In brief
Chemical protective coveralls are classified from Type 1 to Type 6 according to the form of exposure they protect against; Type 3 is tested against liquid jets, Type 4 against spray, Type 5 against dry dust and Type 6 against limited splashes. The type number does not tell you how long the coverall will resist which chemical; for that, the manufacturer's permeation data must be checked. If a contaminated coverall is not removed in a set order with its outer surface turned inwards, contamination is carried onto the skin and into the clean area.
What does a chemical protective coverall protect against, and what not?
When cleaning a reactor, in a paint booth or when removing asbestos-containing material, workers may appear to be wearing the same white coverall. Yet the classes of these coveralls, the forms of exposure they are tested against and their resistance times differ greatly. Choosing a chemical protective coverall does not start with the sentence "we've given them coveralls" but with the question of which chemical reaches the worker in which form (dust, splash, spray, jet).
Under Art. 5 of the Regulation on the Use of PPE, personal protective equipment is used when the risk cannot be prevented by collective protection measures or work methods; in other words, a coverall does not replace a closed system, local exhaust ventilation or automation. Article 6 of the same Regulation requires PPE not to create additional risks itself, to fit the wearer properly, to carry a CE mark and a Turkish-language user manual, and for PPE used together not to impair each other's protection. Coveralls, gloves, boots and respiratory protection should therefore be chosen as a single set. For the general selection steps, see our article on how to choose PPE.
From Type 1 to Type 6: classes and standards
Chemical protective clothing receives a "type" number according to which test the coverall passes as a whole. The lower the number, the greater the tightness:
| Type | Exposure protected against | Relevant standard | Typical example of use |
|---|---|---|---|
| Type 1 | Gas and vapour (gas-tight) | TS EN 943-1 | Emergency response, highly toxic gas |
| Type 3 | Pressurised liquid jet | TS EN 14605 | Tank and line cleaning, acid-base transfer |
| Type 4 | Saturating liquid spray | TS EN 14605 | Pressure washing, pesticide application |
| Type 5 | Airborne dry particles | TS EN ISO 13982-1 | Dust, fibres, asbestos removal work |
| Type 6 | Limited liquid splash and light spray | TS EN 13034 | Low-risk splashes, paint preparation |
In addition, other markings may appear on the coverall's label. TS EN 1149-5 indicates antistatic properties; this only works when the worker is earthed through conductive footwear. TS EN 14126 indicates protection against infective agents, and TS EN 1073-2 against radioactive particles. Products marked "PB [3]", "PB [4]" or "PB [6]" are items such as aprons and sleeves that protect only part of the body.
Because chemical protective clothing protects against substances harmful to health, it is in the highest risk category in PPE legislation, Category III. The CE mark must therefore be accompanied by the four-digit number of the notified body. For the general framework of PPE use in the workplace, see our article on the Regulation on the Use of PPE.
Type 5 and 6 coveralls: the limits of disposable coveralls
The product most often seen on site is a disposable coverall marked both Type 5 and Type 6. These coveralls provide good protection against dust and light splashes; however, they have three limits:
- They do not resist jets and spray. During pressure washing or when working with chemicals flowing from a hose, a Type 5-6 coverall quickly gets wet and can let liquid through.
- The seam type matters. In coveralls with simple stitched seams, needle holes are paths through which fine dust can pass. For work with a high risk of dust and splashes, products with taped seams should be chosen.
- They are not reused. The coverall is thrown away when torn, when wet or at the end of the shift. Putting a contaminated coverall back on the next day means carrying the chemical directly onto the skin.
The openings that Type 5 and 6 coveralls leave at the wrists, ankles and face edge are taped at the junctions with gloves, boots and mask. For how to prepare the coverall and these junctions in asbestos removal work, see our article on asbestos removal work.
Painting coveralls and selection by chemical
Two questions decide the choice of a painting coverall: is the paint sprayed or applied by brush and roller, and is it solvent-based? With spray painting, mist particles and solvent vapour reach every part of the coverall. With solvent-based paints, the coverall must withstand not only splashes but also the permeation of the solvent. In paint booths with an explosive atmosphere, an antistatic coverall and conductive footwear should be considered together. For booth risks, see our article on paint booth and painter risks.
When selecting by chemical, distinguish between three concepts:
- Penetration: Liquid physically passing through seams, zips or pores. Type tests measure this.
- Permeation: The chemical passing through the material at molecular level. It is invisible; the manufacturer gives the breakthrough time in minutes for each chemical.
- Degradation: The material hardening, swelling or cracking as a result of contact with the chemical.
Look for the substance you use, or its closest component, in the coverall manufacturer's chemical permeation table. If there is no table, or the substance is not on the list, the product has not been validated for that job. You can read which PPE the chemical you use requires in Section 8 of its safety data sheet. The same logic applies to gloves; details are in our article on choosing work gloves.
You can make an initial selection by job as follows; the final decision is made according to the risk assessment and the manufacturer's data:
| Job | Form of exposure | Starting choice |
|---|---|---|
| Bagging powder products, dusty maintenance | Dry particles | Type 5, taped seams |
| Water-based paint by brush and roller | Limited splashes | Type 6 |
| Solvent-based spray painting | Mist, vapour | Type 4, or the Type 5-6 the manufacturer recommends for spray painting; antistatic |
| Tank and line cleaning, chemical transfer | Jets, heavy liquid | Type 3, material chosen for the chemical |
A closed coverall prevents heat loss. In a person working in a hot environment in a Type 3-4 coverall, heat stress develops rapidly; work and rest periods must be planned. For the measurement approach, see our article on industrial heat stress and WBGT.
Coverall removal sequence: without spreading contamination
When a contaminated coverall is removed incorrectly, chemicals or dust on the outer surface pass to the hands, neck and clean clothing. The coverall removal sequence should be a written instruction and demonstrated in practice:
- Stop at the boundary of the contaminated area. Removal takes place at a designated point between the contaminated and clean zones.
- Clean the outer surface. A Type 3-4 coverall contaminated with liquid chemicals is washed down according to the procedure. The surface of a dusty Type 5 coverall is cleaned with a HEPA-filtered vacuum or a damp cloth.
- Remove the outer gloves. If double gloves are used, the outer gloves come off first; the inner gloves stay on until the very end.
- Pull the hood back. The hood is folded back so that its outer surface faces inwards.
- Open the zip and peel it off the shoulders. The coverall is rolled down with its inner surface facing out. Where possible, a helper assists by holding the outside of the coverall.
- Remove the arms and legs. The coverall is removed together with the boots or peeled off over them and placed directly into a sealable waste bag.
- Respiratory protection comes off last. The mask is removed after the coverall has been taken off and the person has moved away from the contaminated area; then the inner gloves are removed and the hands washed.
Trials, training and records
A coverall should be chosen by trying it on the worker, not from a size chart. It should be checked that the seams are not strained and the sleeves and legs do not ride up when squatting, reaching and climbing ladders. Art. 6 of the Regulation on the Use of PPE also requires workers to be informed about the risks the PPE is to be used against and to receive practical training. With tight-fitting masks worn together with coveralls, the mask fit test should not be forgotten.
The type, size and replacement frequency of the coveralls issued should be recorded; for this, you can use the table structure in our article on PPE issue and replacement tracking. The administrative fine for not providing suitable PPE is applied per worker; you can calculate the current amount in the OHS administrative fines tool.
In Bursa Sistemer's OHS specialist service, we select PPE together with the chemical inventory and risk assessment at businesses in Bursa and the surrounding provinces, and demonstrate the coverall removal sequence through practical training. For risks specific to chemical and plastics businesses, see our chemicals and plastics sector page.
Frequently Asked Questions
What does a Type 5 6 coverall mean?
It shows that the coverall has passed both the Type 5 test (against airborne dry particles) and the Type 6 test (against limited liquid splashes). It is suitable for dust and light splashes; if there is a liquid jet or heavy spray, a Type 3 or Type 4 coverall is needed.
How many times can a disposable coverall be worn?
As the name says, once. A torn, wet or contaminated coverall is replaced immediately, and even if it remains intact, at the end of the shift. If the manufacturer's user manual gives a different period, follow that.
How do I know whether a coverall resists a chemical?
The type number does not answer this question. Check the breakthrough time of the chemical you use in the manufacturer's chemical permeation table and compare it with the duration of the task.
Does the coverall or the mask come off first?
The coverall first, then the mask. The mask is removed after the contaminated coverall has been taken off and the person has moved away from the contaminated area; this way, dust raised while removing the coverall is not inhaled.
A certified specialist matched to your hazard class: site inspections, approved logbook, training plan, annual plan and report follow-up.
Bursa SİSTEMER OSGB Technical Team — written from the field experience of our OHS specialists and workplace physicians. Legal information is valid as of the publication/update date; contact us for an assessment specific to your business.