Recognise the agent
The INSST INFOCARQUIM entry identifies benzene by CAS 71-43-2 and records its classification as a category 1A carcinogen and 1B mutagen. It must not be confused with other compounds whose names contain “benzene”: precise identification matters.
It may occur in petrochemical activities and mixtures such as petrol. The safety data sheet and process information help locate it, but emissions and waste that do not arrive labelled as a new product must also be considered.
Examine intermittent operations
The inventory must describe where the substance is stored, circulates or may be released. A facility closed during production may present different exposures during sampling, opening, cleaning, repair or material removal.
Identify who performs each task, its duration, frequency and proximity to the source. External personnel need information about the hazard and intervention conditions; generic access authorisation does not resolve that coordination.
Substitute and contain
In Spain, Royal Decree 665/1997 requires substitution of the carcinogenic agent where technically possible. If substitution is not possible, closed systems are required and, where these are not technically possible, exposure must be reduced to the lowest technically possible level.
Alternative selection must check composition and hazards. Changing the trade name without reviewing the formulation does not demonstrate preventive improvement.
Measure what is actually inhaled
The INSST FTA-05/A24 method sheet describes a specific benzene sampling and analysis method. The strategy must represent tasks and exposure groups, rather than rely on an ambient measurement away from the worker.
Results are compared with current limits and reference periods. Older technical sheets may retain useful methods, but historical figures must not be used without checking current legislation.
Consider every route of entry
Alongside inhalation, assessment must address contact with contaminated liquids. Hand and body protection is selected according to permeation, task and actual conditions; a general-purpose glove provides no universal guarantee.
Hygiene and clothing and waste management must prevent contamination from spreading. Biological monitoring, where appropriate and determined by health professionals, provides supplementary information: it does not replace technical measures or environmental assessment.
Retain useful information
Records should connect the substance, tasks, exposed people, controls and checks. When a process changes or an incident occurs, this traceability helps review which conditions changed and which measures need adjustment.
Health surveillance must be specific and confidential. Absence of symptoms does not demonstrate absence of exposure or justify delaying technical improvements.
Hypothetical example: sampling
A facility identifies benzene in a process stream. Routine operation is enclosed, but sampling uses a manual opening. The preventive team analyses that task and considers closed sampling compatible with the process.
After the change, it checks exposure and updates instructions. Improvement is verified in the specific operation that created contact, not just in the plant’s general documentation.
