Gas or Vapour to be Measured Chemical Formula	Réf tube	Gastec Tube No. & Name	Measuring Range (ppm)	No.of Pump Strokes	Shelf Life (year)	Note		TLV- TWA,C (ACGIH) (ppm)
Heptane CH3(CH2)5CH3	101	Gasoline(Petrol)	0.6-1.2%	1/2	3	-		-
			0.03-0.6%	1
			0.015-0.03%	2
	101L	Gasoline(Petrol)	1000-2000	1	3	-
			30-1000	2
	103	Hydrocarbons (LowerClass)	0.84-1.68%	1/2	2	++
			0.07-0.84%	1
			0.035-0.07%	2
	105	Hydrocarbons (HigherClass)	180-2700	1	3	-
			90-180	2
Hexamethylenediamine H2N(CH2)6NH2	180L	Amines	1.55-31	1	2	T		-
n-Hexane CH3(CH2)4CH3	102H	n-Hexane	0.6-1.2%	1/2	3	-		50
			0.03-0.6%	1
			0.015-0.03%	2
	102L	n-Hexane	50-1200	1	3	-
			10-50	5
	103	Hydrocarbons (LowerClass)	0.6-1.2%	1/2	2	++
			0.05-0.6%	1
			0.025-0.05%	2
	105	Hydrocarbons (HigherClass)	160-2400	1	3	-
			80-160	2
Hexone	See Methyl isobutyl ketone
2-Hexyl alcohol CH3(CH2)3CH(OH)CH3	141L	Ethyl acetate	75-2400	3	2	T		-
Hexylamine CH3(CH2)5NH2	180	Amines	9-180	1	3	T		-
	180L	Amines	0.65-13	1	2	T
Hydrazine N2H4	185	Hydrazine	0.1-2	5	3	H		0.01
			0.05-0.1	10
Hydrocarbons (HigherClass)	105	Hydrocarbons (HigherClass)	200-3000	1	3	-		-
			100-200	2
Hydrocarbons (LowerClass)	103	Hydrocarbons (LowerClass)	1.2-2.4%	1/2	2	++		-
			0.1-1.2%	1
			0.05-0.1%	2
Hydrogen H2	30	Hydrogen	0.5-2%	1	3	-		-
Hydrogen bromide HBr	15L	Nitricacid	0.8-16	1	3	H		C 3
Hydrogen chloride HCl	14M	Hydrogen chloride	500-1000	1/2	3	-		C 5
			20-500	1
			10-20	2
	14L	Hydrogen chloride	20-76	1/2	3	-
			1-20	1
			0.2-1	2-5
	80	Acid gases	8-160	2	2	-
	8HH	Chlorine	1.5-30%	1/2	3	-
Hydrogen cyanide HCN	12H	Hydrogen cyanide	0.05-1.6%	1	3	T		C 4.7
	12M	Hydrogen cyanide	800-2400	1/2	3	-
			50-800	1
			17-50	2
	12L	Hydrogen cyanide	60-120	1/2	2	H
			2.5-60	1
			1.25-2.5	2
			0.36-1.25	5
	12LL		0.2-7	2	2	H
Hydrogen fluoride HF	17	Hydrogen fluoride	20-100	1	3	H		C 3
			0.5-20	4
			0.25-0.5	7
Hydrogen peroxide H2O2	32	Hydrogen peroxide	0.5-10	5	3	T		1
Hydrogen sulphide H2S	4HT	Hydrogen sulphide	20-40%	1/2	3	-		10
			2-20%	1
			1-2%	2
	4HP	Hydrogen sulphide	10-20%	1/2	3	-
			0.5-10%	1
			0.25-0.5%	2
	4HH	Hydrogen sulphide	2-4%	1/2	3	-
			0.1-2%	1
	4H	Hydrogen sulphide	2000-4000	1/2	3	-
			100-2000	1
			10-100	2-10
	4HM	Hydrogen sulphide	800-1600	1/2	3	-
			50-800	1
			25-50	2
	4M	Hydrogen sulphide	250-500	1/2	3	-
			25-250	1
			12.5-25	2
	4L	Hydrogen sulphide	120-240	1/2	3	-
			10-120	1
			1-10	2-10
	4LL	Hydrogen sulphide	60-120	1/2	3	-
			2.5-60	1
			0.25-2.5	2-10
	4LT	Hydrogen sulphide	2-4	1/2	2*	T
			0.2-2	1
			0.1-0.2	2
	4LK	Hydrogen sulphie	20-40	1/2	3	-
			2-20	1
			1-2	2
	45S	Hydrogen sulphide, sulphur dioxide	60-120	1/2	3	+
			2.5-60	1
			1.25-2.5	2
Hydrogen sulphide +Sulphur dioxide (Total Quantification) H2S+SO2	45H	Hydrogen sulphide +Sulphur dioxide	4-8%	1/2	3	-		2
			0.2-4%	1
			0.02-0.2%	2-10
4-Hydroxy-4-methyl @-2-pentanone	See Diacetone alcohol

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