NIST SRM 1828
Definition
A series of NIST-certified reference material aqueous ethanol standards (0.02 to 0.40 per cent w/v) used to calibrate forensic blood ethanol analytical methods in the United States, providing a traceable anchor to the national metrology system.
- Material
- Certified aqueous ethanol reference solutions
- Concentration range
- 0.02 to 0.40 per cent w/v
- Issued by
- NIST
- Use
- Calibrating forensic blood ethanol methods in the US
Common questions
Why is a certified standard needed instead of a lab-prepared ethanol solution?+
A lab-prepared solution has no documented chain of traceability to a national metrology institute, so its accuracy cannot be independently verified. SRM 1828 carries a certificate of analysis that lets a lab defend its calibration under cross-examination.
Does SRM 1828 calibrate breath alcohol instruments too?+
It is formulated for aqueous solutions used with headspace GC and similar wet-chemistry blood alcohol methods. Breath alcohol simulators typically use separate certified solutions designed for vapor equilibrium, not this SRM directly.
Related terms
- 2100:1 Partition Ratio
- The conventional blood/breath partition assumption used by breath alcohol analysers worldwide: 2100 mL of venous blood contains the same mass of ethanol...
- Beta Elimination Rate (Beta)
- The rate at which BAC falls during the post-absorptive phase of alcohol metabolism, expressed as mg/100 mL/hour. Population mean approximately 15 mg/100...
- Blood Alcohol Concentration (BAC)
- Mass of ethanol per unit volume of whole blood, expressed as mg per 100 mL (equivalent to mg/dL or mg%), or as...
- DB-ALC1 / DB-ALC2
- A matched pair of Agilent fused-silica GC columns used for dual-column orthogonal confirmation of blood ethanol. DB-ALC1 uses a polyethylene glycol stationary...
- Internal Standard (IS)
- A compound chemically near-identical to the analyte, often a deuterated isotopologue (d3-morphine, d5-EDDP, d5-alprazolam, pyrene-d10), spiked into every sample at a known...
- Partition Coefficient (K)
- The ratio of analyte concentration in the liquid phase to concentration in the gas phase at equilibrium. For ethanol in blood at...
- Sodium Fluoride / Potassium Oxalate (Grey-Top Tube)
- The standard blood collection tube for forensic ethanol analysis. Sodium fluoride inhibits microbial fermentation (which would produce artefactual ethanol post-collection); potassium oxalate...
- Static Headspace
- A sample preparation technique in which a sealed vial is heated until volatile analytes reach thermodynamic equilibrium between the liquid matrix and...
- Widmark Factor (Rho / R)
- A dimensionless pharmacokinetic constant that represents the distribution of ethanol across body water. Averages approximately 0.68 for adult males and 0.55 for...