Metal and Nonmetal National Mine Rescue Contest Rules

3. Con tes tants may re turn to cor rect any un cor rected de fi -cien cies at any time within the time limit.4. Five (5) dis count points per alarm point will be as sessedfor any in cor rectly set alarms.5. Five (5) dis count points will be as sessed for each in -stance of in cor rect pro ce dure or equip ment use dur ingcalibration.6. Fif teen (15) dis count points will be as sessed for each in -cor rect gas read ing.7. No dis counts will be as sessed for re plac ing nondefi cient sen sors, as long as the re sult ing gas read ingsand alarm points are cor rect.8. Each con tes tant shall have a max i mum of thirty (30) min -utes to com plete the bench por tion and gas-test ing por tionof the con test. There will be a five (5) min ute warn inggiven by the judge when time is about to ex pire.9. For com ple tion, the con tes tant must have the in stru mentfully as sem bled and op er at ing and have com pleted allfour gas read ings within the al lowed time.GAS BOX TESTING1. The gas test ing will con sist of sub ject ing the in stru ment to anun known mix ture of O 2 , CH 4 , CO and NO 2 . The con tes tantwill be ex pected to re port all 4-gas con cen tra tions within ac -cept able lim its in the fol low ing or der: O 2 , CH 4 , CO, NO 2 .2. Fif teen (15) dis count points per gas will be de ducted if acon tes tant does not re port gas con cen tra tions within ac -ceptable limits:a. Oxygen readings are considered to be correct ifwithin plus or minus 0.5% by volume;b. Methane readings are considered to be correct ifwithin plus or minus 0.2% by volume;c. Carbon Monoxide readings are considered to becorrect if within plus or minus 20% of the actualvalue present; andd. Nitrogen Dioxide readings are considered to be correctif within plus or minus 2 ppm of the actual value present.46