Work with biocides

1 General

1.1 Purpose

The procedure is meant to ensure that personnel working with biocides have sufficient information about biocides to handle these in a prudent manner, including the necessary use of protective gear.

1.2 Scope

The procedure covers all use of Chemical biocides in the company.

1.3 Target group and responsibility

1.3.1 Target group

The target group for this procedure is instrument technicians/automation technicians, drilling and well service personnel, inspectors, crane drivers, mechanics, process technicians, nurse and store keeper.

1.3.2 Responsibility

The owner of this document is responsible for the updating and revoking of this document when organisational or operational conditions so indicate.

1.4 Deviation Management

Applications for deviating from this procedure must be handled in accordance with procedure for non-conformity handling, 4920E.

1.5 Definitions

Biocides are chemicals used to kill micro-organisms through injection into water or oil, many biocides are toxic.

1.6 References


Regulations relating to execution of work, the Directorate of Labour Inspection (Order No. 703)


Regulation regarding threshold and limit values for occupational exposure


Regulations relating to use of personal protective gear at the workplace, the Directorate of Labour Inspection (Order No. 524)

Leaflet 539

Respiratory protection (2006), the Directorate of Labour Inspection

2 Control of biocide exposure

2.1 General

Examples of Biocides are chlorine, glutaraldehyde, quaternary amines.

Many biocides may pose a major inherent health hazard. It is necessary to use personal protective equipment when handling the products to control exposure.

2.2 Health effects and exposure

Biocides may pose the following health hazards:


  1. irritating

  2. caustic


  1. desiccating

  2. irritating

  3. caustic

  4. allergenic

  5. carcinogenic


  1. irritating

  2. caustic

  3. increase sensitivity


  1. toxic

  2. damages health

Some biocides are classified as carcinogenic.

The most important health hazards posed by a product will be summed up in the product's safety data sheet and chemirisk evaluation.

2.3 Health examination

Only handling biocides classified as carcinogenic require health examinations of personnel handling biocides. The extent and contents of the health examination shall be decided based on an assessment. If workers have been exposed to biocides in a manner that causes risk of damage to their health (i.e. during an accident). As far as the biocide is handled in closed systems, the health examination is not required. Contact occupational hygienist if in doubt.

2.4 Medical surveilance

No requirements have been set for medical surveillance of personnel handling biocides.

2.5 Personal hygiene

Wash the skin immediately if it comes into contact with biocides. Also, change workwear immediately if there is a risk of skin exposure after spills.

When the work operation has been completed, all soiled clothing shall be sealed, marked and disposed. Wash protective goggles and respiratory equipment in mild detergent.

Ensure proper personal hygiene before taking a break. Proper hand washing routines prior to coffee/smoking/meal breaks must be established and followed. Washing hands will prevent any biocides on the skin from penetrating the skin or being ingested orally during meal breaks.

2.6 Exposure limits

Exposure limits have not been set for all biocides, but biocide exposure must be reduced to the lowest possible level. Exposure limits have been established for some biocides, see the bullets below. The following exposure limits have been established by the Directorate of Labour Inspection (corrected for 12-hour shifts):

  • glutaraldehyde: 0.12 ppm / 0.48 mg/m3

  • formaldehyde: 0.3 ppm / 0.36 mg/m3 (formaldehyde is prohibited for use offshore)

2.7 Possible exposure situations

Biocides are used in water injection, sea water treatment, production/export and utility systems.

Many of the biocide products are dispersed in a closed system. The use of closed systems reduces the risk of exposure compared with manual handling. A biocide is pumped from the biocide tank to the processing system where the biocide is needed. The risk of exposure is largest during filling the storage tank with biocides and when carrying out necessary maintenance on biocide tanks, pumps or distribution networks.

2.8 Personal protective equipment

When handling biocides and/or equipment containing biocides, the following protective equipment constitute the minimum requirement:

  • nitrile rubber gloves (other gloves may be recommended refer to the safety data sheet section 8 or chemirisk evaluation)

  • close fitting goggles or face shield

Chemical suite (mirochem 3000) and chemical boots are required when:

  • Handling biocides above 1 litre

  • When there is a risk of spills or leaks

  • Entering vessels that previously has contained biocides

In addition respiratory protective equipment (full face mask replacing shield or goggles) is required when

  • During opening of systems that contain large amounts of biocides or the work to be conducted has ha high risk of contact with biocides (full face mask with filter minimum AB/P3)

  • Handling biocides with high volatility (full face mask with filter AB/P3)

  • In areas with poor ventilation (fresh air, ref. document 5069)

  • Collecting spills (full face mask with filter AB/P3

  • Entering vessels (fresh air, ref. document 5069)

  • During work on systems that have not been flushed with water

I general it is not recommended to use contact lenses during handling of biocides.

If the personal protective equipment is un damaged and clean it can be stored in an appropriate manner (not together with biocides and chemicals) for later use

In general, using contact lenses when handling biocides is not recommended.

Contact the department manager or industrial hygienist if there is doubt regarding what protective equipment to wear.

3 Training

All involved parties must receive training in the health hazards posed by the properties of the chemicals and how to prevent injuries prior to work. The training can e.g. be given in HSE meetings as part of the review of the safety data sheet or chemirsik evaluation. Line management is responsible for ensuring that such training is provided.

Before putting a new biocide to use, information must be given regarding health hazards and how to prevent injuries.

All involved personnel shall review the chemirisk assessment if one is provided for the biocide planned used. All barriers in the chemirisk assessment must be followed.

If the chemirisk assessment deviate from the actual handling procedure, a new assessment must be conducted in collaboration with the occupational hygienist.

Training assistance can be given by an industrial hygienist, if needed.

4 Safe job analysis

A safe job analysis must be completed unless the work concerned is “routine work”, see Safe Job Analysis (SJA), dok. no. 3549.

5 Carrying out work

Work must be planned in a manner thet make the risk of biocide exposure as low as possible for all personnel are working in the area. Necessary personal protective equipment must be used during the entire work operation to avoid hazardous exposure.

Prior to commencing work with biocides, the personnel must ensure that they are familiar with the correct handling of the product. If it is assessed necessary barriers should be established to avoid exposure of third party personnel.

All containers must be labelled with the correctly and in compliance with the company and government requirements.

Leaks form containers and vessels must be corrected immediately. Drip trays should be established where there is a risk leakage.

5.1 Refilling station

Eye rinsing equipment, emergency shower and a sink for hand washing must in vicinity of biocide refilling stations.

The refilling connector stub must always be correctly labelled with the product name and warning pictograms. When changing biocides labelling must be updated the same day as new biocides are set in to use.

5.2 Equipment maintenance

Prior to opening pumps or other parts of the biocide system, the system section in question must be drained and flushed through with water. Pumps should also be rinsed with water if possible. This is done to reduce the biocide exposure risk when the system is opened.

Standard protective gear must be used in all maintenance operations where there is potential for biocide exposure, ref. Item 2.8 Personal protective equipment .

6 Calibration of injection pumps

Personal protective equipment must be used when calibrating biocide pumps, ref. Item 2.8 Personal protective equipment . Biocide pumps must be flushed through with water before commencing work. If calibration can be completed without opening the system (closed system) use of protective equipment beyond standard PPE is optional and the need for flushing with water can be evaluated.

7 Storage and waste removal

Spilled biocides must be contained immediately. Spills may be pumped or absorbed in dry inert material, as sand, soil or equivalent. Use of vacuum cleaner is not recommended. Smaller amounts may be flushed to drain (a closed drain is preferred) with large amounts of water.

Respiratory equipment as described in chapter 2.8 Personal protective equipment must be used.

Collected material shall be handled as hazardous waste. Refer to procedure 6354 “Transport, Storage and Handling of dangerous goods”.