Overview
ISO 4874:2020 - Tobacco: Sampling of batches of raw material - General principles sets out the general principles and procedures for sampling batches of raw tobacco to assess either the mean values of one or more characteristics or the heterogeneity of those characteristics. The standard applies to raw leaf and pretreated tobaccos (flue-cured, air-cured, sun-cured, fire-cured and several pretreated forms). Manufactured tobacco products (ready-for-sale items) are explicitly excluded.
Key topics and technical requirements
- Scope and purpose: Sampling aimed at estimating mean values or assessing heterogeneity of physical, chemical, botanical or organoleptic characteristics.
- Contractual arrangements: Contracts should specify sampling stages, responsible parties, characteristics to be measured, designated laboratories, and maximum time between sampling and analysis.
- Sampling units and definitions: A sampling unit is a separately packaged part of a consignment (bale, sack, case). For bulk tobacco, a consignment mass m kg can be notionally divided into m/100 sampling units.
- Selection methods:
- Random sampling - each unit has equal selection probability.
- Periodic systematic sampling - select units h, h+k, h+2k, … where nk ≤ N < n(k+1) (N = total units, n = units to sample).
- Increments and samples:
- Minimum increment: three packets tied together (hands), or 50 leaves (if untied), or 500 g for certain forms (stems, reconstituted, threshed).
- At least three increments per sampling unit, taken from upper, middle and lower thirds (or evenly distributed if more).
- Definitions: increment → single sample (all increments from one unit) → gross sample → reduced sample → laboratory/test sample.
- Equipment and containers: Use clean, dry, non-reactive sampling tools. Containers must be chemically inert, airtight, preferably opaque; samples stored cool, dry, protected from light and odour.
- Treatment of damaged units: Sample separately or exclude depending on whether damage affects the characteristic being measured.
- Reporting: Sampling report must record origin, consignment/batch numbers, masses, packing, number/position of increments, composition of single/gross/reduced/laboratory samples, signatures and date.
Applications and who uses it
- Quality control and acceptance testing for raw tobacco suppliers, processors and buyers.
- Laboratories conducting compositional, physical or organoleptic testing.
- Regulatory or contractual inspections where standardized sampling is needed to support claims about batch mean values or heterogeneity.
- Useful in procurement, inventory verification, dispute resolution and batch certification.
Related standards
- ISO 8243:2013 - sampling cigarette material (referenced for cigarettes-derived tobacco).
- ISO 3534-2 - terminology related to sampling definitions (referenced for sampling unit definition).
Keywords: ISO 4874:2020, tobacco sampling, raw tobacco sampling, sampling protocol, sampling units, sampling report, laboratory sample, heterogeneity, mean value, quality control.