Dear Ricardo

your question is to "high level". Therefore I try we other way:

Any REAL_SUB you need. you must maintain by your own !

Any LIST_SUB, PURE_SUB etc. you will need you need to maintain by your own. The data providing is "only" related (in most cases) to LIST_SUB/PURE_SUB; therefore the number of objects are the "driver" to decide if a data provide can help. On the top: it depends on the need how many languages you need to support in the phrases part. You must prepare at least something like 5000 phrases to get a MSDS prepared. On the top you need identifiers for the specificaiotns (e.g. NUM CAS etc. etc.)

With out rule sets the user need to do the work manually; therefore once again: based on the amount of REAL_SUBs rulests can dramatically simplify the amount of work for maintaining the data. Keep in mind. you need on top experts for Dangerous goods management; is is normally the most important stuff in parallel to MSDS generation.

Let us now assume you would really start form scratch and you would need 5000 phrases in at least 20 languages. First step is: you need the texts ...some are regulatory driven and you must use the text in "legal" documents; so you need to insert them as phrase textes. Per phrase therefore the colleciotn of the translations et.c can take time (outside of SAP) 4 weeks or more. If you have the texts and you have an experienced person who is able to use the transaction: per phrase you can imgaine something like at max 30 min; as well you could use a "phrase" import (if you have the phrase texts and codes in a "flat file". Then the maintenance can be done as well in one run in not more than 1 hour. So the timeintensive step is: collecting the data and getting the translations

Maintaining the data on REAL_SUB, LIST_SUB, PURE_SUB level can take up to 4 weeks (basaed on complexity of composition etc.). Therefore: in contrast to modules like SAP SD, SAP MM and others the customizing etc. steps required to prepare EHS "ready" is on same level, but the amount of time to collect the data etc. is at least 10 times higher; keep in mind: once a year a lot of regulations are changing and new regulations are coming up and to a certain extent you are "restarting" the story (maintain data, add need data, add new phrases etc.) Discussion in this FORUM has shown taht on the top the WWI layout for can be a challenge if you do it by your own.

So depending on the size of the company, the people who could act in the system, a data provider can cleary help. Keep in mind: SAP is providing a lot on top services (and they enlarge their service); may be ask SAP to get an idea of what money would be involved if you would like to use their services. Currently I would imagine that not more than 5 data providers are acting on the market on the same level as SAP is doing it.

Conclusion: for preparing the data in the system you should assume at least a period of 6 months and lots of persons (mandays). The story as such depends on your history. E.g. do you have a current legacy system in which EHS data is stored? If answer is yes you could have the need to migrate data etc.

May be check:

SAP EHS Management for Beginners

Your topic does have some references therein