as t their suitability fr any particular purpse is either made r implied. Tevis Sensr Technlgies will nt accept any claim fr damages hwsever arising as a result f use r failure f this prduct. Yur statutry rights are nt affected. This prduct r any variant f it is nt intended fr use in any medical appliance, device r system in which the failure f the prduct might reasnably be expected t result in persnal injury. This dcument prvides preliminary infrmatin that may be subject t change withut ntice. Rev Cpyright Tevis Sensr Technlgies Ltd