40 C.F.R. § 1065.644

Current through May 31, 2024

Section 1065.644 - Vacuum-decay leak rate

This section describes how to calculate the leak rate of a vacuum-decay leak verification, which is described in § 1065.345(e) . Use the following equation to calculate the leak rate n_leak, and compare it to the criterion specified in § 1065.345(e) :

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Where:

V_vac = geometric volume of the vacuum-side of the sampling system.

R = molar gas constant.

p₂ = vacuum-side absolute pressure at time t₂.

T₂ = vacuum-side absolute temperature at time t₂.

p₁ = vacuum-side absolute pressure at time t₁.

T₁ = vacuum-side absolute temperature at time t₁.

t₂ = time at completion of vacuum-decay leak verification test.

t₁ = time at start of vacuum-decay leak verification test.

Example:

V_vac = 2.0000 L = 0.00200 m³

R = 8.314472 J/(mol · K) = 8.314472 (m²· kg)/(s²· mol · K)

p₂ = 50.600 kPa = 50600 Pa = 50600 kg/(m · s²)

T₂ = 293.15 K

p₁ = 25.300 kPa = 25300 Pa = 25300 kg/(m · s²)

T₁ = 293.15 K

t₂ = 10:57:35 a.m.

t₁ = 10:56:25 a.m.

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40 C.F.R. §1065.644

79 FR 23795, Apr. 28, 2014