Canada Adopts ISO 13857 — Safety Distances

This entry is part 4 of 7 in the series Guards and Guard­ing

Safety Distances

ISO 13857 2008, Figure 2 - Safety Distance for reaching over a protective structure
ISO 13857 2008, Fig­ure 2 — Reach­ing Over Pro­tec­tive Struc­ture

As part of the work on the 3rd Edi­tion of CSA Z432, Cana­da has decid­ed to adopt ISO 13857 as CAN/CSA-ISO 13857. The stan­dard was adopt­ed in 2015 with­out tech­ni­cal devi­a­tions.

Why ISO 13857?

CSA Z432 has long had por­tions of the infor­ma­tion in ISO 13857 in its annex­es — Annex C has tables for reach­ing through open­ings and reach­ing over struc­tures, much like the one above, that users have found use­ful over the years. Unfor­tu­nate­ly, these tables have also proved a bit con­fus­ing, as they are some­what dif­fer­ent than CSA Z432-04 Table 3. While nei­ther set of safe-dis­tance val­ues is less safe, the val­ues in Table 3 are very sim­i­lar to those used in the USA, which was the orig­i­nal source for that infor­ma­tion. The tables in CSA Z432-04 Annex C are infor­ma­tive, mean­ing they are pro­vid­ed as a help­ful guide to apply­ing the stan­dard, but they are NOT a manda­to­ry part of the stan­dard.

When Z432 was first being devel­oped in the late 1980’s, most machin­ery prod­ucts were com­ing to Cana­da from the US, so har­mon­i­sa­tion with US OSHA guide­lines was more impor­tant than har­mon­is­ing inter­na­tion­al­ly. Today, import of machin­ery from the EU is com­mon, and Cana­di­an export of machin­ery around the world is part of doing busi­ness. CSA’s Safe­ty of Machin­ery Tech­ni­cal Com­mit­tee decid­ed to help man­u­fac­tur­ers and importers by har­mon­is­ing Canada’s stan­dards with the Inter­na­tion­al Stan­dards by adopt­ing ISO 13857 as a Cana­di­an Stan­dard.

Fixing the Problem

While the CSA Z432 com­mit­tee was work­ing on revis­ing the stan­dard in 2014/15 it was rec­og­nized that Annex C had caused a lot of con­fu­sion. The com­mit­tee also rec­og­nized that there was no evi­dence that Table 3 or ISO 13857’s tables lead to “less safe” or “safer” machine designs. Since Table 3 didn’t deal with any­thing except open­ings in guard­ing, there was a big gap if Annex C was com­plete­ly dis­card­ed. Users need­ed infor­ma­tion on reach­ing over guard­ing, and on reach­ing through guard­ing where the open­ing was big enough to get an arm through up to the shoul­der, but there were oth­er obstruc­tions inside that might lim­it access to haz­ards. This infor­ma­tion was avail­able in ISO 13857. The deci­sion was tak­en by the com­mit­tee to adopt ISO 13857:2008 as a Cana­di­an stan­dard, and so it became CA/CSA-ISO 13857–2015.

When CSA Z432-16 was issued in Octo­ber of 2016, the nor­ma­tive text includ­ed both stan­dards. The old Table 3 has been cor­rect­ed (the SI con­ver­sions in the 2004 edi­tion were…off) and incor­po­rat­ed as Table 10.1, and the text allows that CAN/CSA-ISO 13857 can be used instead.

The Bottom Line

Cana­di­an machine builders can now use EITHER CSA Z432-16, Table 10.1, OR ISO 13857’s tables. They both result in safe designs. The big dif­fer­ence is that Table 10.1 will often result in a some­what more com­pact machine, BUT, ISO 13857 has fin­er gra­da­tions in the reach-through tables, and also allows for users old­er than 14 or younger than 14, so may be more advan­ta­geous depend­ing on the end-use envi­ron­ment and the spe­cif­ic design issues you are required to con­sid­er.

One final point: ISO 13857 is under review, with a new edi­tion expect­ed in 2017. Pro Tip: The basic tables remain unchanged, and there is lots of new infor­ma­tion in the com­ing update.

Public Review

If you are inter­est­ed in review­ing and com­ment­ing on this adop­tion, please vis­it the CSA Pub­lic Review Page for the stan­dard. Com­ments close 13/07/2015.


Iden­ti­fi­er: Z13857

Title: Safe­ty of machin­ery — Safe­ty dis­tances to pre­vent haz­ard zones being reached by upper and low­er limbs (Adop­tion with­out devi­a­tions) (New Stan­dard) Expiry date: 13/07/2015

This Inter­na­tion­al Stan­dard estab­lish­es val­ues for safe­ty dis­tances in both indus­tri­al and non-indus­tri­al envi­ron­ments to pre­vent machin­ery haz­ard zones being reached. The safe­ty dis­tances are appro­pri­ate for pro­tec­tive struc­tures. It also gives infor­ma­tion about dis­tances to impede free access by the low­er limbs (see 4.3).

ed. note: This post was cor­rect­ed and updat­ed 28-Aug-2017.